Yamaha Srv540 Snowmobile Service Manual Repair 1981-1991 Srv 540 – PDF Download

1981 SR540E

SECTION INDEX GENERAL ENGINE CARBURETION POWER TRAIN CHASSIS ELECTRICAL APPENDIX RACING TIPS

1981 SR540E

CHAPTER 1. GENERAL 1-1.

EXTERNAL VIEW .......................................................................................................... 1-2

1-2.

MACHINE IDENTIFiCATION ...................................................................................... 1-3

A. B. 1-3.

1-4.

Frame serial number ............................................................................................ 1-3 Engine serial number ........................................................................................... 1-3

MAINTENANCE INTERVALS CHARTS .................................................................... 1-4 A.

Periodic maintenance .......................................................................................... 1-4

B.

Lubrication intervals ............................................................................................ 1-5

HIGH ALTITUDE TUNING .......................................................................................... 1-5

1981 SR540E

CHAPTER 1. GENERAL 1-1. EXTERNAL VIEW

1-2

1981 SR540E

1-2. MACHINE IDENTIFICATION A. Frame serial number The frame serial number is located on the righthand side of frame (just below the front of seat). The first three digits identify the model. This is followed by a dash. The remaining digits identify the production number of the unit.

Frame starting serial number

B. Engine serial number The engine serial number is located on the fan case. The prefix indicates engine type and displacement. The prefix is followed by a dash and the serial number. Normally both frame and engine serial numbers are identical.

8L9-016101

Engine starting serial number

SA535-016101

1-3. MAINTENANCE INTERVALS CHARTS A. Periodic maintenance (Use this just as guide only. Certain conditions may require more frequent inspection of components.)

Every Check point

20 hrs. or 400km (250mi)

40 hrs. or 800km (500mi)

80 hrs. or 1.600km (1.000mi)

When necessary

Seasonally

ENGINE: Tightness of bolts and nuts

0

0

Bends. cracks and wear

0

0

Abnormal noise

0

0

Loose connection and breaks of fuel and pulse pipes

0

0

Loose connection and breaks of oil pipes

0

0

Loose connection and breaks of oil delivery pipe

0

0

Fan belt tension/cracks/damage

0

Manual rope starter system

0 0

0

Carburetor •

Operation of starter jet

•

Mixing adjuster (pilot screw)

•

Idling speed adjustment

0

0

..

Operation and adjustment of oil pump

,,_.

0

0

0

0 0

0

0

Ignition timing Cylinder compressions

0

0 0

Cylinder head/exhaust pipe decarbonize Spark plug condition. gap and cleaning

0

Tightening of the cylinder head••

0 0

1-3

1981 SR540E

Every Check point

20 hrs. or 400km (250mi)

40 hrs. or 800km (500mi)

80 hrs. or 1.600 km (1.000mi)

When necessary

Seasonally

DRIVE: Tightness of bolts and nuts

0

Wear on slide runners

0

Primary drive system

0 0 0

V-belt

0

0 0

Secondary drive system

0

0

Sheave distance

0

0

Sheave offset

0

0

8rake pad wear

0

0

Brake operation and adjustment

0

0

Guide wheel rubber

0

0

Wear of drive track wheel sprocket

0

0

Drive track adjustment

0

0

Breaks in drive track

0

0

Bends in front and rear axles

0

0

Checking of lock washers

0

0

Drive chain adjustment

0

0

Drive chain oil level '

0

0

CHASSIS: Tightness of bolts and nuts

0

0

Bends and cracks

0

0

Welded riveted. joints

0

Ski adjustment Ski runner wear

0 0

0

0

0

0

Breaks in fuel tank

0

Cleaning of fuel tank

0

Fuel filter

0

Loose connection and breaks in fuel pipe

0

Breaks in oil tank

0

Oil filter

0 0 0

ELECTRICAL: Wear. breakage of wire covering

0

Breaks in high-tension cord

0

0 0

Voltage regulator working voltage

0

Operation of engine stop switch

0

0

Operation of tether switch

0

0

Headlight

0

0

Taillight

0

0

Brake light

0

0

•• Retighten every 10 hours from the first use.

1-4

1981 SR540E

B. Lubrication intervals Every Check point

20 hrs. or 400km (250mi)

40 hrs. or 800km (500 mil

80 hrs. or 1.600km (1.000 mil

When necessary

Oil/Grease Brand name

. Seasonally

ENGINE:

0

Starter case Oil pump contr~1 box

0

0

Pump drive cover

0

0

Oil in the oil tank

Aeroshell grease #7 A or Esso Beacon 325 grease YAMAlUBE 2-cycle oil

0

DRIVE: Primary sheave weight and roller pins

0

0

Secondary shaft and Sliding sheave

0

0

Front axle housing

0

0

Shaft 1 and shaft 2 (Slide rail) Drive chain oil replacement

0

0

Molybdenum disulfide snowmobile grease

light all-purpose grease

0

0

Gear oil API "Gl-3" SAE #75 or #80

Steering column lower bearing

0

0

light all-purpose grease

Steering column upper bearing

0

0

Motor oil

BODY:

Steering links

0

0

Ski column

0

0

Ski retaining pin

0

0

light all-purpose grease

Brake cable end stopper and brake lever

0

0

Esso Beacon 325 grease

r>

Telescopic strut suspension

1-5

light all-purpose grease

1981 SR540E

1-4. HIGH ALTITUDE TUNING To attain the best machine performance to match high altitude condition. the snowmobile must be properly set.

The tuning should be done as follows.

Confirm STD settings .Carburetor (Page 3·21 .Ignition timing (Page 6-31 • Spark plug (Page 6-61

1 Adjust main Jet size according to the chart (Page 3-41

J Test main jet size (performance & plug colour!

Not OK

Adjust main jet size

(Page 3-3)

I

I

~

I

OK

~

L-____!Te_s_t_lo_w_s_p_e_e_d_s_et_ti_n_g__

Not OK

,-~~I··--------~~ ______________-J~K I

Not OK

OK Check to see if gearing is too high or low

Try high altitude settings Not OK

OK Not OK

•

OK

Adjust gearing as reqUired (Page 4-131

I

I

Decide if problem is slow jet

Not OK

OK

and adjust accordingly

Check engagement speed and Not OK

OK

shift performance

High altitude Not OK

OK

Adjust primary clutch as required (Page 4-4)

Not OK

OK

Adjust secondary clutch as required Not OK

(Page 4-91

'-6

OK

tUning O. K.

1981 SR540E

CHAPTER 2. ENGINE 2-1.

2-2.

DiSASSEMBLy .............................................................................................................2-2 A.

Engine removal .....................................................................................................2-2

B.

Starter .....................................................................................................................2-2

C.

Cooling fan ............................................................................................................2-3

D.

Flywheel magneto ................................................................................................2-3

E.

Oil pump ................................................................................................................2-4

F.

Engine disassembly .............................................................................................2-5

INSPECTION, REASSEMBLY AND ADJUSTMENT .............................................. 2-6

A.

Engine component ...............................................................................................2-6

B.

Oil pump ..............................................................................................................2-12

C.

Flywheel magneto .............................................................................................2-14

D.

Cooling fan .......................................................................................................... 2-15

E.

Starter. ................................................................................................................. 2-18

F..

Engine remounting ............................................................................................ 2-19

1981 SR540E

CHAPTER 2. ·ENGINE 2-1. DISASSEMBLY A. Engine removal Remove the engine by removing the following parts.

Engine mounting nuts

NOTE:----------------------~

Engine

It is not necessary to remove the engine to remove the following parts: • Cylinder head • Cylinder • Piston • Autolube pump • Manual starter assembly • Cooling fan • Flywheel magneto • Carburetor • Intake reed valve

B. Starter 1. Remove starter assembly from the fan case .

Snowmobile

V-belt

2. Remove the drive plate mounting nut at its center, and remove the drive plate.

Primary sheave (Refer to "4-1- B. Primary-sheave")

Carburetor (Refer to "3-1-B. Carburetor Overhauling)

Muffler Fuel pipe Oil pipe

3. There is a drive plate spring and a drive pawl under the drive plate.

Pulse pipe Tachometer cable

NOTE:------------------------~

Magneto lead wire

Take care so that they are not lost.

Manual starter handle Shroud stopper

2-2

1981 SR540E

1. Rotor holding tool

1. Drive plate spring 2. Drive pawl 3. Return spring

3. Remove the drive fan pulley and fan belt.

4. Remove the sheave drum.

CAUTION: - - - - - - - - - - - .

There is a starter spring (coiled) under the sheave drum. Care should be taken so that it will not spring out.

5. To remove the starter rope. undo the knot on one end of the rope. Then pull it out from the starter case.

C. Cooling fan 1. Remove the fan case cap.

4. Remove the fan case assembly.

2. Using the rotor holding tool. remove the three bolts. and remove the starter pulley.

Tool name

Tool No.

Rotor holding tool

90890-01235

5. Remove the driven fan pulley securing nut. spring washer. plate washer. fan pulley. key. and washers (shims).

NOTE:------------------------Take care so that the key and washers (shims) are not lost.

2-3

1981 SR540E

No.

Tool name

Tool No.

1

Drive handle

90890-01817

2

Flywheel puller bolt

90890-01803

3

Flywheel puller body

90890-01848

4

Flywheel puller screw (4)8 X 80 mm)

90890-01806

5

Flywheel puller attachment

90890-01804

6. Remove the cooling fan assembly by tapping the fan shaft.

NOTE:------------------------When removing the flywheel. the key must be removed from the crankshaft.

Take care so that it is not lost.

3. Remove Phillips-head screw. and remove the coil plate.

D. Flywheel magneto 1. Using the rotor holder tool. remove the flywheel mounting nut.

Tool name

Tool No.

Rotor holding tool

90890-01235

E. Oil pump 1. Remove the oil delivery pipes.

2. Remove the bolts and pump drive case.

1. Rotor holding tool

NOTE:------------------------The oil pump can be removed as an assemb~ Iy together with the pump drive cover. If it is hard to remove the pump drive case. tap it with a soft-faced hammer.

2. Using the flywheel puller. remove the flywheel assembly.

2-4

1981 SR540E

3. Remove the exhaust pipe assembly.

4. Remove the cylinder head holding nuts. cylinder head and gasket.

CAUTION:------------------~

The oil pump must not be disassembled, because the oil pump is a precision NOTE:--------------------------

work.

Loosen spark plugs before removing cylinder head.

3. Remove oil pump cap and pump wire.

4. Remove oil pump assembly.

5. Remove the cylinder holding nuts. cylinder and cylinder base gasket.

6. Remove piston pin clip from piston.

F. Engine disassembly 1. Remove the air shroud.

2. Remove the intake manifold and reed valves.

NOTE:-----------------------Before removing the piston pin clip. cover the crankcase with a clean rag to prevent the clip from accidentally falling into the crankcase.

7. Push piston pin. from opposite side. then pull out. Protect pin with rag.

NOTE:-------------------------Before moving piston pin. deburr clip groove and pin hole area.

8. Remove engine brackets.

9. Remove crankcase holding bolts. Each bolt position is numbered. Start with the largest number for disassembly. Loosen each bolt 1/4 turns and proceed to the next.

NOTE:------------------_______ For reed valve inspection. refer to 3-2 Reed valve.

2-5

1981 SR540E

10. Split crankcase by lightly striking the upper and lower crankcases.

11. Remove crankshaft by tapping the shaft with your hands.

CAUTION: - - - - - - - - - . . . . . , When removing pump drive gear, replace it with new one.

2-2. INSPECTION, REASSEMBLY AND ADJUSTMENT A. Engine components 1. Crankcase a. Thoroughly wash the case halves in mild solvent. b. Clean gasket matching surfaces and crankcase matching surfaces thoroughly. c. Visually inspect case halves for any cracks, road damage, etc. d. Check oil delivery passages in transfer. ports for signs of blockage.

2. Bearing and oil seal inspection a. After cleaning and lubricating bearings, rotate outer race with a finger. If rough spots are noticed, replace the bearing.

b. Install bearing(s) with . their manufacturer's marks or numbers facing outward. (In other words, the stamped letters must be on the. exposed to view side.) c. Install oil seal(s) with their manufacturer's marks or numbers facing outward. d. When installing bearing(s) or oil seal(s). apply the specified lUbrication.

Crank bearing Crankshaft oil seal lip

Yamalube 2-cycle oil Low temperature grease (Esso Beacon 325 or Aeroshell grease #7 Al

4. Crankshaft inspection a. Check connection rod axial play at small end. (to determine the amount of wear of crank pin and bearing at big end).

If small end play exceeds tolerance, disassemble the crankshaft, check connecting rod, crank pin and big end bearing.

Replace defective parts. Play after reassembly should be within specification.

b. Check oil seal lips for damage and wear.

Replace as required.

Road axial play: Maximum 2.0 mm (0.079 in)

3. Bearing and oil seal installation a. When installing or removisng left crank oil seal and bearing, remove the pump drive gear and install the new drive gear.

2-6

1981 SR540E

b. Check the connecting rod side clearance at big end.

If axial play exceeds tolerance. disassemble the crankshaft and replace any worn parts. Big end axial play should be within specification.

5. Crankshaft installation a. Install the circlip half on crank bearing as illustrated. (The primary sheave side.)

LOWER CASE

Rod side clearance Minimum

Maximum

0.25 iTlm (0.010 in)

0.75 mm (0.030 in)

UPPER CASE

.1. Circlip

2. Sealing surface

3. Knock-pin

b. Install the crankshaft assembly with oil seal. align the bearing punch marks with the crankcase lower and upper matching surfaces.

c. Check crankshaft assembly runout (misalignmentof crankshaft parts).

Dial gauge readings should be within specification.

Correct any misalignment by tapping the flywheel with a brass hammer and/or by using a wedge.

Deflection tolerance Left side

Center (left)

Center (right)

Right side

0.03 mm (0.0012 in)

0.04mm (0.0016 in)

0.04mm (0.0016 in)

0.05mm (0.0020 in)

c. Set the pins of bearing and labyrinth .seal in pin holes of crankcase upper by moving the bearings and labyrinth seal.

2-7

1981 SR540E

FWD

<=

c. After reassembly. apply a liberal coating of two-stroke oil to the crank pin. bearing and into each crankshaft bearing oil delivery hole.

3. Upper case 4. Aligning mark

1. Knock pin 2. Sealing surface

CAUTION:------------------~

The oil seal lip must fit crankcase groove.

into the

d. Check crankshaft for freedom of movement.

7. Engine bracket installation Install the engine brackets in the correct position.

6. Crankcase installation a. Apply YAMAHA BON D #4 to the mating surfaces of both case halves.

Apply thoroughly over all matching surfaces. b. Set the crankcase half onto lower case half. Install the crankcase holding bolts.

Each bolt position is numbered. Tighten all crankcase holding bolts gradually in the order of the numbers marked on crankcase.

Tightening torque 8 mm Bolt 6 mm Bolt (No.ll )

First

1.0 m-kg (7 ft-Ib)

Final

2.0 m-kg (15 ft-Ib)

First

0.5 m-kg (3.5 ft-Ib)

Final

1.0 m-kg (7 ft-Ib)

Tightening torque: 2.0 m-kg (14.5 ft-Ib) 8. Piston pin and bearing inspection a. Check the pin for signs of wear. If any wear is evident. replace pin and bearing.

2-8

1981 SR540E

b. Check the pin and bearing for signs of heat discoloration. If excessive (indentation on pin. etc.). replace pin and bearing. c. Check the bearing cage for excessive wear or damage. Check the rollers for signs of flat spots. If such wea~ is found. replace pin and bearing. '

9. Piston inspection a. Remove piston rings. b. Remove carbon deposits from piston crown.

c. Carefully remove carbon deposits from ring grooves with filed end of ring. d. Remove score marks and lacquer deposits from sides of piston using 600 800 grit wet sandpaper. Sand in a crisscross pattern. Do not sand excessively.

~ ,,~, ,

!"'oJ

d. Apply a light film of oil to pin and bearing surfaces. Install them in connecting rod small end to inspect for wear. Check for play. There should be no noticeable vertical play. If play exists. check connecting rod small end for wear. Replace pin. connecting rod and/or bearing. as required.

e. The piston pin should have no noticeable free play in the piston. If the piston pin is loose. replace the pin and/or piston.

2-9

1981 SR540E

e. Wash piston in solvent and wipe dry. f. Measure the outside diameter of the piston at the piston skirt.

Measurement should be made at a point 17 mm (0.67 in) above the bottom edge of the piston. Place the micrometer at right angles to the piston pin.

Piston maximum diameter subtracted from minimum cylinder diameter gives piston clearance. If beyond tolerance. hone cylinder to tolerance or bore to next oversize and fit oversize piston.

b. Measure ring end gap in free position. If beyond tolerance. replace ring set.

Ring end cap. free Approx. 8 mm (0.31 in)

c. Push the ring into the bore and check end gap clearance with a feeler gauge.

If beyond tolerance. replace ring set.

Ring end gap. installed Minimum ............. 0.30 mm (0.012 in) Maximum ............ 0.50 mm (0.020 in) 1. 17 mm (0.67 in)

Piston clearance: Minimum ........ 0.055 mm (0.0022 in) Maximum ....... 0.060 mm (0.0024 in) Piston oversize: 73.25 mm (2.884 in) 73.50 mm (2.894 in) 73.75 mm (2.904 in) 74.00 mm (2.913 in) 10. Piston ring inspection a. Check rings for scoring any severe scratches and noticed. replace ring set.

11. Piston installation a. Install the piston rings as illustrated.

<D /11111/11111(5111111111111

________'l~ ~______~ '11111111111JJ1177777171JI @

1. Piston head

2. Piston bottom

3. Piston ring

2¡10

1981 SR540E

b. During reassembly. coat the piston ring grooves. piston skirt areas. piston pin. and bearing with two-stroke engine oil. c. Install new piston pin clips and make sure they are full-seated in their grooves.

NOTE:------------------------Take care during installation to avoid damaging the piston skirts against the crankcase as the cylinder is installed. Be sure the arrow stamped on the piston crown points forward.

2

.........

~ ......

--------~ ---------- .....

3

------

Cylinder bore

12. Cylinder inspection a. Inspect the cylinder walls for scratches.

If vertical scratches are evident. the cylinder wall should be rebored or the cylinder should be replaced.

NOTE:--------------------------

Standard

Wear limit

73.00~ 73.02 mm (2.874~2.875 in)

73.05 mm (2.876 in)

Cylinder taper

-

0.05 mm (0.002 in)

Cylinder out-of-round

-

0.01 mm (0.004 in)

If the cylinder wall is worn more than wear limit. it should be rebored.

Cylinder size mark is stamped upper part of the intake port.

13. Cylinder installatior a. Install a new cylinder base gasket. b. Install cylinder with one hand while compressing piston rings with other hand.

NOTE:-----------------------Make sure the rings are properly positioned.

b. Measure cylinder wall wear as shown. If wear is excessive. compression pressure will decrease. Rebore the cylinder wall and replace the piston and piston Cylinder wear should be rings. measured at three depths with a cylinder bore gauge. (See illustration) 2-11

1981 SR540E

c. Working in a crisscross pattern, tighten the cylinder nuts in two steps.

Cylinder holding nut torque: 2.5 m-kg (18 ft-Ib)

14. Cylinder head inspection a. Remove spark plug. b. Using a rounded scraper, remove carbon deposits from combustion chamber. Take care to avoid damaging spark plug threads. Do not use a sharp instrument. Avoid scratching the aluminum.

c. Install the manifold.

reed

valve

and

intake

Tightening torque: 1 .0 m-kg (7 ft-Ib)

NOTE:-----------------------For reed valve inspection, see "3-2. REED VALVE"

17. Exhaust pipe installation Remove the carbon deposits from exhaust pipe. Inspect the exhaust gasket for damage and replace it as required.

Install the exhaust pipe with gasket.

15. Cylinder head installation Install cylinder head gasket and cylinder head. Working in a crisscross pattern, tighten head nuts in two steps.

Tightening torque: 2.3 m-kg (16.5 ft-Ib)

Head nut torque: 2.5 m-kg (18 ft-Ib)

18. Install air shroud.

Tightening torque: 0.6 m-kg (4 ft-Ib)

16. Intake manifold installation a. Clean the mating surfaces of cylinder, reed valve and intake manifold. b. Coat the mating surfaces of cylinder, reed valve and intake manifold with Three Bond #50 and install new intake manifold gaskets.

B. Oil pump 1. Minimum pump stroke checking and adjustment.

Normally the checking the adjustment of the pump stroke are not required, but if any sign of trouble resulting from an incorrect minimum pump stroke is noticed (e.g., excessive engine oil consumption or engine s~izure). proceed as follows: 2¡12

1981 SR540E

a. Remove the oil pump assembly from the engine. b. Turn the oil pump worm wheel until the pump plunger moves fully out and away from the pump body to its outermost limit. c. Measure the gap with the thickness gauge between the raised boss on the pump adjust pulley and the adjust plate.

1. Adjust shim

f. Reinstall adjust plate and lock nut.

Tighten the lock nut. Re-measure gap.

Repeat procedure as required.

2. Oil pump drive case installation Coat the pump drive gear with grease.

And install the pump drive case.

Recommended grease: Low temperature grease (Esso Beacon 325 or Aeroshell grease #7A) Pump case tightening torque: 1 .0 m-kg (7 ft-Ib)

3. Install pump wire, pump case and oil delivery pipe.

CAUTION: - - - - - - - - - . . . , Before installing pump wire and pump case, apply grease to the pump pulley thoroughly.

1. Adjust plate 2. Adjust pulley 3. ~inimum pump stroke

Minimum pump stroke: 0.20,...... 0.25 mm . (0.0079,...... 0.0098 in)

Recommended grease: Low temperature grease (Esso Beacon 325 or Aeroshell grease #7A)

d. If clearance is not correct, remove the adjust plate lock nut and the adjust plate. e. Remove or add an adjust shim as required.

4. Air bleeding (After remounting engine) The oil pump and delivery lines must be bled on the following occasions: â&#x20AC;˘ Setting up a new machine out of the crate. â&#x20AC;˘ Whenever the oil tank has run dry. â&#x20AC;˘ Whenever any portion of the oil pump system is disconnected.

2-13

1981 SR540E

3) Keep the engine running at about 2,000 r/min for two minutes or so, and both distributor and delivery pipe can be completely bled.

5. Cable adjustment (After remounting engine) a. Adjust throttle cable free play.

(See 3-1-A. Carburetor tuning) b. Pull the oil pump cable outer tube toward the oil pump and adjust the gap between the adjuster and the outer tube to specification,

a. Bleeding the pump case and/or oil pipe.

1) Remove the oil pump bleed screw.

1. Bleed screw

Play: 25

2) Keep the oil runnin,g out until air bubbles disappear.

3) When air bubbles are expelled completely, tighten the bleed screw.

± 1 mm (0.98 ± 0.04 in)

c. After adjusting, don't forget to tighten the lock nut.

NOTE:----------------------Check the bleed screw gasket, and if damaged, replace with a new one. b. Bleeding the pump distributor and/or delivery pipe.

1) Start the engine.

2) Pull the pump wire all the way out to set the pump stroke to a maximum.

1. Play

2. Adjuster 3. Lock nut

C. Flywheel magneto (For inspection, refer to "6-1-G. Pulser and charge coil test" and "6-2-C. Lighting circuit test",) Inspection Check the flywheel magneto for any looseness, If it is loose, retighten to the following torque and apply an adhesive,

1. Pull 2. Pump wire

NOTE:------------------------

Tightening torque: Weight ring and ring gear stay: 1,0 m-kg (7,2 ft-Ib) Flywheel magneto and ring gear stay: 1.5 m-kg (10.8 ft-Ib)

It is difficult to bleed the distributor completely with the pump stroke at a minimum, and therefore the pump stroke should be set to a maximum.

2·14

1981 SR540E

D. Cooling fan 1. Inspection a. Check the fan shaft bearings for damage. If damaged, replace. b. Check the cooling fan for damage. If damaged. replace. c. Check the fan belt for damage and wear. If worn excessively. replace.

2. Installation a. Install the cooling fan assembly and fan driven pulley assembly.

Tightening torque: 1.5 m-kg (1 O.S ft-Ib) Tightening torque: 1.0 m-kg (7.2 ft-Ib)

Driven fan pulley securing nut torque: 4.3 m-kg (31.1 ft-Ib)

@:

LOCKTITEÂŽ LOCK "n" SEAL (adhesive)

1. Weighr ring 2. Ring gear stay 3. Spring washer

4. Hexagon socket head bolt 5. Solt 6. Spring washer

1. Install woodruff key.

2. Install flywheel base.

Flywheel base tightening torque: 0.65 m-kg (5 ft-Ib)

NOTE:------------------------For shim installation. see fan tension adjustment of next section.

3. Install flywheel using sheave holder.

Too name

Tool No:

Sheave holder

90890-01701

b. Install the fan case assembly.

NOTE:--------------------------

Tightening torque: 2.3 m-kg (16.5 ft-Ib)

Make sure woodruff key is properly seated in keyway of crankshaft. Carefully install flywheel while taking care so it aligns with woodruff key.

c. Install the fan drive pulley with fan bent.

Flywheel nut torque: 7.3 m-kg (53 ft-Ib)

4. Adjust ignition timing.

CAUTION:------------------~

Whenever the flywheel magneto is removed, ignition timing must be reset.

(Refer to 6-1-C. Ignition timing) 2-15

1981 SR540E

d. Install the starter pulley.

Tightening torque: 2.3 m-kg (16.5 ft-Ib) e. Install the fan case cap.

Fan Case Assembly Ref. No.

Description

a'ty

Remarks

Fan case 2 Tightening torque: 4.3 m-kg (31 ft-Ib) 14 11 9 10

7

8 7 12

Bearing (B6203)

3

Circlip

4

Plate washer

5

Fan

6

Woodruff key

2

7

Pulley 2

2

8

Claw washer

1 UR

1

9

Spring washer

10

Plain washer

11

Nut

12

Belt Pulley 1 Fan case cover

5 Tightening torque: 4.3 m-kg (31 ft-Ib)

7 11

2

5 Tightening torque: 2.3 m·kg (16.6 ft-Ib)

++ 2·16

1981 SR540E

NOTE:--------------------------

3. Fan belt tension adjustment The fan belt tension should be checked by pushing the belt 8 mm (0.31 in) at its center.

If the tension is less than the specified value. adjust the¡ fan belt.

Take care so that adjusting washers are not lost. d. First. install the fan driven pulley.

Next. install the fan drive pulley with fan belt.

Fan belt tension: New belt (preset tension) 6.5 f""'oJ 8.5 kg/8 mm (14.3 f""'oJ 18.7 Ib/0.31 in) Normal 4f""'oJ 6 kg/8 mm (8.8 f""'oJ 13.2 Ib/0.31 in)

Tightening torque Fan driven puiiey

4.3 m-kg (31.1 ft-Ib)

Fan drive pulley

2.3 m-kg (16.5 ft-Ib)

CAUTION: - - - - - - - - - - , Before tightening fan driven pulley securing nut, do not install fan belt. e. Check the fan belt tension If the tension is not correct. readjust the belt tension by repeating the procedures a. from d. above. until tension is correct. f. After adjusting fan belt tension correctly tighten the fan driven pulley. securing nut. spring washer and plain washer.

a. Remove the fan drive pulley and the fan belt. b. Remove the fan driven pulley. c. Remove or add adjusting washers as required.

Washer q'ty

Decrease

Belt tension

Increase

---

Increase Decrease

Washer parts No.

Thickness

90214-17017

0.5 mm (0.02 in)

90214-17018

1.0 mm (0.04 in)

1. Fan shaft 2. Plain washer

2-17

3. Spring washer 4. Nut

1981 SR540E

E. Starter

handle and release it. making sure that the starter handle returns to the housing rope eye.

1. Install the starter spring in the starter case.

NOTE:------------------------

4. Place the drive pawl. return spring. drive plate spring. drive plate and tighten the thrust washer and nut.

1. It is necessary to wind the spring to a small size before installing it in the starter case.

2. Be careful' not to install the spring in a wrong way.

3. Hook the loop on the outer end of the spring onto the spring hook in the star. ter case. Then thoroughly grease the spring.

NOTE:------------------------Grease the pivot of the drive pawl.

Tightening torque: 1.0 m-kg (7 ft-Ib)

2. Wind the starter rope around the sheave drum. and put it into the starter case.

Hook the knot on the rope end onto the cut in the sheave drum (as illustrated). and wind the rope around the sheave drum in the direction of the arrow. leaving about 370 mm (14.6 in).

The other end of the rope is connected to the starter handle.

5. After the completion of assembly. check the starter for smooth operation.

Pull out the starter rope about 80 130 mm (3 5 in). and make sure that the starter pawl moves out of the drive plate. roo.J

roo.J

370mm

1. Drove plate spring 2. Drive pawl 3. Return spring

3. Bring the rope end out of the cut in the sheave drum. and turn the sheave drum 4 turns counterclockwise to give the starter spring preload. Pull the starter

2-18

1981

SR540~

6. Install the starter assembly on the fan case.

Tightening torque 0.7 m-kg (5.0 ft-Ib)

F. Engine remounting Install the engine as follows: Engine

NOTE:-------------------------

Engine mounting nuts

Refer to .. 4-1-A. Sheave adjustment".

CAUTION: - - - - - - - - - - . . .

Take care not to pinch the wire and pipes between the engine and frame.

Manual starter handle Magneto lead wire Tachometer cable

NOTE:--------------------------

Carburetor

For adjusting. see "3-1, Carburetor", For routing. see CABLE ROUTING DIAGRAM. WARNING:------------~

By turning out the throttle lever 2 or 3 turns, make sure it operates correctly.

2-19

1981 SR540E

~

CAUTION: - - - - - - - - - - ,

Pulse pipe

The oil pipe, in which the oil filter is installed, must be correctly connected to the oil pump.

Fuel pipe Oil pipe

NOTE:-----------------------After installing oil pipe, the autolube system must be bled. (Refer to 2-2-8-4. Air bleeding)

Muffler

NOTE:------------------------

Primary sheave

Refer to "4-1-8. Primary sheave".

NOTE:~---------------------­

V-belt

For inspection, see "4-1-C. V-belt".

Snowmobile

2-20

1981 SR540E

CHAPTER 3. CARBURETION 3-1.

CARBURETOR ..............................................................................................................3-2

A.

Carburetor tuning .................................................................................................3-2

B.

Overhauling ...........................................................................................................3-5

C.

Troubleshooting .................................................................................................3-10

3-2.

REED VALVE ...............................................................................................................3-12

3-3.

FUEL PUMP ................................................................................................................3-12

3-4.

SI LENCER JOINT .......................................................................................................3-13

CHAPTER 3. CARBURETION 3-1. CARBURETOR

If free play is not correct. loosen the throttle cable securing screw and adjust throttle cable. After adjusting. be sure to tighten the screw prO.l?erly.

A. Carburetor tuning 1. Standard specification The carburetor is set at the factory to run at temperatures of O째C to -20째C (32 째 F to - 4 째 F) at sea level. If the machine has to be operated under conditions other than specified above. the carburetor must be reset as required.

Special care should be taken in carburetor setting so that pistons will not be holder or seized.

Main jet

#150

Power jet

#150

Slow jet

#92

Pilot screw

2-1/4 turns out

Starter jet

#160

Throttle cable securing screw tightening torque: 0.4 m-kg (3.0 ft-Ib)

15 +2 mm Float height Idling engine speed

-3+ 0 .079

(0.59 -0.118 in) 1.500 r/min

CAUTION: - - - - - - - - - - - .

If the air silencer box is removed from the carburetors, the change in intake pressure will create a LEAN MIXTURE that may result in severe engine damage. The air silence box has no effect on performance characteristics and it must be secured to the carburetor during carb tuning and adjustment. It must always be in place when the engine is operated. Examine the silencer regularly for cleanliness and freedom from obstruction.

1. Screw

WARNING: - - - - - - - - - - - , Throttle cable must not be lubricated in any way. It must be routed correctly to avoid throttle problems that may lead to an unsafe condition during operation.

2. Carburetor cable adjustment a. Throttle cable adjustment Check throttle cable free playas specified when throttle closed (idling throttle).

b. Starter cable adjustment Pull the starter cable outer tube upward. and adjust the free play between the outer tube end and adjuster to specification by turning the adjuster. After the adjustment. tighten the lock nut and replace the rubber cap to keep the lock nut free from dust and water.

Free play: 1.0'" 2.0 mm (0.04", 0.08 in)

3-2

1981 SR540E

NOTE:-----------------------Starter cable free play must be adjusted after the cable is correctly rounted. (Refer to wire routing diagram.)

Lock nut tightening torque: 0.08 m-kg (0.6 ft-Ib)

1. Pilot screw

b. Start the engine by pulling the starter lever. and fully warm up the engine. c. Set the throttle stop screw so that the engine idles at the specified speed.

0.5 -

1.5 mm (0.02 -

Idling engine speed: 1.500 r/min

0.06 in)

1. Adjuster 2. Lock nut

Free play between outer tube end and adjuster: 0.5,...., 1.5 mm (0.02,...., 0.06 in)

c. Oil pump cable adjustment Refer to "2-2-8-5. Pump cable adjustment".

3. Low speed tuning The carburetor is built so that low speed tuning can be done by adjusting the throttle stop screw and pilot screw.

1. Throttle stop screw

NOTE:-----------------------If the engine shows poor performance in elevation or in an extremely cold area or when it is suddenly accelerated or run at low speeds. proceed as follows: 1. Turn the pilot screw in and out 1/4 turn or less each time. and set it in a position where the engine idles faster.

2. Follow step C" in the preceding paragraph.

CAUTION:------------------~

Always install air silencer before making tuning adjustment. High performance tuning cannot be done without the silencer. Engine damage may result from attempting to tune without the silencer installed.

4. Main circuit tuning No adjustment is normally required. but adjustment is sometimes necessary depending on tempeatures and/or altitude. (Refer to Main jet setting chart.)

a. Tighten the pilot screw lightly. and back it out from its lightly seated position.

Standard pilot screw (turns out): 2-1/4 turns out

3-3

1981 SR540E

[Main jet setting chart]

~

-30°C (-22°F)

Altitude

1--(#155)

600 m (2000 ft)

~

1200 m (4000 ft)

~

1800 m (6000 ft)

-

-10°C (14°F)

I--

#155

t---#150

r--- #145

~

2400 m (8000 ft)

~

3000 m (10000 ft)

r---#140

-#135

- ..

-- ..

--

O°C (32°F)

#150

~

Seal level

~

-20°C (-4°F)

-- -..

#150

#145 #140

--

#135

-

#130

a. Run the engine at high speeds, and make sure the engine operates smoothly. c. Check both spark plugs and, depending on the discoloration of each spark plug, the main jet should be adjusted on the basis of the following table. (Refer to spark plug color samples.)

No. 6

10°C (50°F)

20°C (68°F)

-

---#145#145

#140 #135

#130

• #125

-

..

Bad (Due to lean a mixture, the spark plug melts.)

Check the piston for holes or seizure.

Check the cooling system, gasoline octane rating and ignition timing. After replacing the spark plug with colder type, tune the carburetor again, starting with low-speed tuning.

Standard main jet: #150

Spark plug color No.1

Good (Carburetor is tuned properly.)

No.2

Bad (Mixture is too rich.)

Replace main jet with one-step smaller one.

No.3

Bad (Mixture is too lean.)

Replace main jet with one-step larger one.

No.4

Bad (Due to too lean a mixture, piston is holder or seized.)

Replace the piston and spark plug.

Tune the carburetor again, starting with low-speed tuning.

No. 5

Bad (Due to too lean a mixture, the engine knocks.)

Check the piston for holes or seizure.

Check the cooling system, gasoline octane rating and ignition timing. After replacing the spark plug, tune the carburetor again, starting with low-speed tuning.

1. Main jet

WARNING: - - - - - - - - - - - - , Never remove the main jet cover bolt while the engine is hot. Fuel with flow out of the float chamber which could ignite and cause damage to the snowmobile and possible injury to the mechanic.

Place a rag under the carburetor so fuel does not speed, Place the main jet cover bolt in a clean place. Keep away from fire. After assembling the carburetor, firmly tighten the rubber joint screw.

Make sure the throttle outer tube is in place and the throttle cable moves 3-4

1981 SR540E

smoothly. Clean the carburetor and allow it to dry.

B. Overhauling

1.

2.

3.

4.

5.

6.

7.

B. 9.

10.

11.

12.

13.

14.

15.

16.

17. lB. 19.

20.

21.

22.

23.

24.

25.

26.

27.

2B.

1._14 I=--15

~'6 ~-21 6

18----9

4-

20

19~

1. Disassembly a. Remove the carburetor from the engine. and discor;mect the control cables as follows: 1) Loosen the throttle cable holder screw.

2) Remove the pump cable adjuster from the stay plate. and remove the pump cable from the lever.

3) Remove the cap from the carburetor. together with the starter valve. and disconnect the starter cable.

1. Throttle cable 2. Pump cable 3. Starter cable

3-5

Carburetor ass'y Spring Hose Slow jet Float O-ring Float cha mber body Starter plunger cap cover Cable adjuster Starter plunger .cap Nut Starter plunger spring Starter plunger Valve seat ass'y Clip Float pin Main jet O-ring Drain bolt Pan head screw with Vl(asher Flathead screw Spring Adjust screw Bolt with washer Stay Bolt Pan head screw Spring

1981 SR540E

CAUTION: - - - - - - - - - . . , When removing the starter cable, take care so that the rubber cap, coil spring and starter cable do not fall off or are not lost. Also use special care not to scratch the rubber seat surface. b. Float chamber 1) Remove the four screws. together with the float cha mber.

2) Remove the main jet cover bolt. together with the O-ring.

c. Carburetor body 1) Remove the screw. together with the float. float arm. and fuel valve assembly.

2) Remove the slow jet and main jet.

3) Remove the pilot screw. together with the coil spring.

4) Remove the throttle stop screw, together with the coil spring.

5) Remove the stay plate. together with the bolt.

NOTE:----------------------1. Hook the clip orito the float arm. and remove the fuel valve while taking care not to drop it.

2. The fuel valve plays a very important role. so special care should be taken so that the rubber part of the needle is not scratched.

3-6

3. Use care to keep the plastic parts free from shocks. because they could be damaged easily.

4. Never wash the rubber parts with alcohol or lacquer thinner. Use gasoline.

2. Inspection CAUTION:------------------~

1) Before checking, thoroughly clean all parts in gasoline, and blow the jets, float chamber and fuel passages in the carburetor body with compressed air so the dust and dirt can be removed.

2) When washing the carburetor body and float chamber, be sure to use a soft brush.

3) When decarbonizing the throttle valve and its adjacent area, take special care not to scratch the throttle valve and throttle bore.

4) Never use a hard wire or the like when cleaning jets. It could scratch or deformed jet holes, thus adversely affecting fuel consumption.

5) Use care so that all parts are not deformed.

CAUTION:-------------------, Never attempt to disassemble the following parts.

1) Throttle valve 2) Throttle shaft Reason: 1) The threaded portion of the screw is clinched after the throttle valve is installed to the throttle shaft so that the screw will not come loose.

2) The bypass hole is precisionmachined so that the correct distance can be maintained from the end of the throttle valve. Therefore, if the throttle valve is once disassembled, it is difficult to reproduce the original dimensions, and thus engine performance will be adverselyaffected.

1

Power air jet (Body jet)

2. Power nozzle 3. Pilot screw 4. Main air jet (Body jet) 5. Power jet (Body jet) =~:::

6. Main jet

':::.1

7. Slow jet 8. Starter jet

II " II II II II II II II

9. Slow air jet

II

_ _ _ _ ,...L... _ _ _ _

=================~ II

II ¡11

I

II

I

::

@

CV

II

~===================~

3-7

@

ÂŽ

1981 SR540E

a. Float chamber 1) Check the starter jet and power jet circuit for clogging with dust. If clogged, blow them off with compressed air.

NOTE:-------------------------If the starter jet is clogged, fuel flow will be hindered and hard starting will result.

1. Power jet

3. Slow circuit

2. Main circuit

4. Starter emulsion tube

NOTE:------------------------If this jet is clogged, engine power loss will result at high speed operation.

3) Clean the main circuit. slow circuit and starter emulsion tube, and blow them off with compressed air.

4) Clean the main air jet. slow air jet. starter circuit.' and air vent. and blow them off with compressed air.

1. Starter jet 2. Power jet circuit

2) Blow the float chamber clean of dust and dirt with compressed air. b. Carburetor body 1) Clean the fuel valve seat while taking care not to scratch the seat. and blow it with compressed air. Check the end of the valve needle for damage. If damaged, replace the valve needle. If the valve seat is damaged, the body should be replaced.

1. Main air jet

2. Slow air jet

3. Starter circuit

5) Blow the pilot screw clean of dust and dirt with compressed air.

6) Check the end of pilot screw for carbon.

Check the tapered portion and threaded portion for damage.

CAUTION:------------------~

A scratched seat could result in the overflow of fuel.

2) Check the power jet for clogging. If clogged, blow it with compressed air.

3-8

1981 SR540E

7) Blow the main jet and slow jet clean of dust and dirt with compressed air.

3. Reassembly and adjustment

6) Float level.

(1) Reinstall components, except for

(2) CAUTION: - - - - - - - - - - - - , 1) Wash all parts in clean gasoline be-

fore assembling.

2) Always use new O-rings.

3) Make sure moving parts rotate or slide smoothly.

4) Apply grease to contact surfaces of the throttle shaft.

the float chamber.

Incline the carburetor at 20 "" 30° (so that the end of the float valve does not hang down of float weight). and measure the distance from the mating surface of the float chamber and carburetor to the top of the float using a gauge.

Float level: 15

a. Carburetor body 1) Install the throttle stop screw and coil spring.

Adjustment: See "Low speed tuning."

2) Install the main jet and slow jet.

3) Install the pilot screw and coil spring.

Adjustment: See "Low speed tuning."

_+ 32

mm (0.59

+ 0.079 -0.118

in)

NOTE:-------------------------The float should be just resting on, but not depressing the spring loaded inlet needle.

NOTE:-------------------------The pilot screw must not be tightened excessively.

4) Install the stay plate.

5) Install the clip to the needle valve, and put it into the valve seat. Insert the arm pin into the float. install the float. and secure the arm pin with screw.

1. Float level

NOTE:-------------------------1. Don't forget toinsert the float arm tang into the clip attached to the needle valve.

2. After assembling, take care not to allow dust and dirt to enter.

(3)

(4)

3-9

If the float level is not within the specified range, check the valve seat and needle valve. And replace any damaged part.

If any part is in good condition but float level is not within the specified range, correct float level by bending the float arm tang slightly.

1981 SR540E

~CAUTION:--------------------_

NOTE:-----------------------By turning the throttle lever to the full-open position two or three times, make sure it operates correctly.

After installing the carburetor body, be sure to apply grease to the following parts as an anti-freeze measure: Recommended low temperature grease: ESSO Beacon 325 or Aero Shell #7

3) Make sure the starter lever is fully pushed in, and install the starter cable and spring to the starter valve, and install the valve in the carburetor.

Adjust the starter cable. (See "Starter cable adjustment.")

1) Throttle return spring, throttle shaft collar.

2) Space between carburetor body and throttle shaft (at 2 places).

3) Throttle lock washer, E-clip.

4) Wire holder attached to the throttle valve.

NOTE:-----------------------By pulling the starter lever two or three times after installation of the starter cable, check the operation of the starter valve.

4) Install the fuel pipe to the carburetor.

Next, install the clip firmly.

C. Troubleshooting This troubleshooting guide relates only to the carburetor. Making an adjustment of the carburetor, check the engine and electrical system. If no defect is found, consult this troubleshooting guide.

CAUTION:------------------~

1) When disassembling the carburetor, use care so that parts don't fall off or are not lost. Also don't strike the carburetor with a hard tool. Dust should be blown off with compressed air.

2) When installing the throttle cable, make sure the throttle valve can be fully opened and closed, and make an adjustment.

b. Float chamber 1) Screw the main jet cover bolt (with 0ring) into the float chamber.

2) Install the O-ring to the float chamber, and install it to the carburetor body.

CAUTION:------------------~

Always use a new O-ring for reassembly. c. Install the air bent pipe in place. d. Push the carburetor into the rubber joint. and secure it with the band.

1) Before installing the carburetor on the engine, connect the control cables in the reverse order of disconnection. Keep the starter valve free from dust and dirt during this operation.

2) Insert the end of throttle wire into the hole in the throttle lever, adjust the play of cable, and secure it with screw. (See "Throttle cable adjustment.")

3-10

1981 SR540E

Trouble Hard starting

Checkpoint

Adjustment

Remedy

Insufficient fuel

Add gasoline

Excessive use of starter (Excessively opened choke)

Clean spark plug

Return starter lever to its home position.

Fuel passage is clogged or frozen

Clean

Parts other than carburetor • Clogged fuel tank air vent. clogged fuel filter. or clogged fuel passage Carburetor Clogged or frozen air vent clogged valve If water collects in float chamber• clean (Also check for ice.)

.

Overflow Poor idling (Relative troubles) Poor performance at low speeds Poor acceleration Slow response to throttle Engine tends to stall

· · · ·

Correct

Improper idling speed adjustment Pilot screw adjustment

Adjust idling speed

• Throttle stop screw

Adjust

Damaged pilot screw

Replace pilot screw

Clogged bypass hole

Clean

Clogged or loose slow jet

Clean and retighten

Air leaking into carburetor joint Defective starter valve seat

Retighten band screw Clean or replace

See "Overflow" Tighten pilot screw lightly. and check throttle opening. If incorrect. back it out specification. Start the engine and turn pilot screw in and out 1/4 turn each time. When the engine runs faster. back out throttle stop screw so the engine idles at specified speed.

Tightened to much-Engine speed is higher.

Backed out too much-Engine does no idle.

Remove slow jet. and blow it out with compressed air.

Overflow

Correct

See "Overflow."

Poor performance at mid-range speeds (Relative troubles) Momentary slow response to throttle Poor acceleration

Clogged or loose slow jet

Clean and retighten

Remove slow jet. and blow it out with compressed air.

·

Lean mixtures

Overhaul carburetor

See "Overflow."

Poor performance at normal speeds (Relative troubles) Excess fuel consumption Poor acceleration

Clogged air vent

Clean

Remove the air vent pipe. and clean.

Clogged or loose main jet

Clean and retighten

Remove main jet. and blow it out with compressed air.

Overflow

Check float and float valve and clean

See "Overflow"

Starter valve is left open

Fully close valve

Return starter lever to its home position

·

· ·

Poor performance at high speeds (Relative trouble) Power loss Poor acceler'ltion

· ·

Clogged air vent

Remove and clean

Clogged or loose main jet

Clean and retighten

Clogged power jet

Clean

Clogged fuel pipe

Clean or replace

Dirty fuel tank

Clean fuel tank

Air leaking into fuel line

Check jOint and retighten

Low fuel pump performance

Repair pump or replace

Clogged fuel filter

Replace

Clogged silencer outlet

Check for ice. and remove

3-11

Remove main jet. and clean with compressed air. then install.

1981 SR540E

Trouble Abnormal combustion (Mainly backfire)

Overflow (Relative troubles) Power idleing Poor performance at low. mid-range. and high speeds Excessive fuel consumption Hard starting Power loss Poor acceleration

Check point

Remedy

Adjustment

Lean mixtures

Clean carburetor and adjust

Dirty carburetor

Clean carburetor

Dirty or clogged fuel pipe

Clean or replace fuel pipe

Clogged air vent

Clean

Clogged float valve

Disassemble and clean

Clean while taking care not to scratch valve seat.

Scratched or unevenly worn float valve or valve seat

Clean or replace float valve and valve seat

Valve seat is press-fitted to body.

So body must be replaced if seat is damaged.

Broken float

Replace float

I ncorrect float level

If not within the specified

• Worn float tang

range. check the following parts and replace any defective part Replace float Replace arm pin Replace float

• Worn arm pin Deformed float arm

· 3-2. REED VALVE

Replace float assembly.

5. Check reed valve for beinding. If beyond tolerance. replace reed valve.

1. Remove the reed valve assembly.

(Refer to 2-1-F. Engine disassembly) 2. Inspect rubber carburetor joint for signs

Reed valve beinding limit: 0.6 mm (0.024 in)

of weathering. cracking or other deterioration.

3. Inspect reed petals for signs of fatigue and cracks. Reed petals should fit flush or nearly flush against neoprene seats.

If in doubt as to sealing ability. apply suction to carburetor side of assembly.

Leakage should be slight.

4. Check valve stopper clearance. If beyond tolerance. replace valve stopper.

Valve stopper clearance: 9.7 ± 0.3 mm (0.38 ± 0.012 in) 6. If disassembly of the reed valve assembly is required. proceed as follows: a. Remove Phillips screws securing stopper plate and reed to reed block. Handle reed carefully. Avoid scratches and do not bend. Note from which side of the reed block the reed and stopper plate were removed. Re-install on same side.

NOTE:-------------------------During reassembly. note the cut in the lower corner of the reed and stopper plate. Use as aid to direction of reed installation.

3-12

1981 SR540E

3-4. SILENCER JOINT 1. To protect the silencer joint against deformation, a steel band is used.

-CAUTION: - - - - - - - - - - A deformed silencer joint will result in an imbalance of temperatures of the right and left spark plugs. Don't forget installing the band.

b. During reassembly, clean block, reed and stopper plate throughly. Apply a holding agent. such as "Lock-Tite" to threads of Phillips screws. Tighten each screw gradually to avoid warping.

Torque: 0.08 m-kg (0.6 ft-Ib) 7. During reassembly of the reed valve assembly and manifold, install new gaskets and torque the securing bolts gradually and in a crisscross pattern to the proper torque.

1. Silencer joint 2. Band

2. Assembly procedure a. The band has six holes. Install the band so that its largest hole fits over the largest projection on the silencer joint and other small five holes over the protuberances one by one.

Reed valve securing bolt torque: 1.0 m-kg (7 ft-Ib)

3-3. FUEL PUMP

NOTE: Pull the projection using pliers so that the band tightly fits the silencer joint.

Check to see if fuel moves from tank to carburetor, and if any fuel leaks from pipe joints or fuel pump body.

Replace fuel pump assembly as required.

b. Cut off the tip of the projection.

1. Fuel pump¡

3-13

1981 SR540E

CHAPTER 4. POWER TRAIN 4-1.

4-2.

4-3.

4-4.

DRIVE ............................................................................................................................. 4-2

A.

Sheave adjustment .............................................................................................. 4-2

B.

Primary sheave ..................................................................................................... 4-3

C.

V-belt. .....................................................................................................................4-8

D.

Secondary sheve ..................................................................................................4-8

E. F.

Chain housing .................................................................................................... 4-12 Front axle ............................................................................................................ 4-16

BRAKE ......................................................................................................................... 4-19

A.

Disassembly ....................................................................................................... 4-19

B.

Inspection ........................................................................................................... 4-19

C.

Reassembly ........................................................................................................ 4-19

D.

Adjustment ......................................................................................................... 4-19

SUSPENSiON ............................................................................................................. 4-20 A.

Removal ................................................................................................................ 4-20

B.

Inspection ........................................................................................................... 4-21

C.

Slide rail suspension adjustment ................................................................... 4-22

D.

Installation ......................................................................................................... 4-24

DRIVE TRACK ............................................................................................................ 4-24

A.

Removal ............................................................................................................. 4-24

B. C.

Inspection .......................................................................................................... 4-24

D.

Adjustment ........................................................................................................ 4-25

Installation ......................................................................................................... 4-24

1981 SR540E

CHAPTER 4. POWER TRAIN 4-1. DRIVE

A. Sheave adjustment Use the sheave gauge to check the following: • Center to center distance between the primary and secondary sheaves.

• Off-set between the inside edge of the sheaves.

• Alignment of sheaves.

r-----

1. Sheave gauge

CD----1 1

If any of these is incorrect. proceed as follows: 1. Loosen the engine mounting nuts.

2. Adjust sheave distance, off-set and alignment by moving the engine back, forth or sideways.

1. Sheave distance

270~~ mm(10.63~gll in)

2. Sheave off-set 11 ± 0.5 mm (0.433

± 0.020 in)

Tool name

Tool No.

Sheave gauge

90890-01702

Sheave distance check Sheave distance:

o

+0

270 ~3 mm (10.63 -0.11

Sheave off-set: 11 ± 0.5 mm (0.433

in)

± 0.020 in)

NOTE:-------------If sheave off-set is not adjusted at above procedure, remove the secondary sheave assembly, and adjust the sheave off-set by installing or removing the plate washers from the secondary shaft.

1. Sheave gauge

Sheave offset/alignment check Place the sheave gauge against inner surfaces of the primary fixed sheave and the secondary sliding sheave. If t,/le sheave gauge contacts the sheaves at four points as illustrated, the offset is correct.

Parts name

NOTE:------------Be sure to remove the V-belt before adjusting the sheave offset.

4-2

Thickness

Plate washer (90201-25526)

2 mm (0.08 in)

Plate washer (90201-25527)

1 mm (0.04 in)

1981 SR540E

1. Primary fixed sheave puller

CAUTION: - - - - - - - - - - , Must be installed the washers at least 2 pieces (3 mm or more thickness).

2. Disassembly a. Install the sheave sub-assembly tool to the primary sheave.

3. Tighten the engine mounting nuts.

Tightening torque: 5.2 m-kg (37.6 ft-Ibl

Tool name

Tool No.

Sheave sub-assembly tool

90890-01858

B. Primary sheave 1. Removal a. Remove the V-belt. b. Straighten the lock washer tab. and remove the primary sheave mounting bolt. using the sheave holder.

Tool name

Tool No.

Sheave holder

90890-01701

1. Sheave sub-assembly tool

b. Loosen the six bolts securing the primary sheave cap and sliding sheave. c. Remove the sheave subassembly tool.

The primary sheave cap and sliding sheave can now be disassembled.

3. Inspection a. Check the tapered ends of the crankshaft and primary fixed sheave for scratches. If scratched unduly. replace.

If scratches are minor. burnish with emery cloth. b. Check the primary sheave cap bushing and sliding sheave bushing for wear. If beyond tolerance. replace the bushing.

1. Sheave holder

c. Remove the primary sheave assembly. using the primary fixed sheave puller and sheave holder.

Tool name Primary fixed sheave puller

Bushing clearance, limit

Tool No. 90890-01897

Primary fixed sheave attachment 90890-01899

4-3

Small bushing

Large bushing

Inside

0.25 mm (0.01 in)

0.25 mm (0.01 in)

Outside

0.25 mm (0.01 in)

0.25 mm (0.01 in)

1981 SR540E

NOTE:----------------------~

If bushing is installed tightly, remove the bushing using the bushing tool.

Tool name

Tool No.

Bushing tool

90890-01883

1. Bushing tool

c. Check the compression spring for fatigue. If excessively fatigued, replace. d. Check the spider and roller for smooth movement and wear. e. Check both sheaves for warping. If warped, replace.

4. Adjustment The primary sheave tuning should be set according to the altitude.

~

Setting parts

Sea level (Std.) (Up to 1 500m (5000 ftl)

High altitude (About 1500m (5000 ft) or more)

90501-50500

90501-55487

Red

Silver-Silver

25 kg

50 kg

Parts No.

Spring

Color code Set load Spring constant Parts No.

1.4 kg/mm

2.0 kg/mm

90261-06015

90261-0601 5

r---

~Counter sunk rivet

Set holes

Rivet

0 0

Weight

Parts No.

8L9-17632-00

44

r9\

'6

No rivet

0 8L8-17632-00

1981 SR540E

NOTE:-------------------------On the sea level (Up to 1500 m). if engine power is poor with snow condition. adjust sheave at the high altitude setting. a. Compression spring Clutch engagement rpm must be adjusted to specification using on optional compression spring. b. By changing the position and quantity of primary weight rivets. the thrust of weight can be changed, and thus the engine rpm at which the clutch is shifted can also be changed. (As a result. the engine rpm at which the clutch is engaged can be changed.)

5. Reassembly a. Adjust the slider button-to-guide clearance using shims as required under the slider button.

Slider button-to-guide clearance: 0", 0.2 mm (0", 0.008 in)

CAUTION: - - - - - - - - - - - - .

The rivets for three weights must be in the corresponding positions.

Thickness Rivet

Shifting rpm rpm increases.

No rivet is in use

CD

®

1

CD®

rpm decreases.

8L9

O--CD O--®

4-5

Shim (90201-090A4)

0.3 mm (0.012 in)

Shim (90201-097 A8)

0.2 mm (0.008 in)

1981 SR540E

b. Oil the points shown in the illustration.

Do not apply the grease on the portion of X mark. For other parts. greasing is unnecessary.

2. When installing the spacer and collar to the spider. the spacer and the spider projections must be fitted to the collar slit.

-x Free from oil -

Greasing point

CAUTION:------------------~

When the bushing is replaced with new one, apply molybdenum disulfide grease to bushing lightly. Except for this, don't grease.

Lock washer

Spacer

~-~,

pin is removed for the greasing, replace it with new one.

-+--+-+-.

o

c. Install the sheave sub-assembly tool and tighten the cap. d. Tighten the six primary sheave cap bolts and remove the sub-assembly tool.

Tightening torque: 1.1 m-kg (8 ft-Ib)

c. Install the component parts to the sliding sheave and the sheave cap.

CAUTION: ------------------.......

Make sure that the primary sheave cap assembly slides in contact with the fixed sheave boss.

NOTE:-----------------------1. When installing the spider and primary sheave cap to the primary sliding sheave. be sure to align the X marks on the spider and sheave cap with that on sliding sheave.

4-6

1981 SR540E

f. Clean the oil off the tapered portion of crankshaft using a lacquer thinner.

No oil

e. With the spider projection being in the receiving recess in the collar, (on the sliding sheave side: see photo) g. Fit the primary sheave assembly to the tapered portion of crankshaft. h. Apply engine oil to the threaded portion of primary sheave bolt and its contact surface with spring washer.

put a mark on the sheave cap in line with either notch in the other end of the same collar.

This mark will later serve as an effective guide for confirmation of corrrect fitting.

i. Tighten the primary sheave mounting bolt, using the sheave holder. Next, lock the lock washer.

NOTE: Check the lock washer, and if damaged, replace with a new one.

4-7

1981 SR540E

Tightening torque: First tighten the bolt to a torque of A, then loosen it.

Retighten bolt to a final torque of B. A: 12 m-kg (87 ft-Ib) B: 6.5 m-kg (47 ft-Ib)

C. V-belt Check the drive V-belt for damage and wear.

If the width is less than specified value, replace with a new belt.

2. Inspection a. Check the ramp shoes on secondary sliding sheave for wear. Replace ramp shoes as required.

[ Wear limit: 26 mm (1.02 in)

1. New: 31.5 mm (1.24 in)

2. Wear limit: 26 mm (1.02 in)

b. Check the sheave bushing for wear. Replace the sheaves as required. c. Check torsion spring for fatigue. If excessively fatigued, replace. d. Check both sheaves for warpage. If warped replace.

3. Secondary sheave spring adjustment It is advisable to change the secondary sheave setting to correspond to the course and snow conditions. This is done by changing the secondary spring preload.

The spring seat (see illustration) has 4 spring holes. The spring tension (preload) can be adjusted by selecting a spring in the seat and twisting the seat to engage the sheave ramps. In this way the preload can be adjusted in 30° steps.

D. Secondary sheave 1. Disassembly a. Apply the brake and remove the secondary sheave mounting bolt. b. Remove the secondary sheave assembly and plate washers.

c. Remove the circlip and disassemble the secondary sheave component parts.

4-8

1981 SR540E

[Secondary spring setting] Course Setting factor

Trail and tour

Lake surface

Position of spring seat

Twist

Position of spring seat

Twist

Ice snow

Std.

Std.

No.2

180 0

Packed snow

Std.

Std.

Std. or No.2

Std. or 180 0

Std. or No.4

Std. or 240

Std.

Std.

Wet snow

0

Winding the spring more (e.g., from 30° to 60°) will increase the clutch shifting rpm and vise versa. Snow conditions will also require a change of the spring tension in orde to attain the standard shifting rpm. The spring tension must be greater on wet snow than on packed snow, and less tension is needed on icy snow.

Std. secondary spring:

PIN: 90508-45286 Color code: Yellow Std. secondary spring position: NO.3 Std. secondary spring twist: 210 0

a. Secondary spring position The spring seat is provided with four holes. Nos. 1 to 4, so that the secondary spring position can be changed as required.

4. Reassembly a. Grease the secondary shaft. and sliding sheave boss and mount the sliding sheave on the shaft.

Recommended grease: Molybdenum disulfide snowmobile grease

A. Spring seat

b. Secondary spring tension The secondary spring tension can be changed by moving the spring position from the free position in order to reset the clutch shifting RPM as required. The four holes are spaced at intervals of 30°.

Secondary spring position

Spring wind

No.1

30°,150°.270°

No.2

60°,180°

No.3

90°,210°

No.4

0°,120°,240°

4-9

1981 SR540E

Secondary Sheave Assembly

7 /

~

z?

11

. ~~,/13 / /

~.

12

14

~

"" ~'~/

Tightening torque: 2.3 m-kg (16.5 ft-Ib)

<J1]

Molybdenum disulfide snowmobile grease (Wear-resistant grease)

FWD

2 3

14

6 5

I Clearance: 0.1 ~ 1.0 mm

Tightening torque: 6.4 m-kg (46 ft-Ib)

10

Tightening torque: 6.4 m-kg (46 ft-Ib)

16

11

1 . Secondary fixed sheave compo 2. Secondary sliding sheave

10. Plain washer 11. Eccentric bearing

3. Lamp shoe

12. Bearing housing

4. Secondary spring seat

13."Bolt

5. Plain washer

14. Spring washer 15. Plain washer 16. Collar 17. Torsion spring

6. Circlip 7. Secondary shaft 8. Plain washer 9. Washer based bolt

4-11

1981 SR540E

E. Chain housing 1. Disassembly a. Remove the chain housing cap and drain the chain housing oil.

1. Eccentric bearing installer

e. Remove 3 bolts.

b. Apply the brake and remove the cotter pin and the drive sprocket nut and driven sprocket bolt.

f. Remove the brake caliper assembly.

(Refer to 4-2. Brake section)

c. Loosen the chain tensioner and remove the drive. driven sprockets and chain.

g. After removing the suspension assembIy, remove the two bolts mounting the chain housing. (Refer to 4-3. Suspension)

d. Remove the bearing inner race securing screw. and loosen the inner race by using eccentric bearing installer.

Tool name Eccentric bearing installer

Tool No.

90890-01851

4-12

1981 SR540E

2. Inspection a. Drive chain Except in case of oil starvation. the chain wears very little. If the chain has stretched excessively and it is difficult to keep the proper chain tension. the chain should be replaced. b. Drive. driven and chain tension sprockets.

Check sprocket for obvious wear. Replace sprocket as required. c. Bearing selection Check the chain case bearings and oil seals for damage. If damaged. replace.

h. Remove the chain housing assembly. i. Remove the brake disc and key.

3. Gearing selection The reduction ratio of driven sprocket to drive sprocket must be set according to the snow condition.

Many rough surfaces or unfavorable snow conditions; the driven/drive sprocket ratio should be made larger.

Few rough surfaces or better snow conditions; the ratio should be made smaller. j. Remove the secondary shaft complete.

a. Std. reduction ratios Drive chain sprocket

17 (PIN 878-17682-70)

Driven chain sprocket

31 (PIN 878-47587-00)

Chain (Links)

66 (PIN 94850-35066)

b. A guide to reduction ratios

Trail riding

High altitude (Up to 1500 m or more)

Lake course

Snow condition

ICY

Packed

Wet

ICY

Packed

Wet

ICY

Packed

Wet

Drive chain sprocket

Std.

Std.

16

Std.

Std.

16 or Std.

15

15

15

Driven chain sprocket

Std.

Std.

Std.

Std.

Std.

Std.

33

33

33

Chain Oinks)

Std.

Std.

Std.

Std.

Std.

Std.

Std.

Std.

Std.

sent the driven/drive sprocket ratios. while those in lower lines represent the number of chain links.

c. Sprocket ratio and chain link chart The following sprockets. drive and driven. and chains are available as options. The figures in upper lines repre-

4-13

1981 SR540E

~ sprocket

Teeth of driven sprocket 29

PIN 878-47548-90

31 PIN 878-47587-00

33 PIN 888-47587-10

35 PIN 878-47587-20

15

16

17

18

19

20

21

22

PIN 878

PIN 878

PIN 878

PIN 878

PIN 878

PIN 878

PIN 878

PIN 878

17682-50

17682-60

17682-70

17682-80

17682-90

17693-00

17693-10

17693-20

1.933 64

1.813 66

1.706 66

1.611 156

1.526 66

1.450 68

1.381 68

1.318 68

2.067 66

1.938 66

1.824 66

1.722 68

1.632 68

1.550 68

1.476 68

1.409 70

2.200 66

2.063 68

1.941

68

1.833 68

1.731 68 or 70

1.650 70

1.571 70

1.500 70

2.333 68

2.188 68

2.059 68 or 70

1.944 70

1.842 70

1.750 70

1.667 70 or 72

1.591 72

Chain links

Part No.

64

94890-03064

66

94850-35066

68

94850-35068

70

94850-35070

d. Install the drive and driven sprockets with chain.

Place the collar into the drive sprocket.

Tighten the drive sprocket nut and fit a new cotter pin. Don't forget to bend the cotter pin's ends. Tighten the driven sprocket bolt.

4. Reassembly a. Apply a low temperature grease to the chain housing oil seal lip. Install the secondary shaft complete with brake disc.

Tightening torque: Drive sprocket nut: 6.0 m-kg (43.5 ft-Ib) Driven sprocket bolt: 4.8 m-kg (35 ft-Ib)

NOTE:-----------------------Make sure woodruff key is properly seated in key way of secondary shaft. Install brake disc so that it aligned with the woodruff key. b. Use the two bolts to mount the chain housing to frame.

Tightening torque: 2.3 m-kg (16.5 ft-Ib)

e. Tighten the bearing inner race by using eccentric bearing installer.

c. Install the brake caliper assembly.

Brake caliper mounting bolt tightening torque: 4.8 m-kg (35 ft-Ib) 1. Eccentric bearing installer

4-14

1981 SR540E

Fill until oil begins to run out the screw hole.

f. Tighten the bearing inner race securing screw.

Recommended oil: Gear oil API "GL-3" SAE #75 or #80 Quantity: 250 cc (8.5 OZ)

Tightening torque: 0.6 m-kg (4.5 ft-Ib)

After adding oil. be sure to install and tighten the level screw and filler cap. i. Drive chain tension adjustment Remove the lock nut. Turn in the adjust bolt clockwise finger-tight. Then tighten the lock nut with a spanner while keeping the adjust bolt steady with the other spanner.

Chain free play: 8 '""""' 15 mm (0.32 '""""' 0.59 in)

g. Install the gasket and chain housing cap.

Tightening torque: 1.6 m-kg (11.5 ft-Ib)

Lock nut tightening torque: 3.5 m-kg (25 ft-Ib)

h. To add gear oil. the filler cap and oil level screw should be removed.

1. Chain free play 8 ~ 15 mm (0.3 - 0.6 in)

1. Adjusting bolt

1. Oil level screw

4-15

2. Lock nut

1981 SR540E

F. Front axle 1. Removal a. Remove the slide rail suspension assembly. (See 4-3. Suspension) b. Remove the speedometer gear housing and the joint.

c. Remove the nut mounting the front axle. collar. and bearing. (Lock the front axle by applying the brake.)

':1 {r11,.1

"I ~ , r+~

'---'" 1. Set bolt

2. Guide wheel

f. To remove the wheel sprocket from the axle. loosen the collar and push out using a press.

2. Inspection Check wheel sprocket for damage and wear. Replace wheel sprocket as required.

3. Installation a. When installing the wheel sprocket to the front axle. position the wheel sprockets on the front axle as shown.

Use a press.

d. Remove the chain housing cap.

(Refer to "Chain housing".) Drain oil and remove the chain driven sprocket. e. Loosen set bolt CD using a 3 mm hex. wrench and slide guide wheel ÂŽ. before pulling out the front axle.

4-16

1981 SR540E

FWD

l!

104 mm (4.09 in)

104 mm (4.09 in)

I

Tightening torque: 0.55 m-kg

59mm :

(2.32i~

Then. slide guide wheel ÂŽ to the left until it comes in full contact with collar <D and secure set bolt @ using a 3 mm hex. wrench.

b. Be sure the sprocket teeth are aligned as shown. After positioning. tighten the collar and clamp.

Tightening torque: 0.55 m-kg (4 ft-Ibl

c. Apply a low temperature grease to the front axle. and install the collar. bearing. belleville washer and front axle nut.

Tightening torque: 8.5 m-kg (61.5 ft-Ibl 1. Set bolt

iJ

4-17

1. Collar

FWD

2. Guide wheel

3. Set bolt

1981 SR540E

d. Install the speedometer gear housing together with bearing cover and joint.

Tightening torque: 2.3 m-kg (16.5 ft-Ib)

FWD

1. Bearing cover Joint Speedometer gear housing Collar Guide wheel 6. Collar 7. Set bolt 8. Bearing 9. Belleville washer 10. Nut

2.

3.

4.

5.

e. Apply a low temperature grease to the chain case oil seal. and insert the righthand side of front axle into chain case through drive track.

Tighten the front axle with chain driven sprocket.

Tightening torque: 4.8 m-kg (35 ft-Ib)

f. Install the chain housing cap and add oil.

(See "4-1-E-4. Chain housing") g. Install the slide rail suspension assembly.

(See "4-3-0. Suspension installation")

4-18

1981 SR540E

4-2. BRAKE

C. Reassembly 1. Apply a low temperature grease to the back up plate shaft and screw cam.

A. Disassembly 1. Remove the brake cable from the brake caliper.

2. Remove the brake caliper assembly.

2. Install the brake caliper with brake pads to the chain housing.

3. Remove the brake pads.

Tightening torque: 4.8 m-kg (35 ft-Ib)

NOTE:-----------------------For brake disc removing. refer to "4-1-E-1.

Chain housing".

3. Install brake cable to the caliper and brake lever.

CAUTION: - - - - - - - - - - ,

B. Inspection 1. Check the pads for damage and wear. If the thickness is less than specified below. replace pads as a set.

Apply a small amount of antifreeze grease to the contact areas of the brake wire with brake lever stopper surface, but do not apply a grease between the outer wire and inner wire.

Wear limit: 9.5 mm (0.37 in)

D. Adjustment 1. Loosen the lock nut (j) and turn the adjusting bolt ÂŽ to set the "L" distance to the specification below.

1. New: 13.5 mm (0.53 in) 2. Wear limit: 9.5 mm (0.37 in)

2. Check the brake disc for warpage. If warped. replace.

3. If the brake lever will not return smoothly to the rest position because of a fatigued return spring. replace the return spring.

L

= 57 mm (2.24 in)

Next. lock the adjusting bolt with the lock nut.

4-19

1981 SR540E

3. After locking the nut @, insert the feeler gauge again into the clearance and make sure the clearance is 0.15 mm.

1. Lining pad 2. Brake disc 3. Screw

4. Back-up plate 5. Nut 6. Brake wire

7. Lock nut B. Adjusting bolt

CAUTION:~----------------~

After step 1, be sure to take step 2, and3.

Clearance

= 0.15 mm

2. Loosen the nut @ and back out the screw @.

Insert a 0.15 mm feeler gauge between

1t

FWD

O.15mm

the lining pad CD and brake disc ÂŽ , and by turning the screw @ so that the clearance between the pad and disc is 0.15 mm.

4-3. REAR SUSPENSION A. Removal

NOTE:-------------------------

1. Adjusting bolt 2. Lock nut

It is advisable to loosen the track adjusting nut and the rear axle nut.

1. Remove the two front pivot shaft mounting bolts and four rear pivot shaft mounting bolts.

4-20

1981 SR540E

WARNING (Rearshock):----___.

This shock absorber contains highly pressurized nitrogen gas.

Read and understand the following information before handling the shock absorber. The manufacturer cannot be held responsible for property damage or personal injury that may result from improper handling.

1) Do not tamper with or attempt to open the cylinder assembly. Injury may result.

2) Do not subject shock absorber to an open flame or other high heat. This may cause the unit to explode due to excessive gas pressure.

3) Do not deform or damage the cylinder in any way. Cylinder damage will result in poor damping performance.

4) Gas pressure must be released before disposing of the shock absorber.

To do so, drill a 2 '" 3 mm (0.08 '" 0.12 in) hole through the cylinder wall at a point 10 '" 15 mm (0.4 '" 0.6 in) above the bottom of the cylinder.

2. Remove the slide rail suspension assembly.

B. Inspection 1. Check to see if slide runners are worn excessively. If the slide runner thickness is less than specified value. replace slide runner.

Wear limit: 10 mm (0.4 in) Slide runner securing screw tightening torque: 0.45 m-kg (3.3 ft-Ib)

~

- - - - ----- - ------

-- !

-r

10~ 15mm(0.4~0.6in)

2 1. Wear limit: 10 mm (0.4 in) 2. New: 15 mm (0.6 in)

~

3 mm

(0.08~

0.12 in)

I

2. Check the suspension wheel for damage.

If damaged. replace it.

3. "DE CARBON" type shock absorber (Rear).

4-21

1981 SR540E

This adjustment will greatly affect the stability and handling.of the machine as well as the side slip of the track while turning a corner.

WARNING: - - - - - - - - - - - . . , Wear eye protection to prevent eye damage from escaping gas and/or metal chips. a. Check the rod, and if it is bent or damaged, replace the shock absorber. b. Check for oil leakage. If oil leakage is evident. replace the shock absorber. c. By compressing the shock absorber, check to see there is no gas leakage.

C. Slide rail suspension adjustment The setting of suspension greatly affects the stability and steering of the machine. Therefore, it is necessary to adjust the suspension setting according to course conditions and rider's driving technique.

1. Stopper band setting The height (L) of the front suspension can be properly adjusted by changing the length of the stopper band.

NO.5

No.4

Standard setting: No. 1 hole from the bottom

No.3 No.2 No.l-+-o4f-STD

Tightening torque: 0.38 m-kg (2.75 ft-Ib)

1. Stopper band

Height

Handling

Track side slip

Performance of straight running

Bumping and pitching

Riding comfort

Lower

Easy

Increase

Poor

More

Poor

Higher

Hard

Decrease

Good

Less

Good

2. Rear spring The rear spring is a determining factor in machine stability.

Consider the ground surface condition

and the rider's weight when setting rear springs. The suspension should be set as soft as possible, unless it impairs the stability of the machine.

4-22

1981 SR540E

1. Normal riding (less gap) Std. weight rider

Course or rider's weight

2. Trail riding (mo~e gap) Heavy weight rider

Normal riding (less gap) Std. weight rider

Trail riding (more gap) Heavy weight rider

Rear spring set position

3. Additional wheel installaion When the machine is driven on icy surfaces for a prolonged period of time (for instance. trail riding). additional wheels

should be installed to protect the slide runners from fast wear. This is not advisable for a race because the suspension will be adversely affected.

1. Suspension wheel

2. Washer

3. Bolt Tightening torque: 2.0 m-kg (14.5 ft-Ib)

4-23

1981 SR540E

D. Installation Grease the slide rail suspension as indicated by arrows in the illustration.

For easy installation of the slide rail suspension in the frame. proceed as folloWs .

.

1. Fully loosen the drive track adjusting screws.

2. Place the slide rail suspension into track and fit the forward pivot shaft using washers and bolts.

--- - - - -

-----..

4-4. DRIVE TRACK A. Removal 1. Remove the slide rail suspension assembly and front axle.

(See 4-1- F. Front axle and 4-3. Suspension section)

NOTE:-------------------------Install bolts finger-tight. Bolts will be tightened to proper torque when slide rail installation is complete.

B. Inspection Check drive track and clips for cracks. damaged or wear. Replace drive track or clip as required.

3. Fit the rear pivot shaft to the frame. The rear pivot shaft is being forced toward the rear by the shock absorber.

To assist in rear shaft installation. keep the shaft forward by using an iron bar.

c.

Installation Install drive track assembly as illustrated.

(See 4-1-F. Front axle and 4-3. Suspension section)

NOTE:------------------------When installation of .slide rail is complete. tighten front and rear bolts to proper torque.

Tightening torque: Front pivot shaft mounting bolts: 6.4 m-kg (46 ft-Ib) Rear pivot shaft mounting bolts: 6.4 m-kg (46 ft-Ib)

Turning direction

4. Adjust the track tension by turning the track adjusting nuts. For adjustment. refer to "4-4-0. Track adjustment".

4¡24

1981 SR540E

The adjustment should be made in the following sequence: 1. Turn the track by running the engine.

2. Loosen the rear axle lock nuts. and turn the track adjusting nuts both right and left through the track window using a box wrench to align the track with the slide rail.

D. Adjustment WARNING: - - - - - - - - - - , A brokert track. track fittings. or debris thrown by the track could be dangerous to an operator or bystanders. Observe the following precautions: 1) Do not allow anyone to stand directly behind the snowmobile when starting forward.

2) When the engine is running and the track is engaged with the snowmobile placed on its side. do not allow anyone to stand behind or on the track side of the snowmobile.

The operator must stay on the seat (top side of the machine).

3) Never lift the rear of the snowmobile to allow the track to turn while the engine is running. Stop the engine and prop up the rear with a suitable stand. Never stand behind the machine when the track is spinning.

4) Never install studs (cleats) closer than three inches form the edge of the track.

5) Replace any track tha is damaged to. the depth where fabric reinforcement material is visible. Inspect track condition frequently.

NOTE:------------------------Track tension adjustment is possible without removing the split pin.

1. Rear axle nut 2. Split pin

The track tension should be so adjusted that when pulled at its window in the track center by a force of 10 kg (22 Ib) using a spring scale. the deflection should be as specified below.

1. Adjusting nut

3. After the adjustment specified in 2

Track deflection: 25", 30 mm/1 0 kg (0.98 '" 1.18 in/22 Ib)

above. pull the track window at the center of the track with a force of 10 kg (22 Ib) using a spring scale. The track deflection should be as specified.

4. By repeating the procedures in 1. 2 and 3 above. the track should be brought in alignment with correct tension.

5. After making sure all adjustments are correct. tighten the rear axle nut.

25 -':':30¡rnm.. ., (0.98 -1.18in;

.

;

.

:~

Tightening torque: 8.0 m-kg (58 ft-Ib)

4-25

1981 SR540E

No good

Good

Slide runner

Slide runner

No good Slide runner

Track

'-¡~""~-II---<"""""--===t-_ Track metal

,>

1-..........'--1H-~ __.......~~-'

Forward

Gap between slide runner and edge of track window.

Track metal

.0-

iJ,

Forward

Forward Gap between slide runner and edge of track window.

When shifted to right: Tighten the right track adjusting bolt. and loosen the left track adjusting bolt.

When shifted to left: Tighten the left track adjusting, bolt and loosen the right track adjusting bolt.

4-26

1981 SR540E

CHAPTER 5. CHASSIS 5-1.

5-2.

TELESCOPIC STRUT SUSPENSION .......................................................................... 5-2 A.

Disassembly ........................................................................................................... 5-2

B.

Inspection ............................................................................................................... 5-5

C.

Installation .............................................................................................................. 5-7

FRONT SHOCK ABSORBER ("DE CARBON" TYPE) ........................................... 5-14 A.

Telescopic strut suspension setting ................................................................. 5-14

5-3.

"DE CARBON" TYPE SHOCK ABSORBER ............................................................ 5-18

5-4.

STEERING .................................................................................................................... 5-19 A.

Installation ., ......................................................................................................... 5-19

B.

Adjustment ...................................................................................................·······5-19

5-5.

OIL TANK ..................................................................................................................... 5-20

5-6.

FUEL TANK .................................................................................................................. 5-20

5-7.

SKIS .........................................................................................................······················5-21 A.

Inspection ............................................................................................................ 5-21

1981 SR540E

CHAPTER 5. CHASSIS 5-1. TELESCOPIC STRUCT SUSPENSION A. Disassembly 1. Removing the ski assembly. a. Raise the snowmobile side appropriate inclination.

to

an

b. Remove the split pin. c. Remove the bolt with hole.

1. Set bolt

NOTE: - - - - - - - - - - - The set bolt needs only loosening; not removing. b. Remove the bolt with hole from the lower front arm.

d. Remove the ski ass¡y.

c. Loosen the lower end bracket tightening nuts.

2. Removing the lower end bracket.. a. Loosen the set bolt.

5-2

1981 SR540E

c. Remove the 4 bolts tightening the absorber holder.

NOTE:--------------------____ The nuts needs only loosening; not removing. d. Remove the lower end bracket.

Then remove the absorber holder.

3. Removing the compression spring. a. Remove the rubber protector.

d. Remove the top one of the 2 bolts employed for double tightening.

b. Remove the 3 nuts tightening the absorber holder top.

5-3

1981 SR540E

e. Remove the bottom one of employed for double tightening.

f. Remove the bearing holder and collar.

g. Remove the spring seat and compression spring.

CAUTION: - - - - - - - - -......

When removing the nut, hold the top of the damper sub-ass'y by spanner.

Never score the rod of the damper subass'y with the pliers or the like.

NOTE: Suspension setting can be changed by using a different compression spring.

4. Remove the damper sub-ass¡y.

5. Removing the outside arm a. Remove the bolt with hole from the upper front arm.

5-4

1981 SR540E

f. Remove the O-rings washers. and outside ami.

b. Remove the 4 panhead screws.

c. Put down the plastic hood.

B. Inspection 1. Damper sub-ass'y a. Check the rod for scores or oil leakage or bends. Replace as required.

d. Remove the bolt from the linkage of the outside arm. e. Remove the circlip.

b. Check the rod for an automatic return when it is pushed in and then released.

Unless it returns. check the gas pressure. and adjust to the standard figure below.

Standard static pressure: 15 kg/cm 2 (213 psi)

5¡5

1981 SR540E

3. Front arm Check the bush for wear. Replace as required.

c. Check the rotor for a smooth rotation.

4. Outside arm Check the bush for wear. Replace as required.

NOTE:--------------------___ The bearing has no need grease application because it is a grease-sealed one.

2. Lower end bracket Check lower end bracket for a crack.

Replace as required.

Check the bush for wear. Replace as required.

5. Stopper of ski ass'y Check the rubber stopper for a crack or lack of flexibility. Replace as required.

5¡6

1981 SR540E

C. Installation

l---r-l--$ --1

Tightening torque: (1.6 m-kg, 11.6

I

I

~

~

I

0'

-

I

..".,....... -'=---1

-::::=====?:;,...,-~~~

I I

~ .

I J ---

I

@9

.~

II I

I

Collar I

I

I I

~:I

II

I

F'l t::J

I

Damper

'I'

WT"'Y I

I

I

!

I

I

I

I

I

,,~I

: I I

_ I L. __________ .J

Lower end Bracket

Use Lock Tight

Tightening torque: (2.1 m-kg, 15.2 ft-Ibl

....... Greasing point (ESSO beacon 3251

5-7

1981 SR540E

C-1. Damper sub-ass'y (Strut) Installation 1. Before inserting the damper sub-ass'y into the hole in the frame complete, make sure of the quantity of grease in the frame complete, and add grease as required.

2. Fit the lower seat bearing and compression spring.

Then fit the upper seat bearing with the stop bump and the collar.

Specified grease: ESSO beacon 325

3. Install the housing bearing and washer.

Then tighten the nut.

CAUTION:------------------~

When inserting damper sub-ass'y into the frame complete, special care is required not to damage the oil seal and bushing.

5-8

1981 SR540E

Tightening torque: 0.5 m-kg (3.6 ft-Ib)

4. Tighten the nut for double tightening.

Tightening torque: 1.6 m-kg (11.6 ft-Ib)

5. Allow the holder bearing to be positioned in the direction as illustrated.

5-9

1981 SR540E

6. Install the absorber cover with a paper protector and tighten the 4 bolts. Then the 3 nuts on top of the absorber cover.

C-2. Outside arm, front arm and ski compo installation 1. Before installing the O-ring, washer and circlip, apply grease to the boss on the frame complete. Then install the circlip.

1. Paper protector

Specified grease: ESSO beacon 325 2. Tighten the bolt for securing the linkage.

3. Tighten the bolts with hole to the upper and lower front arms a. Apply grease to the collar surface and to the lower front arm interior.

Specified grease: ESSO beacon 325

Tightening torque: 0.6 m-kg (4.3 ft-Ibl

b. Be sure to install plastic washers. c. After tightening the nut, insert the split pin; then, spread it on the end.

Put a rubber protector on the absorber cover.

Tightening torque: 4.3 m-kg (31.1 ft-Ibl

5-10

1981 SR540E

CAUTION:------------------~

Note that the upper and lower front arms differ in shape. Be careful not to reverse their positions. These are marked "UPPER" and "LOWER".

4. Apply grease the bracket interior for collar. Then insert the lower end bracket to the damper sub-ass'y and tighten the bolt with hole to the lower front arm, and insert the split pin.

CAUTION: - - - - - - - - - - , Lower end brackets differ in type between the right and left. Locate the bracket with its slit outside and with its set bolt hole forward.

5-11

.....

U)

CO

en

::0 U1

~

m

7

~,(18

~ .-.J a~

~ ----. . ' -3-r "" . '~~\c13 3~ 2. I------,i,

.1

?Jf3"'~ 9

12

0

R

0

o

I

o

o

V· l I',.

22" /~,~: , ~Q"'~c1 -""T" I' i

l

o

20~.'lr~~.'~2t, _---~ T--J 0 ~ ~ r--r~i-~l· ,~. . G'..~"~~1~ ~-----------

If! .....

i

I'J

21

16

10 11

1. Lower end bracket sub-ass'y left

12.

13.

14.

15.

16.

17.

Set bolt Bolt with hole (Long) Washer Ski complete Collar (Long) Nylonnut(10mm)

8. * Bracket right 9. Stopper right 10. Nylon nut (8 mm)

18.

19.

20.

21.

Split pin Bolt with hole (Short) Plain washer (White plastic) Collar (Short)

11. Plain washer

22. Cap

2.

3.

4.

5.

*Bracket left *Bimetal formed bush *Stud bolt (Short) *Stud bolt (Long)

6. Stopper left 7. Lower end bracket sub-ass'y right

1

c.'. . . . ~.

'L?7~ -..

12

i

---_---,

11 10

1·~~V 17

~

~.

~

/

~4~ 13

~

15

1i ~

3:

.

~~~

I

4

____

1981 SR540E

5. Tighten the nuts.

Tightening torque: 0.2 m-kg (1.4 ft-Ib)

7. Insert the stopper into the ski ass'y.

Tightening torque: 2.1 m-kg (15.2 ft-Ib) CAUTION:---------~

CAUTION: ------..,.......--~ The cap is intended to protect the rubber valve in the damper sub-ass'y.

Never fail to put it on. Make sure that the cap and damper sub-ass'y are securely fitted in the bracket.

Loose fit will cause the bracket to be damaged.

Note that stoppers differ in shape between the right and the left. These are marked "L" and "R".

8. Install the ski ass'y and tighten it by means of the bolt with hole. Then secure with the split pin.

6. Tighten the set bolt.

Tightening torque: 4.3 m-kg (31.1 ft-Ib) CAUTION: - - - - - - - - - In assembly, the set bolt should be tightened at the end of assembly. Also apply a locking agent to the bolt. When disassembling, do not forget to loosen it, or the shock absorber can not be pulled out.

CAUTION:---------_ Pay attention to the direction in installing the ski ass'y to the strut ass'y.

Contact of the cap with the damper ass'y will result resistance to ski toe upand-down movement, thus making it difficult for the ski to follow the snow surface properly.

Specified holding agent: Nejilock super

5-13

1981 SR540E

5-2. FRONT SHOCK ABSORBER ("DE CARBON" type) A. Telescopic strut suspension setting The telescopic strut suspension setting factors can be selected from the following table according to the rider's preference.

1. Compression spring

Parts No.

Std. spring

Optional spring

90501·75612

90501·70584

1.6 (89.6)

0.8 - 1.2 (44.8 - 67.2)

Red

No Color

Spring constant kg/mm (Ib/in) Color

2.

Damper sub assembly Std. damper sub assembly Parts. No.

Dumping force

8L9·22401·00

Tension

84 ± 15 kg/0.8 m/s (185 ± 33Ib/2.6 ft/s)

Compression

46 ± 5 kg/0.8 m/s (101 ± 11 Ib/2.6 ft/s)

*The optional parts will be sold next December.

3. Gas pressure adjustment The gas pressure of front shock absorber can be adjusted using the special tools.

By increasing the gas pressure, the initial load is increased. (The suspension becomes hard to compress but stretches· easily.)

By decreasing the gas pressure, the initial load is decreased. (The suspension can contract easily but is hard to stretch.)

Gas pressure kg/cm 2 (psi)

Maximum

S.T.D.

Minimum

20 (284)

15 (213)

13 (185) (at 20°C degree)

CAUTION: - - - - - - - - - . . . . . , 1) Never make gas pressure checking and adjustment under temperatures below

oDe.

2) Do not use any other gas than nitrogen gas. The gas pressure should always be in specified range.

5-14

1981 SR540E

- - - 13 kg/cm 2 (185 psi) - - 15 kg/cm 2 (213 psi) - - - 20 kg/cm 2 (284 psi)

Tension

Cl

:::: w

u

a: o LL (!)

Z Q.

:?!

<{

o

,

-

'~---------------:~/

-----== -

=--

Compression

Stroke: 100 mm (3.93 in) Speed: 288 rpm

a. Special tools To check the nitrogen gas pressure or refill with nitrogen gas, the following tools are required.

Gauge set ............. 90890-01160 CD Hose .............. 90890-01158 @ Joint gauge ......... 90890-01161 @ Joint holder ........ 90890-01162 @ Joint hose end ...... 90890-01163 @ Joint cover ......... 90890-01164 ÂŽ Needle ............ 90890-01167 (j) Check gauge ........ 90890-03063 ÂŽ Joint .............. 90890-01165

b. Checking nitrogen gas pressure NOTE:------------Oil the injection needle before inserting it in the Gas adjustment valve.

To check the nitrogen gas pressure in the gas chamber, use the check gauge. To measure the gas pressure, and insert the oiled needle into the gas chamber.

5-15

1981 SR540E

4) Adjust the gas pressure to a desired value. Hold this pressure for one minute.

Maximum static pressure: 20 kg/cm2 (284 psi) CAUTION:------------------~

Do not over-pressurize the gas chamber.

Gradually increase the regulator setting until the required pressure is reached.

5) Close the nitrogen bottle main valve and remove the injector needle, from the housing cap. This will allow the nitrogen pressure in the hose to flow out. Back off the pressure regulator. d. Bleeding nitrogen gas To bleed the nitrogen gas, oil the injector (needle) and thrust it into the housing cap. The gas can easily be bled.

c. Refilling nitrogen gas To refill with nitrogen gas, proceed as follows: 1) Fit the injector needle onto the nitrogen pressure hose and oil the injector needle

lightly.

2) Close the regulator off completely by turning the knob in a counterclockwise direction. Open the nitrogen bottle main valve.

3) Insert the injector into the rubber valve in the housing cap.

NOTE:-------------1.

After nitrogen gas refilling or bleeding, screw in the joint cover over the check gauge.

2. When using the check gauge to verify the nitrogen pressure, approximately 0.351 kg/cm 2 will be lost. Do not use the regulator pressure gauge to check the 3.

4.

NOTE:------------------------Support the injector needle with your hand during pressurization.

5-16

pressure in the unit.

Take care not to damage nitrogen gas needle during insertion. Replace safety sheave when needle is not in use.

As the suspension is used, it will heat up, thus increasing the nitrogen gas pressure. It is recommended that gas pressure be adjusted and check at room temperature so consistant results can be achieved.

1981 SR540E

r----

Input pressure indicator

r----Cylinder pressure indicator r---Valve (1)

Joint ----____.

Valve (2) -----H"---~

Nitrogen cylinder

Hose------"<" Injector (Oil before inserting) - - - - - - ,

4. Damper unit pressure adjustment in a snowmobile.

1. Removing the ski assembly a. Raise the snowmobile side appropriate inclination. b. Remove the split pin. c. Remove the bolt with hole.

to

an

2. Gas pressure adjustment a. Refilling nitrogeen gas.

d. Remove the ski assembly.

5-17

1981 SR540E

NOTE:-----------------------Gas pressure adjustment is possible on the damper sub-assembly and lower end bracket without removing them.

1. Damper sub-assembly¡¡ 2. Cap

5-3. "DE CARTON" TYPE SHOCK ABSORBER WAR N ING: - - - - - - - - - - - , This shock absorber contains highpressure nitrogen gas. To prevent the danger of explosion. read and unders-. tand the following information before handling the shock absorber.

The manufacturer can not be held responsible for property damage or personal injury that may result from improper handling.

1. Never tamper or attempt to disassemble the cylinder.

2. N ever throw the shock absorber into an open flame or other high heat.

The shock absorber may explode as a result of nitrogen gas expansion.

3. Take care not to scratch the contact surface of the piston rod with the cylinder; or oil could leak out. Do not deform or damage the cylinder in any way. Cylinder damage will result in poor damping performance.

4. Never attempt to remove tthe plug at the bottom of the cylinder. It is very dangerous to remove the plug.

5. When scrapping the shock absorber. follow the instructions on disposal.

3. Lower end bracket

b. Checking nitrogen gas pressure.

NOTE:------------------------After refilling the nitrogen gas. it is not necessary to check the pressure.

Notes on disposal Before disposing the shock absorber. be sure to extract the nitrogen gas.

In the case of rear shock absorber. drill a 2 ,...., 3 mm (0.08 ,...., 0.12 in) hole through the cylinder at a position 10,...., 15 mm (0.4 ,...., 0.6 in) from the bottom of the cylinder.

The front shock absorber is chromed. Remove this chrome deposit from the absorber before drilling a hole in it. The drilling should be done in the groove as illustrated. At this time. wear eye protection to prevent eye damage from escaping gas and/or metal chips.

c. Releasing nitrogen gas.

Nitrogen gas refilling. releasing. or checking should be done on minimum necessary occasions; otherwise. it may damage the rubber valve with the consequent pressure leakage.

5-18

1981 SR540E

10 2

~

~

15 mm (0.4 ~ 0.6 in)

3 mm (0.08 ~ 0.12 in)

Tightening torque: 2.3 m-kg (16.5 ft-Ib)

Rear shock absorber

.....

[JJ

~

3. Connect the steering relay rod to the steering column using the flange nut.

Install a new cotter pin.

L

Front shock absorber

5-4. STEERING A. Installation 1. Secure the steering relay rod (with universal joint attached) to the outside arm with the flange nut and cotter pin.

Tightening torque: 4.7 m-kg (34 ft-Ib)

Tightening torque: 4.7 m-kg (34 ft-Ib) B. Adjustment 1. Ski Hold the handlebar straight and check to see that the skis are parallel. If not, loosen the steering relay rod lock nut. and by turning the steering relay rod in or out. adjust the ski toe-out to specification (see below).

Ski stance: 880 mm (34.6 in) Ski toe-out: 0 mm (O in) 2. Install the steering column on the frame. Before this operation, coat the steering lower and upper bearing with grease. Tighten the nuts and bolts, and bend the lock washer tab.

Steering relay rod tightening torque: 4.7 m-kg (34 ft-Ib)

1981 SR540E

5-5. OIL TANK

11 Front A--I-.

1. Check the hose from the tank to the oil pump for obstructions such as pinching or other damage.

2. It is advisable that the oil filter be replaced with a new one each season.

1. Ski spindle center A - C = 0 mm (0 in) B. Ski width

1. Oil filter

5-6. FUEL TANK 1. Check for missing pipe retaining dips.

2. Check pipes for flattening caused by tank.

3. Check the breather pipe for correct routing.

Check clamps for looseness.

The breather pipe should be routed so that no fuel leakage will result from severe vibration. shock and/or banking of the vehicle.

For routing. refer to piping and wiring diagrams.

4. It is advisable that the fuel filter be replaced with a new one each season.

If the filter is faulty (obstructing the fuel flow or having a breakage in the element). it should be replaced as an assembly unit.

1. Fuel filter

5¡20

1981 SR540E

2. Steering handlebar adjustment By loosening the bolt securing the handlebars, the height of handlebars can be adjusted to suit the rider's preference. After adjustment. be sure to tighten the bolts.

5-7. SKIS A. Inspection Check the ski runner. if worn excessively, replace.

WARNING: - - - - - - - - - - , Tighten the bolts alternately to maintain a parallel gap as illustrated.

(1.5 mm for front and 3.5 mm for rear)

Tightening torque: 1.5 m-kg (11 ft-Ib)

1. Holder 2. Handlebar

5-21

1981 SR540E

CHAPTER 6. ELECTRICAL 6-1.

6-2.

IGNITION SYSTEM ......................................................................................................6-2

A.

Circuit diagram .....................................................................................................6-2

B.

Troubleshooting ...................................................................................................6-2

C.

Ignition timing ......................................................................................................6-3

D.

Spark gap test .......................................................................................................6-4

E.

Ignition coil ............................................................................................................6-5

F.

Spark plug .............................................................................................................6-5

G.

Pulser and charging coils test ............................................................................ 6-6

H.

C.D.I. unit ...............................................................................................................6-7

LIGHTING SYSTEM .....................................................................................................6-7

A.

Circuit diagram .....................................................................................................6-7

B.

Headlight beam adjustment ...............................................................................6-7

C.

Lighting coil test ...................................................................................................6-7

D.

Voltage regulator. .................................................................................................6-9

E.

Oil caution switch ..............................................................................................6-10

1981 SR540E

CHAPTER 6. ELECTRICAL 6-1. IGNITION SYSTEM A. Circuit diagram

~------------------~

®

~--------~

11

111 1. C.D.I. magneto 2. Pulser coil 3. Charging coil

4. C.D.I. unit 5. Main switch 6. Tether switch

7. Engine stop switch 8. Ignition coil 9. Spark plug

B. Troubleshooting No spark is produced or weak.

'---_C_h_e_c_k---,o,f_c_o_n_n_e_c_ti_o_n_s---'I ................. Check lead wire connections or short circuits

~

I

OK

Faulty--------tl Correct.

r_k_t-Ir;I-_s~t~ _I._

'---_S_p_a

~

.. _"'_"_"_"._.._..._.'_"_"'_"_"_"._,,_,,_.s_e_e_6-,- 1- D. "Spa rk gap test"

No spark

Spark-------tl Plug is faulty .

'-------~~------~

OK

~----~~----~

OK

........................... Measure coil resistance.

(See 6-1-G. "Pulser and charging coil test") Fa u Ity --------------.1 Replace .

............................. Measure coil resistance.

(See 6-1-G. "Pulser and charging coil test") Faulty----------+I Replace .

.J. 6·2

1981 SR540E

.......................... Ignition coil test (See 6-1-E. "Ignition coil") Faulty

OK

U" "T~_it- - JI

,--C_._D_.I_.

, Replace.

...................................... see 6-1-H. "C.D.I. unit"

l Faulty

, Replace

The engine starts but will not pick up speed.

Spark plug

1.................................... Clean

or replace (See 6-1-F. "Spark plug")

I

OK

........................... Make continuity test '-----.-----' (See 6-1-G. "Pulser and charging coil test") OK

'--_ _-.-_ _ _ _ _--' .................. (See 6-1-C. "Ignition timing)

'----~--'

...................................... (See 6-1-H. "C.D.I. unit")

'--------------+

Faulty ---------., Replace.

C. Ignition timing 1. Remove the fan case cap.

2. Remove the right side spark plug and screw dial gauge stand into spark plug hole.

Tool name Dial gauge stand

Tool No.

90890-01195

3. Insert dial gauge with needle into stand.

Tool name

Tool No.

Dial gauge

90890-01252

Dial gauge needle

90890-03098

4. Rotate magneto flywheel until piston is at top-dead-center (T.D.C.) Set the zero on dial gauge face to line up exactly with a dial gauge needle.

Tighten set screw on dial gauge stand to secure dial gauge assembly. Rotate flywheel back and forth to be sure that indicator needle does not go past zero.

6-3

\1981 SR540E

5. Starting at T.D.C., rotate flywheel counterclockwise until dial gauge reads approximately 3-1/2 needle revolutions before-top-dead-center (B.T.D.C.).

6. Slowly turn flywheel clockwise until dial gauge reads specified ignition timing.

e. Install the drive fan pulley and starter pulley. (See "2-2-F-2. Cooling fan installation") f. Install the starter assembly. (Refer to "2-2-G. Starter") 8. Remove the dial gauge and stand.Replace the spark plug and fan case cap.

Ignition timing (B.T.D.C.) 1.5 Âą 0.1 mm (0.059 Âą 0.004 in)

Spark plug tightening torque: 2.8 m-kg (20 ft-Ib)

7. Check the marks on flywheel and base for alignment.

If not aligned, adjust ignition timing as follows.

NOTE:------------------------The timing light should be used to check if the marks on the rotor and base are aligned when both are replaced with new ones. The marks should align at any specified timing.

D. Spark gap test The entire ignition system can be checked for misfire and weak spark using the Electro Tester. If the ignition system will fire across a sufficient gap, the engine ignition system can be considered good. If not, proceed with individual component test until the problem is found.

1. Warm up engine thoroughly so that all electrical components are at operating temperature.

2. Stop engine and connect tester as shown.

a. Remove the manual starter assembly. b. Remove the starter pulley and drive fan pulley. (Refer to "2-1-0 Cooling fan") c. Loosen the base set screws and turn the base assembly until mark alignment is achieved.

GEB +

CD 1. Electro-Tester 2. Plug wire from coil 3. Spark plug

d. Tighten base set screw.

Tightening torque: 0.65 m-kg (5 ft-Ib)

3. Start engine and increase spark gap until misfire occurs.

Minimum spark gap: 6 mm (0.24 in)

6-4

1981 SR540E

E. Ignition coil 1. Coil spark gap test a. Remove the ignition coil from frame. b. Connect Electro Tester as shown. c. Connect fully charged battery to tester. d. Turn on spark gap switch and increase gap until misfire occurs.

Minimum spark gap: 6 mm (0.24 in)

-- --

F. Spark plug The life of a spark plug and its discoloring vary according to the habits of the rider. At each periodic inspection. replace burned or fouled plug with suitable one. Suitability may be determined by asking the rider how long and how fast he rides. Recommend a hot. standard. or cold plug type accordingly. It is actually economical to install a new plug often since it will tend to keep the engine in good condition and prevent excessive fuel consu mption.

1. How to "read" spark plug (condition) (The spark plug color samples are at the end of this manual) CD Good The insulator normally has a tan color.

This check should be made after driving the machine over a long distance: otherwise. the correct reading of the spark plug will be impossible. ® Bad (Mixture is too rich or spark plug temperature is low).

If mixture are too rich. the metal shell end will be wet as shown in the photo. acceleration or high-speed performance will be poor. If the spark plug temperature is low. the phenomenon specified in above will not take place. As shown in the photo. the insulator is dark and sooty. @ Bad (Mixture is too lean or spark plug temperature is high.)

The insulator is roughened (lower photo) or burned white (upper photo). and the ground electrode is green due to oxidation. This state of the spark plug

1. Battery

2. 6 mm (0.24 in)

2. Coil winding resistance tests Use a pocket tester or equivalent ohmmeter to determine resistance and continuity of primary and secondary coil windings.

Primary coild resistance

Secondary coil resistance

Hitachi (CM62-20)

0.15H ± 10% at 20°C (68°F)

3.6kH ± 20% at 20°C (68° F)

Toyo Denso (YW-51 )

0.12H ± 10% at 20°C (68° F)

4.0kU ± 20% at 20°C (68°F)

Manufacturer

Primary coil resistance Secondary coil resistance

6-5

1981 SR540E

@

®

@

2. a.

b. Clean the electrodes of carbon and adjust the electrode gap. c. Be sure to use the proper reach plug as a replacement to avoid overheating. fouling or piston damage.

will result in premature ignition or power loss.

Bad (Piston holed or seized) The metal shell end and insulator show signs of overheating. If mixture is too lean. the piston can be holed or the engine may tend to knock. As a result. the spark plug will have occasional aluminum deposits.

Bad (Knocking) Generally. the spark plug will not be greatly affected by the strength of mixtures; so long as the distance travelled is not long. But after long hours of driving. the insulator takes a greyish black color due to aluminum deposits. If so. the engine will fail to deliver full power. and the piston could be holed or seized. As a preventive measure. it is recommended to use a higher octane gasoline. adjust the ignition timing. enrich the mixture or remove the carbon in the cylinder.

Bad (Melting) If the spark plug overheats. electrodes will met away or the piston will be holed.

Inspection Instruct the rider to: Inspect the clean the spark plug every 400 km (250 mi) or 20 hours.

1. Yellow 2. Brown

3. Black 4. Blue

Spark plug type: BR9EV (NGK) Spark plug gap (use wire gap gauge): 0.7 '" 0.8 mm (0.028 '" 0.031 in) Spark plug torque: 2.8 m-kg (20 ft-Ib) G. Pulser and charging coil test Check the resistance between terminals. If resistance is out of specification. coil is broken. Check the coil connections. If the coil connections are good. then the coil is broken inside and it should be replaced.

Charging coil resistance: Black to Brown leads: 350n ± 10% at 20°C (68 0 F) Black to Blue leads: 15.0n ± 10% at 20°C (68 0 F) Pulser coil resistance: Black to White/Red leads: 9.0n ± 10%at20°C(68°F)

5. White/Red 6. Flywheel magneto

6-6

7. Pocket tester 8. Set tester at "RX1" position

1981 SR540E

H. C.D.I. unit In case of ignition failure with all the above system check-ups proving in good order, replace the C.D.I. unit assembly.

~--------~Q------------~ Horizontal line

h

Q

3.0m(10ft)

7.6 m (25 tt)

h

26 mm (1.0 in)

66 mm (2.6 in)

2. Adjustment When necessary, adjust headlight beam by tightening or loosing the four headlight mounting screws.

6-2. LIGHTING SYSTEM A. Circuit diagram

1.

2.

3.

4.

Flywheel magneto Lighting source coil Voltage regulator Headlight

5. Meter light 6. Taillight 7. Brake light

C. Lighting coil test Check the resistance between yellow lead and ground. If resistance is out of specification, coil is broken. Check the coil connections. If the coil connections are good, then the coil is broken inside and it should be replaced.

B. Headlight beam adjustment 1. Inspection Check the headlight beam direction. The high beam must be directed downward at an angle of 1/2 0 to the horizontal line.

Lighting coil resistance: Black to Yellow leads: 0.1911 ¹ 10%/20°C (68 0 F)

6-7

1981 SR540E

1. Yellow 2. Brown

3. Black 4. Blue

5. White/Red 6. Flywheel magneto

7. Pocket tester 8. Set tester at .. RX'" position

D. Voltage regulator

@

1. Instruments required for inspection CD Regulator checker. ÂŽ Two 12V batteries. @ Sub lead wire.

2. Connections Connect two 12V batteries in series using the sublead wires.

Connect the red lead wire (A) (for power) of the regulator checker to the positive side of one of the batteries. and connect the bl'ack lead wire (8) to the negative side of the other battery.

6-8

1981 SR54Q.E:

Connect the red lead wire (C) (for test) of the regulator to the regulator case. and connect the black lead wire (0) to the lead wire of the regulator.

3. Inspection Checking the battery voltage First. set the switches. both right and left. to "12V" "Va LT". If the checker needle points to 20 volts or more. the battery voltage is sufficient.

Thyristor working voltage: 13.8 ± 0.5 volts at 5.000 r/min If the regulator is faulty: The checker needle swings over the black zone. and it will not return to 0 from 20V or more.

E. Oil caution switch The oil caution light comes on when there is little oil in the oil tank. thus warning the rider.

The oil caution circuiut can be checked by squeezing the brake lever.

4. Checking the regulator a. Set the right switch to "REG". If the lamp lights up. there is continuity in the regulator checker. b. Operation test Slowly slide the switch to the right. If the needle quickly swings back to O. the moment that it moves into the black zone of the scale. the working voltage of the thyristor in the regulator is in good condition. and the regulator is also in good condition.

@ ,---I ®

---..,

G

I I I

G/yl

®

IL ___ _

___ ..J

BIR (j)

6-9

1. Flywheel magneto 2. Brake switch

5. Oil level switch

3. Oil caution switch ass·y 4. Diode

7. Oil caution light

6. Brake light

1981 SR540E

moved down to the bottom end of the slider. the tester should read zero. If not. the switch must be replaced.

1. Oil level switch check a. Connect the pocket tester leads to the oil caution switch ass'y lead connector Pocket tester (-) +----+ Green lead Pocket tester ( + ) +----+ Black/Red b. Side the switch float. When the float is

2. Diode check Check the diode as specified using the pocket tester.

Pocket tester connecting point

Lead wire color

(+)

(-)

Red

Black

Black/Red

Green/Yellow

Green/Yellow

Black/Red

Black/Red

Green

----------.- -------------

Replace (element shorted)

0 -------------

------------.---

x

------------- -------------Green

Good

0 ---------------

Black/Red

x

0: Continuity x : Discontinuity

NOTE:------------------------When making this testing. the switch float must be moved down to the bottom end of the slider. (switch ON position)

6-10

0

0

Replace (element opened) x

---------------x

x 0 ------------ ---- -----.-----x 0

1981 SR540E

CHAPTER 7. APPENDIX 7-1.

SPECIAL TOOLS ...........................................................................................................7-2

7-2.

SPECiFiCATIONS .........................................................................................................7-3 A.

General ..................................................................................................................7-3

B.

Engine ....................................................................................................................7-3

C.

Drive and track suspension ................................................................................7-5

D.

Chassis ...................................................................................................................7-5

E.

Electrical ................................................................................................................7-6

F.

Tightening torque .................................................................................................7-7

7-3.

WIRING DIAGRAM .....................................................................................................7-9

7-4.

WIRE AND PIPE ROUTING DIAGRAM .................................................................7-10

1981 SR540E

CHAPTER 7. APPENDIX 7-1. SPECIAL TOOLS 1.

5..

4-b,

....

~

...â&#x20AC;¢.~.

3.

7 No.

Description

Tool No. 90890-03097

1

Dial gauge

2

Dial gauge stand No.2

90890-01195

3

Dial gauge needle (56 mm)

90890-03098

4-a

Flywheel puller attachment

90890-01803

4-b

Flywheel puller attachment

90890-01804

4-c

Flywheel puller screw

90890-01906

4-d

Drive handle

90890-01817

4-e

Flywheel puller body

90890-01848

Rotor holding tool

90890-01235

5 6-a

Primary fixed sheave puller (M 18)

90890-01898

6-b

Primary fixed sheave puller (M20)

90890-01897

6-c

Primary fixed sheave puller attachment

90890-01899

Sheave sub-assembly tool

90890-01858

8

Bushing tool

90890-01883

9

Sheave gauge

90890-01702

10

Pocket tester

90890-03104

11

Electro tester

90890-03021

12

A.C. Regulator checker

90890-03090

13

Sheave holder

90890-01701

14

Eccentric bearing installer

90B90-0 1851

7

" IT

iTSL-90018-81-01 TSL-90018-59-02

14.

TSL-90018-80-00

7-2

1981 SR540E

7-2. SPECIFICATIONS A. General SR540E

Model Model: Model (I.B.M. No.) Frame 1.0. & starting number Engine 1.0. & starting number

SR540E (8l9) 8l9-016101 SA535-016101

Dimension: Overall leng-th Overall width (std) Overall height (w/windshield)

2,610 mm (102.7 in) 1,080 mm (42.5 in) 970 mm (38.2 in)

B. Engine Description: Engine type

Axial fan cooled two-stroke, torque induction, twin cylinders SA535 535 cc (32.65 cu.in) 73 x 64 mm (2.874 x 2.52 in) 6.0: 1 Recoil hand starter C.D.I. "Autolube" oil injection

Engine model Displacement Bme x Stroke Effective compression ratio Starting system Ignition system lubrication system Cylinder head: Combustion chamber volume (with spark plug) Compression chamber type Head gasket thickness x Q'ty

27.5 cc (1.68 cu.in) Dome + Squish 0.5 mm (0.02 in) x 1 pc.

Cylinder: Material Bore size Taper limit Out of round limit

Cast iron sleeves aluminum 73 mm (2.874 in) 0.05 mm (0.0020 in) 0.01 mm (0.0004 in)

Piston: Piston skirt clearance (measuring point)

0.055 ~ 0.060 mm (0.0022 ~ 0.0024 in) (17 mm from piston skirt end) 1st 73.25 mm (2.884 in) 2nd 73.50 mm (2.894 in) 3rd 73.75 mm (2.904 in) 4th 74.00 mm (2.913 in) 4>20 x 56 mm (4)0.787 x 2.20 in)

Piston oversize

Piston pin outside diameter x length Piston ring: Piston ring design (Top) Piston ring design (2nd) Ring end gap (installed)

Keystone Keystone 0.30 ~ 0.50 mm (0.012

Small end bearing: Type

Needle bearing

Big end bearing: Type

Needle bearing

Crankshaft: Crankshaft assembly width (A)

200

7-3

~

0.020 in)

Âą 0.25 mm (7.87 Âą 0.010 in)

1981 SR540E

+0

(

+0

.)

Crankshaft assembly width (F)

60 -0.05 mm 2.362 -0.002

Crankshaft deflection (D)

0.03 mm (0-1) 0.04 mm (0-2) 0.04 mm (0-3) 0.05 mm (0-4) 0.25 ~ 0.75 mm (0.010 ~ 0.030 in) 2.0 mm (0.079 in)

Connecting rod big end side clearance (C) Connecting rod small end deflection (P)

In

-jf-p

Q

I

J

lI~A~" Crank pin outside diameter x length Crank pin type Crank bearing type (left) x q'ty Crank bearing type (Center) x q'ty Crank bearing type (Right) x q'ty Crank oil seal type (left) x q'ty Crank oil seal type (Center) x q'ty Crank oil seal type (Right) x q'ty

1/>24 x 59 mm (1/>0.945 x 2.323 in) Solid shaft assembly type with serration #6306 special x 2 pcs. #6206 special x 2 pcs. #6206 special x 1 pc.

FWJ-3278 9.5 TS x 1 pc. labyrinth seal x 1 pc.

FWJ-3248 10-1 TS x 1 pc.

Cooling fan: Fan belt tension

4 ~ 6 kg/8 mm (8.8 ~ 13.2 Ib/0.31 in)

Carburetor: Type & manufacturer/quantity 1.0. Mark Main jet (M.J.) Main air jet (MAJ.) Power jet (Pw.J.) Power air jet (Pw.A.J.) Slow jet (S.J.) Slow air jet (SAJ.) Pilot screw (P.S.) Starter jet (St.J.)

B044-38/KEIHIN/1 pc.

81900 #150 #180 #150 #170 #92 #100 2-1/4 turns out #160

Float height

15 +2 mm (0.59 +0.08 in)

Idling engine speed

1500 r/min

-3

-0.12

[Main jet setting chart]

~

Altitude

Se.llevel

- 600 m (2000 tt) - 1200 m (4000 It) - 1800 m (6000 It) - 2400 m (8000 It) - 3000 m (10000 tt)

-30°C (-22°F)

-(#155) -#155 -#150 -#145 -#140 -#135

..

-20°C (-4°F)

.. .--

---

--

-

-lOoC (14°F)

O°C (32°F)

#150 #150 #145 #140 #135 #130

7-4

.. · .. ..

. ·.

·

-

lOoc (50°F)

20°C (68°F)

..

_#145 ___

#145 #140 #135

-

· ·

#130

-

#125

·

.

1981 SR540E

Intake reed valve: Type Bending limit Valve lift

V type 0.6 mm (0.024 in) 9.7 mm (0.38 in)

Lubrication: Autolobe pump-Color code Autolube pump-Minimum stroke Autolube pump-Maximum stroke Autolube pump-Reduction ratio Autolube pump-Output Min./200 strokes Autolube pump-Output Max./200 strokes Autolube pump wire free play Oil tank capacity Oil grade

Pink 0.20 ~ 0.25 mm (0.0079 ~ 0.0098 in) 1.65 ~ 1.87 mm (0.0650 ~ 0.0736 in) 1/40 0.95 ~ 1.19 cc (0.0321 ~ 0.0402 oz) 7 .84 ~ 8.89 CG (0.2651 ~ 0.3006 oz) 25 ± 1 mm (0.98 ± 0.04 in) at idle 2.5 Liter (2.6 US.qt) YAMALUBE 2-cycle

C. Drive and track suspension Transmission: Type Drive ratio Engagement rpm Primary spring: Part No. Color code Secondary spring: Part No. Color code Secondary spring pre-load (twist)

V-belt automatic centrifugal engagement 3.5: 1 ~ 1 : 1 3400 ~ 3800 r/min 90501-50500 Red 210" (No.3 hole) 90508-45286 Yellow 180 0 (No.2 hole) +0

+0

.

Sheave distance

270 -3 mm (10.63 -011 In)

Sheave off-set V-belt width and outer line length V-belt wear limit

11 ± 0.5 mm (0.433 ± 0.020 in) 31.6 x 1.099 mm (1.24 x 43.3 in) 26 mm (1.02 in)

Track suspension: Type Damper type Spring color code (Front) Spring color code (Rear) .Slide runner wear limit Track width Track deflection Length on ground Wheel sprocket matenal and number of teeth Stopper band length

No painted 10 mm (0.394 in) 381 mm(15in) 25 ~ 30 mm/l 0 kg (0.98 ~ 1.18 in/22 Ib) 942 mm (37.1 in) Double Polyethylene. 9 teeth 220 mm (8.66 in) (No.1 hole from the bottom)

Secondary drive: Type Reduction ratio Chain pitch x Number of links

Chain (#35K-3) 17/31 (1 : 1.824) 9.525 mm (0.375 in) x 66L

Slide rail suspension Oil and gas damper Red-Green

+ 5

+0.2

.

Free play

10 -2 mm (0.4 -008 In)

Chain housing oil quantity Chain housing oil grade

250 cc (8.5 oz) Gear oil API "GL-3" (SAE #75 or 80)

Brake: Type Brake pad thickness Brake pad wear limit Brake cable "L" distance

Floating disc type 13.5 mm (0.53 in) 9.5 mm (0.37 in) 57 mm (2.24 in) 0.15 mm ~ 0.3 mm (0.006 ~ 0.012 in)

Clearance between lining pad and disc 7-5

1981 SR540E

D. Chassis Frame: Material

Aluminum

Steering system: Caster (ski column) Camber Ski length x width x thickness Ski stance Ski toe-out Steering linkage type Lock to lock angle (Ski)

+ Steel

25° 0° 980 x 120 x 2 mm (~8.6 x 4.7 x 0.08 in) 880 mm (34.6 in) Omm(Oin) Tie-rod Right ski, L: 27.9° R: 33.4° Left ski.

L: 33.4° R: 27.9° Right: 46° Left: 46°

Steering angle Front suspension: Type (YAMAHA T.S. SUSPENSION) Damper type

Coil spring Oil and gas damper

Fuel tank: Capacity Fuel grade

26.6 Liter (7.0 US gal.)

Regular gasoline

E. Electrical Ignition system: Type-flywheel magneto (C.D.I. Type) Model/Manufacturer Voltage Pulser coil resistance Charging coil resistance Charging coil resistance

F3T352/MITSUBISHI 12V 9.0n ± 10% at 20°C (68°F) (White/Red-Black) 350n ± 10% at 20°C (68° F) (Brown-Black) 15.0U ± 10% at 20°C (68° F) (Blue-Black)

Ignition timing: B.T.D.C.

1.5 mm (0.059 in)

Ignition coil: Manufacturer/Model/Quantity Spark gap

HITACHI : TOYO-DENSO CM62-20/1 pc. : YW-51/1 pc.

9 mm (0.4 in)/300 r/min.

11 mm (0.6 in)/3,OOO r/min.' • 0.1 5U ± 10% at 0.12U ± 10% at 20°C (68°F) 20°C (68°F) 3.6kU ± 20% at 4.0kU ± 20% at 20°C (68°F) 20°C (68°F)

:.

Primary winding resistance Secondary winding resistance Diode (Yes or No)

No

•

Spark plug: Type & quality Spark plug gap

NGK BR9EV x 2 pcs.

0.7 ~ 0.8 mm (0.028 ~ 0.031 in)

Spark plug cap: Type Noise suppressor resistance

Resign type with noise suppressor 5kn ± 25% at 20°C (68°F)

C.D.I. unit: Model/Manufacturer

8H4-20/MITSU BISH I

Lighting system: Lighting output Lighting coil resistance Headlight type Bulb wattage/q'ty Tail/Brake light wattage

12V-l00W 0.19n ± 10% at 20°C (68° F) (Yellow-Black) Halogen light 12V-60/55W x 1 pc.

12V-8W/23W 7-6

.

1981 SR540E

A.C. regulator: Model/Manufacturer Voltage

TRIZ-24B HITACH or SB5 16B TOSHIBA 13.B ± 0.5V

F. Tightening torque Part to be tightened

Thread size

[Engine) Spark plug Cylinder head Cylinder Flywheel magneto Crankcase upper and lower

M14Pl.25 MB Pl.25 MB Pl.25 M16Pl.0 MB Pl.25

Tightening sequence

M6

Pl.0

Tightening torque

Remarks

2.B m-kg (20 ft-Ib) 2.5 m-kg) lB ft-Ib) 2.5 m-kg (lB ft-Ib) 7.3 m-kg (53 ft-Ib) First: 1.0 m-kg (7 ft-Ib) Final: 2.0 m-kg (15 ft-Ib) First: 0.5 m-kg (3.5 ft-Ib) Final: 1.0 m-kg (7 ft-Ib)

;----:------',-----1/-

ft6_~~2 ~~_$-5

1°

4+

. "'0. __ i9 I

11

Ring weight and stay Flywheel magneto and stay Fan shaft and pulley 2

M6 Pl.0 MB Pl.O M16Pl.0

1.0 m-kg (7.2 ft-Ib) 1.5 m-kg (1 O.B ft-Ib) 4.3 m-kg (31.1 ft-Ib)

Starter pulley Crankcase and engine bracket

MB MB

2.3 m-kg (16.5 ft-Ib) 2.3 m-kg (16.5 ft-Ib)

[Drive and track suspension) Primary sliding sheave and cap Installation of primary sheve

Installation of secondary sheave Bearing housing Brake caliper and housing chain Installation of drive chain sprocket Installation of driven chain sprocket Chain housing and frame Installation of front axle L. H. Front axle housing and frame Wheel sprocket and front axle Front pivot shaft Rear pivot shaft Rear axle Sliding runner [Chassis) Engine mounting bolt Steering column and gate Steering gate Steering relay rod adjusting nut Steering lower bracket Installation of steering column 1.2

Pl.25 Pl.25

M6 Pl.O UNF 1/2"

M14Pl.5 MB Pl.25 M10P1.25 M14Pl.5 M10P1.25 MB Pl.25 M22 Pl.0 MB Pl.25 M6 Pl.0 M10P1.25 Ml0 P l.25 M12 Pl.25 M6 Pl.O M10P1.25 M8 Pl.25 MB Pl.25 Ml0Pl.25 MB Pl.25 MB Pl.25

7-7

1.1 m-kg (B ft-Ib) Initial: 12 m-kg (B7 ft-Ib) Loosen once and retighten: 6.5 m-kg (47 ft-Ib) 6.4 m-kg (46 ft-Ib) 2.3 m-kg (16.5 ft-Ib) 4.B m-kg (35 ft-Ib) 6.0 m-kg (43.5 ft-Ib) 4.B m-kg (35 ft-Ib) 2.3 m-kg (16.5 ft-Ib) B.5 m-kg (61.5 ft-Ib) 2.3 m-kg (16.5 ft-Ib) 0.55 m-kg (4 ft-Ib) 6.4 m-kg (46 ft-Ib) 6.4 m-kg (46 ft-Ib) B.O m-kg (5B ft-Ib) 0.45 m-kg (3.3 ft-Ib) 5.2 m-kg 2.3 m-kg 1.4 m-kg 4.7 m-kg 2.3 m-kg 1.45 m-kg

(37.6 ft-Ib) (16.5 ft-Ib) (10 ft-Ib) (34 ft-Ib) (16.5 ft-Ib) (10.5 ft-Ib)

Use Neji lock (Adhesive) Use Neji lock (Adhesive)

Use motor oil

Use lock washer

Use lock washer

1981 SR540E

Steering relay ass'y Front shock absorber and bracket Bracket 1. 2 set bolt Front arm Ski installation

M10Pl.25 M8 P1.25 M6 Pl.0 Ml0Pl.25 Ml0 P1.25

7-8

4.7 2.1 0.2 1.6 4.3

m-kg m-kg m-kg m-kg m-kg

(34 ft-Ib) (15.2 ft-Ib) (1.4 ft-Ib) (11.6 ft-Ib) (31. ; ft-Ib)

Use cotter pin

..., I

W

I

I

Speedometer light (12V3.4W)

Oil caution light (12V3.4W)

Headlight (12V 60W/55W)

01

..

..

L

G/Y B

I" :

LG Y

L

o

B

o

1'~

BIW

Y B Ignition coil

II

~

.---. - - I-- - - I--

'-1--'-----0, L

Voltaglf regulator

011 level switch

,J L

Br L

0

Br~

......

?

~ I:~ ~ l:

~

Spark plug

I

B

C.D.I. unit

(,

-cr -=

.~ ~

-=

C.D.I. magneto Color code L. ............ Blue y ............. yellow Orange G ............ Green Br ........... Brown Gy .......... Gray

o ............

R............. Red B ............ Black G/y ........ Green/yeliow B/R ........ Black/Red B/W ....... Black/White W/R ....... White/Red

.....

<0 00

WIRE AND PIPE ROUTING DIAGRAM Meter Dssembly

Engine stop switch ~---~-Tail light lead wire

Head light dimmer sWItch

'-~~~

;-----------

Band

/wi";:-harness "/~~--

/

Main'iwitch

-------

Brake cable

C:3:/~~: -

T.achometer cable

lIJl.-t-----.--

Speedome~ cable

h~~

I

-

Holder bearing

Oil tank breather pipe ,

I

Intake silencer (Upper)

...-1--------- - - .-----

J

Speedometer cable

Frame Intake silencer (Lower)

{} @r---..

Details of oil pipe routing

/

~c~;; Wire harness

..~~... (/J.lLlfO -~~\} [TnT. ~{~.I~ \ L\\JcI~ff~~·; ( _J

I~

/ """'00 coli /

ig)'

/

~__

~

'0,adll,h<I"dwl"

-~---SL ~

_y

~

Head I'9tH vnit

Meter gear ass'y

Engme stop switch lead Main switch lead Tai! Ilgl'lt lead

/

/

MeIer assembly lead

~ Head l\ghtbeam sWitch lead ~ht'w"'hl"d Tether SWItch I~ad

Fuel pipe

Olile-ve! gauge

Fuel tank breather pipe

Fuel pump

carburetor

Fuel deJlvery plpe

Details of wire harness routing

Details of fuel pipe routing

SR540E RACING TIPS Testing in Alaska has yielded the following pro-stock racing specifications and adjustments for the SR540E. Yamaha has found that these recommendations produce the best performance under specific test conditions. Different local conditions, however, may require different settings. Use these recommendations as a guide, not hard and fast rules. Always tune your machine to suit the particular conditions of each race.

ENGINE AND CLUTCH See technical bulletin S80-012 for standard specifications.

CARBURETOR TUNING The standard 150 main jet is too rich (especially for the left-side cylinder) even at sea level.

Reduce the main jet size to get good plug color at full throttle. As you reduce the main jet, the right-side cylinder will not change, but the left-side cylinder will become more and more lean until it matches the temperature of the right-side cylinder.

CLUTCH TUNING 1. Primary Spring Standard

First Option

Second Option

90501-50500-00 Red 25 x 1.4 kg/mm

90501-55456-00 Silver-White 30 x 2.0 kg/mm

9050 1-55241-00 Red-Pink 35 x 1.75 kg/mm

2. Clutch Weights Select the rivet quantity and location to maintain a 7100 rv 7200 shift rpm.

3. Secondary Settings Hole #3 (210°)

or Stretch the spring to 8.5 inches free length. Assemble the clutch with 90° (hole #3) of twist preload. This specification improves the backshifting characteristics of the machine.

Restretch the spring when its free length decreases to 7.5 inches or less.

SUSPENSION 1. Install tunnel protectors (888-21978-00-001. Since the SR540E has a longer track, the standard protectors are too short. Therefore, mount the protectors as far forward as possible to protect the steel portion of the frame.

2. Countersink the suspension pivot shafts for fast installation; install the fender washers under the slide suspension mounting bolts to protect the frame.

COUNTERSINK THE SUSPENSION SHAFTS

INSTALL FENDER WASHERS

3. Install an additional rear idler wheel on the rear axle as shown in the illustration. This additional wheel will reduce the possibility of the track derailing.

SPACERS

4. Install an additional hose clamp onto each track drive sprocket. The clamps should be mounted against one another. Check the clamps before each race; they should be tight.

SUSPENSION SETTINGS A. Smooth Course (Lake Racing) 1. Shorten the slide rail limiter straps so the suspension has the indicated amount of travel. You will have to drill a new hole in each strap.

-----

--.~-----.---------.

-==-------- ---_._-------- -.-

---- --

--~-"

.

2

---------

-------------

~'-~

2. Install a slide suspension limiter strap to the T. S. S. steering link bolts to limit travel to 95mm (3.7 in). Set the nitrogen pressure to 7.0 kg/cm2 (100 psi).

3. Select a rear shock absorber from the Optional Parts Summary to suit the local conditions.

4. Install the 1980 SR-V front slide-rail shock (BK4-47481-oo) if desired.

5. For W. S. R. F. lake racing, install the front stabilizer kit and select a softer T. S. S. spring from the Optional Parts Summary.

SR-V Front Stabilizer Kit BL9-WOO51-00-oo SRX440E Front Stabilizer Kit BM6-W0051-oo-oo B. Rough Course (Cross Country) 1. Use full travel front and rear. Adjust the slide rail limiter straps for the desired steering characteristics.

2. Use the front stabilizer kit if desired.

3. Select a rear shock absorber frQm the Optional Parts Summary. We recommend the 1980 SS440/SR540 shock (BK4-47480-oo-00).

4. Install the 19BO SR-V front slide shock absorber (BK4-47489-oo-00) if desired.

TRACK STUDS AND CARBIDES 1. Break in the track and adjust it to specification before each race.

2. Stud the track with carbide penetrators where shown in the illustration. Burn the holes in the track; do not drill them .

• D• 0 D 0 0• 0 0• D 0• D D• D D• D D• 0 •

•

•

•

•

•

,

•

•

D 0 D 0 D D D D D D 0 D 0 D D 0

•

•

•

•

3

•

•

•

•

3. Install carbides on the Kalamazoo KXC 925 host bar where shown in the illustration. a. Lake Racing (no snow)

SKI MOUNTING BOLT

".

3 FLATS

'-..,

I

I,

I

4 FLATS

l.to I' I 'f I s I .. I 7 111 I ,

I

I

I

I

9 CARBIDES approx.

approx.

45/8"

5 1/3"

b. Cross Country Racing

SKI MOUNTING BOLT 4 FLATS '-.. ,

,

I

,

"".

I I

I -approx.- l

1.... 1., I'l'l

s

I I" I ~

7 CARBIDES

5 3/8"

5 FLATS I

I

I

I

f -approx.----t 6 5/8"

CHASSIS 1. Install SRX ski tip protectors (SM6-23747-00-00), radiator hose and cable ties, or other suitable ski loop padding to satisfy W.S.R.F. recommendations.

2. Disconnect the handlebar kill switch to eliminate potential mishaps.

3. Install the accessory high windshield (ABA-SK496-00-00) for comfort in cold weather racing.

4. Tie the rear snow flap to the frame to satisfy W.S.R.F. rules (see the rule book).

5. Reinforce the rear tunnel where shown in the illustration.

REINFORCE

4

6. Install a motorcycle-type brake lever with a large free-play adjusting screw to facilitate adjustment during the race. The brake light must function.

7. Drill the hyfax in the pattern shown below. Use a 3/16 inch drill, and drill the holes 4mm (0.15 in) deep.

o

o

o

o

3/16"

O~

0

0

O~

5

J9 3/8"

00

0

00

SNOWMOBILE TOOL LIST PART NUMBER

DESCRIPTION

DEALER COST

TLS-9091 0-47-01 *

Sheave Align Gauge

$ 10.20

TLS-9091 0-47-02

Sheave Align Gauge

15.95

TLS-9091 0-47-03 * *

Sheave

TLS-9091 0-48-00

TSS Strut Holder

TLS-90018-59-02

YP Primary Sheave Puller

12.45

TLS-90018-81-01

ST Primary Sheave Puller

12.45

TLS-90018-80-00

Primary Sheave Holder

19.95

908-90018-83-00

Puller, Bushing

8.13

TLS-9091 0-45-00

Track Clip Tool

43.95

TLU-90901-05-20

Flywheel Puller

30.67

TLM-9091 0-60-00

Nitrogen Charging System

TLM-90910-63-00

Carry Bracket For Nitrogen Charging System

TLM-90011-53-01

Injector Needle

TLS-9091 0-60-00

Clutch Subassembly Too!

14.28

TLU-9091 0-35-00

Vacuum Press Test Kit

72.50

TLU-9091 0-22-00

COl Tester Kit

67.95

~istance

Gauge

5.95 5.95

148.00 14.95 6.39

* Updated Tool Now Available * *Tool Updates TLS-90910-47-01

6

PERFORMANCE SUSPENSION TUNING REAR MAIN SPRING AND DAMPER ASSEMBLY

These charts are to be used as a guide. All settings must be checked under actual running conditions.

DAMPER DAMPER TENSION COMPRESSION RATE RATE

SPRING PART NUMBER

SPRING PRELOAD

SPRING RATE

8K4-47480-00-00

33.1 kg

1.10

T 65

C55

SR540D,SS440D

8K2-47480-00-00

23.8 kg

1.58

T 95

C 85

SRX440D

8L8-47480-00-00

12.0 kg

1.2 - 1.6

T65

C55

SRX440E, SS444E,SR540E

FIRST USAGE

NOTE: The lowest preload and damper compression rate allows the most weight transfer and best acceleration.

REAR MAIN SPRING PRELOAD ADJUSTMENT LOWEST PRELOAD <IIIIC ...- - - - - - - - - - - - -... _~ HIGHEST PRELOAD

STD. SEnlNG NOTE: The lowest preload allows the most weight transfer and best acceleration.

The highest preload is most resistant to bottoming.

7

PERFORMANCE SUSPENSION TUNING REAR SUSPENSION HAIR PIN SPRING

SPRING PART NUMBER

SPRING PRELOAD

SPRING RATE

SPRING COLOR

FIRST USAGE

90508-99479-00 90508-99480-00

12.8 kg

435.8 kg mm/deg.

Yellow

SS440D Retrofit Spring

90508-95476-00 905O8-954n-OO

15.9 kg

358.1 kg mm/deg.

Pink

SR540D Retrofit Spring

90508-85471-00 90508-85472-00

8.5 kg

232.7 kg mm/deg;

Brown

SS440E Standard

90508-99482-00 90508-99483-00

10;0 kg

437.5 kg mm/deg.

Red-Green

SR540E SRX440E Standard

90508-90409-00 90508-90408-00

NA

302.9 kg mm/deg.

Orange

SRX440D SR540D

90508-80410-00 90508-80411-00

NA

191.2 kg mm/deg.

Blue

SS440D

NA

=Information Not Available

8

PERFORMANCE SUSPENSION TUNING

The fewer number of wheels that can be used without Hyfax wear, the greater the acceleration and top speed.

CONDITION #3 ICE OR

SOFT SNOW

CONDITION #2 HARD PACKED OR LlnLE SNOW

No Hyfax Wear less Performance

less Hyfax Wear More Performance

less Hyfax Wear More Performance

ACCESSORY WHEEL PLACEMENT

CONDITION #1

~i~O

"-

" "-

23_ m---=:..

) ~

)

,

,

~

NO SNOW

)

~

~

.0

-

~

No Hyfax Wear More Performance

NOTE: Wheels #1 and #3 come in the crate.

9

f

More Hyfax Wear less Performance

,, More Hyfax Wear less Performance

PERFORMANCE SUSPENSION TUNING TSS SPRINGS 200 175

-C; ~

I II

() ~

2 z

o

iii

fn

III ~

A.

~

()

STRUT TRAVEL (MM)

,

SPRING PART NUMBER

COLOR

90501-75612-00

Red

Hard

1.6

SRX440E at SR540E

BlO-00000-10-00

Blue

Medium

1.0 -1.6

Accessory

BlO-OOOOO-OO-OO

White

Medium Soft

1.01.4

Accessory

90501-70584-00

No Color

Soft

0.8 -1.2

SR540D

RATE

FEELING

i

ORIGINAL APPLICATION

TSS PRELOAD NOTE: TSS preload is set by adjusting the nitrogen pressure In the shock absorber.

TSS

NITROGEN PRESSURE

Max.

284lbs.

Std.

2131bs.

Min.

185lbs.

10

PERFORMANCE SUSPENSION TUNING

FRONT STOPPER BAND

#1

C

A

#5~----~.-----~~----~------~-------e~----~

..

CII

z

#4

C

I11:III III

A. A.

e

#3

In

..

I11:III

C

III

D

#2

#1

B

~----~.-------+-------+--------

The Indicated settings provide: A. Best straight line acceleration and top speed; B. Most positive steering; C. Lowest center of gravity; D. Maximum suspension travel.

Stopper band standard position.

X Un useable combination; shock will top out.

*

11

PRIMARY SPRINGS (Listed In Order of Spring Rates) PART NUMBER

SPRING RATE

9050.1-45534-0.0.

1.0.0.

9050.1-50.50.0.-0.0.

WIRE

OUTSIDE

COLOR

DIA.

DIA.

25

Blu-Grn

4.5

55

4.68

86.5

EX44o.D

1.40.

25

Red

5.0.

55

5.0.7

79.4

ET34o.D

90501-50.543-0.0.

1.40.

20.

Grn-Grn

5.0.

55

5.57

75.8

EC54o.

9050.1-50.351-0.0.

1.40.

40.

Yel-Grn

5.0.

54

5.30.

90.1

GPX-G 50.0.0. rpm

PRELOAD

NUMBER TURNS

FREE LENGTH

FIRST USEAGE

N

9050.1-55230.-0.0.

1.50.

65

Red-SII

5.5

54.5

6.50.

10.4.8

9050.1-50.622-0.0.

1.50.

30.

Yel-Pnk

5.0.

55

4.83

81.5

SR54o.E

9050.1-50447-0.0.

1.75

30.

Pnk-Wht

5.0.

55

4.40.

78.6

EX44o.A

9050.1-55343-0.0.

1.75

30.

Red-Blu

5.5

55

5.80.

78.6

SRX Opt. 40.0.0. rpm

90.50.1-55241-0.0.

1.75

35

Red-Pnk

5.5

55

5.80.

81.5

GPX338/433F Std.

9050.1-55403-0.0.

1.75

40.

Yel-Wht

5.5

54.5

5.75

84.4

EX44o.

9050.1-55225-0.0.

1.75

45

Red-Grn

5.5

55

5.80.

87.2

Tuning Part

90.501-55404-0.0.

1.75

55

Grn-Pnk

5.5

55

5.80.

92.9

Tuning Part

90.50.1-55419-0.0.

1.80.

42

Brn-Wht

5.5

55

5.50

84.8

SRX34o. 50.0.0. rpm

9050.1-5540.4-0.0.

1.80.

49

Org-Wht

5.5

55

5.50.

88.2

SRX44o. 50.0.0. rpm

9050.1-55456-0.0.

2.0.0.

30.

SiI-Wht

5.5

55

5.50.

77.3

SRX44o.A Std.

GPX433F GYT Kit

- _..

--

(Continued)

(Continued)

PRIMARY SPRINGS (Listed In Order of Spring Rates)

w

PART NUMBER

SPRING RATE

90501-55487-00

2.00

90501-55242-00

WIRE

OUTSIDE

COLOR

DIA.

DIA.

NUMBER TURNS

50

Red-Org

5.5

54.5

5.0

93.0

SRX440A Modified

2.00

60

Red-Org

5.5

55

5.40

91.5

GPX338F GYT Kit

90501-55356-00

2.00

64

Blu-Sil

5.5

55

5.40

93.5

GPXG GYT Kit

90501-50396-00

2.00

20

Grn-Wht

5.0

55

4.10

71.5

SRX340 Std.

90501-55345-00

2.05

20

Red-Red

5.5

54.5

5.30

71.3

GPXG Std.

90501-55397-00

2.22

24.5

Red-Wht

5.5

55

4.50

72.5

SRX440 Std.

90501-55388-00

2.40

40

Blu-Wht

5.5

54.5

4.90

78.2

EX340

90501-55485-00

2.50

30

Brn-Wht

5.5

55

4.50

73.5

SRX440A Improved

90501-55559-00

3.00

20

Blu

5.5

55

4.60

68.2

ET250D

PRELOAD

FREE LENGTH

FIRST USEAGE

SECONDARY SPRING CHART SPRING CONSTANT

NO.

PART NUMBER

kg/mm

TURNS'

COIL DIA.

WIRE DIA.

FREE LENGTH

90508-45301-00 90508-45287-00 90508-45286-00

4.86 4.32 4.86

8.0 9.05 8.05

64.5 64.5 64.5

4.5 4.5 4.5

120 120 85

Silver Blue Yellow

90508-40341-00 90508-40080-00

4.86 3.19

5.05 9.9

64.5 50.0

4.0 4.0

85 105

White None

COLOR

USED ON EX440 EX340, A, B SRX340,SRX440, A, B,C, 0, E, SR540D, E, EX440, A, B, C, 0, E, SS440D, E, EXCEL-V, EC540D SRX440, A ET250A, B, C, 0, E ET340B, C, 0, ET340EC ET30OC, 0, E

SPRING PULL CHART Hole Number Degrees Preload (TWist) Silver - Lbs. Pull Blue - Lbs. Pull Yellow - Lbs. Pull White - Lbs. Pull All ET Series

2 60 0

3 90 0

1/2

3/4

8 6 7 6

11 9 10 9

4 1200 1 14 11 12 11

10 Lbs. Pull@160 0 Preload (Twist)

Refer to service data for additional information on proper settings

1 1500

2 1800

3 210 0

1-1/4

1-1/2

1-3/4

16 13 15 14

19 16 18 17

22 19

'<t

CONTENTS I

NEW SERVICE PROCEDURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

1. V-BELT CLUTCH ........................................

2. FRONT AXLE ...........................................

3. FUEL TANK ............................................

4. BELLY PAN LID .........................................

5. PULSER AND CHARGING COIL TEST .......................

6. LIGHTING COIL TEST ....................................

1 1 15 16 17 18 18

II SPECiFiCATIONS ........................................... 19

I. NEW SERVICE PROCEDURE 1. V-BELT CLUTCH NOTE: _________________________

Sheave gauge: YS-91047 (U.S.A.) 90890-01702 2. Check the distance.

The following items under "4-1. Drive" in the SR540E Service Manual will be changed as described below: A. Sheave adjustment B. Primary sheave C. V-belt D. Secondary sheave

sheave

center-to-center

A. SHEAVE ALIGNMENT

1. Sheave distance 270 ~ mm

g

(10.6

~g.11

3. If the center-to-center distance or offset is not within the specification, adjust it in the following manner: 4. Loosen the four engine-mounting bolts.

By moving the engine back and forth, adjust the sheave distance so that the center-to-center distance between the primary sheave mounting bolt and secondary sheave mounting bolt is equal to the sheave gauge setting spefied above.

5. Adjust the thickness of shims on both ends of the secondary sheave so that the distance (offset) between the primary fixed sheave and secondary sliding sheave is equal to the sheave gauge.

6. Repeat steps 4 and 5 above until the sheave distance and sheave offset are adjusted correctly.

2. Sheave off-set 11 Âą 0.5 mm (0.43 Âą 0.02 in)

in)

1. Using the sheave gauge, check the sheave offset. If the gauge does not contact the primary and secondary sheaves at the four indicated points, the sheave offset is incorrect.

-1-

NOTE: ________________________ Select proper shims to be used at A and B. The total clearance at A and B should be 1.0 mm (0.04 in) or less.

90201-225A4 90201-222FO

~~~~~~~~~~~~~~~ 90201-252F 1

7. Tighten the engine mounting nuts while taking care not to move the engine.

Tightening torque: 52 Nm (5.2 m¡ kg, 37.6 ft¡lb)

a

B. CLUTCH TUNING

machine passes point 200 - 300 m (650 1000 ft) from the starting position after the

The clutch may require tuning depending upon the area of operation and the desired handling characteristics. The clutch can be turned by changing engagement & shifting rpm.

Clutch engagement rpm is defined as the engine speed where the machine first begins to move from a complete stop.

Shifting rpm is the engine speed when the

machine has been started at full-throttle from a dead stop.

Normally, when a machine reaches shift rpm, the vehicle speed Increases but the engine speed remains nearly constant. Under unfavorable conditions, however (wet snow, icy snow, hills, or rough terrain), engine speed can decrease after the engine has reached shifting rpm.

Engine rpm Engine rpm

t

t Clutch shifint rpm

Clutch shifting rpm

Clutch engagement rpm

Clutch engagement rpm Starting position

Travelled distance

200 - 300 mm (650 -1000 ft)

Starting position

Good Condition

200 - 300 mm (650 -1000 ft)

Bad Condition

-2-

-

r-------------,r-Travelled distance

1. Clutch setting data a. Standard specification S.t.d. SPEC

High altitude spec

Engagement

r.p.m.

3600± 200

+-

Shifting

r.p.m.

7000 ± 200

+-

90501-55672

90501-50500

36 kg

25 kg

2.1 kg/mm

1.4 kg/mm

Color

GREEN - ORANGE

RED

Q'ty

2 p.c.s.

+-

90201-327E3 (3.2 t) 90201-32710 (1.6 t)

+-

0

+-

Parts No. Set weight

.

Primary spring Spring constant

Spider shim Part No. Primary spring shim

Q'ty Mark

.

8R6

8R9

Part No.

8R6-17633-00

8 R9-17633-00

Weight

Q'ty

.

2 p.c.s.

1 pc (No.1 Hole)

Parts No.

90261-06015

90261 -06016

Parts No.

90508-45508

+-

90°

+-

Weight rivet

Twist angle Secondary spring Spring hole No.

No.3

Color

t

+-

GREEN

+-

NOTE: ____________________________________________________________

The "Highland spec" applies to operation at an altitude of more than 1,500 meters (4,500 feet). b. How to change clutch engagement rpms and clutch shifting rpms

~ Primary spring shim

Clutch engagement r.p.m.

Clutch shifting r.p.m.

Decreasing

Increasing

Decreasing

Increasing

Lessen number of shims

Increase number of shims

-

-

Spring constant

-

-

Decrease

Increase

Preload

Decrease

Increase

-

-

Increase

Decrease

Increase

Decrease

Torsion spring constant

-

-

Decrease

Increase

Twist angle

-

-

Smaller wind

Greater wind

Primary spring

Centrifugal force of weight

Secondary spring

-3-

2.

Primary clutch engagement rpm setting The factors which change the clutch engagement rpm are the primary spring shim, primary spring preload, and centrifugal force of the weights as shown in 1-b. Therefore, the clutch engagement rpm can be adjusted by replacing the primary spring shim, the primary spring itself or the primary weight rivets.

Standard clutch shifting rpm: 6800 ~ 7200

Clutch shifting rpm for highland: 6800 ~ 7200

a.

Secondary spring setting

1) Secondary spring position The spring seat is provided with four holes, Nos. 1 to 4, so that the secondary spring position can be changed as required.

Standard clutch engagement rpm: 3400 ~ 3800

Clutch engagement rpm for highland: 3400 ~ 3800

a. Primary weight setting By changing the position and quantity of primary weight rivets, the thrust of the weights is changed, and thus the engine rpm at which the clutch is shifted is also changed. (As a result, the engine rpm at which the clutch is engaged is changed.)

NOTE: __________________________ The position of rivets for the three weights must be the same.

1. Spring seat

2) Secondary spring tension The secondary spring tension can be changed by moving the spring position from the free position in order to reset the clutch shifting rpm as required. The four holes are spaced at intervals of 30° .

1) Removal of rivets Drive out in the manner as illustrated.

Secondary spring position

Spring wind

No.1

30°,150°,270°

No.2

60°,180°

No.3

90°,210°

No.4

0°,120°,240°

Winding the spring more (i.e., from 30° to 60°) will increase the clutch shifting

2) Clinching of rivets After driving in the rivets, file down the rivet heads so they are flush with weight surfaces.

3. Secondary clutch shifting rpm setting The secondary clutch must be turned to match snow and weather conditions.

Tuning the clutch keeps the engine operating in the proper rpm range.

rpm and vise versa. Snow conditions will also require a change of the spring tension in order to attain the standard shifting rpm. The spring tension must be greater on wet snow than on packed snow. Less tension is needed on icy snow.

-4-

3) Secondary spring setting The secondary spring settings are classified into two types as shown below.

Select a proper setting according to operating conditions. (For the setting procedure, refer to "E. Secondary Sheave.")

Std. secondary spring: PIN: 90508-45508 Color code: Green Std. secondary spring position: No.3 Std. secondary spring twist: 90°

Lake surface

Trail and tour

Course

Position of spring seat

Twist

Position of spring seat

Twist

No.2

60°

No.2

60°

Packed snow

Std.

Std.

Std.

Std.

Wet snow

Std.

Std.

Std.

Std.

Setting factor Ice snow

C. V-BELT

c. Measure the length of the V-belt. It should be within specification, if not, replace the belt.

1. Removal a. Turn the secondary sliding sheave clockwise and push it towards the chain case. b. While holding the sliding sheave in this compressed position, remove the V-belt from the secondary sheave, then from the primary.

2. Inspection a. Visually inspect the V-belt for signs of damage. Replace the belt if it is damaged. b. Measure the width of the V-belt. If the belt is worn beyond the wear limit, replace it.

Part No.

Length of V-Belt

SF2-17641-00

1,099 mm (42.S in)

Q)

Wear limit: 26 mm (1.02 in) 1. V-belt length

\ \

I I

\ \ \

I

\

\ \ \ \ \

I I I I I

I

1. New: 31.5 mm (1.24 in) 2. Wear limit: 26 mm (1.02 in)

-5-

0_ PRIMARY SHEAVE

Apply Three Bon d No . 1305 to the top four threads.

Steel shim Weight

Plastic washer

Sliding sheave

Roller pin

Spider

Washer

CAUTION: Always use a self-locking bolt.

Self-locking bolts must never be reused.

Tightening torque: 54 ftolb) 7.5 Nm (0.75 m-kg, .

Sheave cap

Sheave cap bolt

Tightening torque: 362 tt-Ib) 500 Nm (50 m-kg,

Slider

NOTE:

â&#x20AC;¢X

Tightening torque: e First tighten the bolt to a torqu f A then loosen it. bolt to a final torque of

~eti~hten

Oiling Point No oiling or greasing is allowed.

!.: B:

120 Nm (12 m-kg, 87 ft-Ib) 58 Nm (5.8 m-kg, 47 tt-Ib)

-6-

Tightening torque: 11 ft-Ib) 15 Nm (1.5 m-kg,

1. Removal a. Remove the drive guard, and remove the V-belt. b. Hold the fixed sheave with the primary sheave holder and remove the clutch bolt. Drive the primary sheave off the crankshaft with the primary sheave puller.

Tightening torque: 120 Nm (12 m路kg, 87 ft路lb)

Primary sheave holder: YS-01880 (U.S.A.) 90890-01701 Primary sheave puller: YS-01882 (U.S.A.) 90890-01890

.

,

1. Yamaha spider wrench YS-28890 90890-01711

NOTE: ________________________ Thoroughly clean the tapered portions of the primary sheave and tool (1).

2) Install the tool (2) onto the spider and loosen the spider.

Loosening torque: 500 '" 1,000 N m (50'" 100 m路 kg, 360'" 730 ft路lb)

1. Sheave holder

2. Sheave puller

2. a. b. c.

Disassembly Loosen the six sheave cap bolts Remove the three sliders.

Loosen the six weight pin securing bolts and remove the weights. d. Loosen the six collar pin securing bolts and remove the collars. e. Disassembling the spider, sliding sheave, and bushing (large) WARNING:

NOTE: _______________________ For this operation, the special tools and . Three Bond No. 1305 (required for spider and fixed sheave assembly) are necessary.

If these are unavailable, avoid disassembling.

To loosen the spider, high torque is required and therefore, make sure the primary sheave, vise, and tools are tightely secured also take care not to crack the spider.

1) Secure the primary sheave assembly to the tool (1) gripped in a vise, using the primary sheave bolt.

3) Remove the primary sheave bolt, and using the primary sheave puller, remove the primary sheave assembly from the tool (1).

Yamaha spider wrench: 90890-01711 YS-28890 (U.S.A.)

-7-

Primary sheave puller: 90890~01898 YS-01882 (U.S.A.)

~ 3. Inspection a. Inspect the tapered ends of the crankshaft and the primary fixed sheave for scraches. If either is severely scratched, replace it. If scratches are minor, burnish the component with emery cloth. b. Check the primary sheave cap bushing and the sliding sheave bushing for wear.

If worn beyond tolerance, replace the bushing.

Use the bushing tool if a bushing is difficult to remove.

Bushing tool: 90890-01713

Bushing clearance, limit Small bushing

Large bushing

Inside

0.25 mm (0.01 in)

0.25 mm (0.01 in)

Outside

0.25 mm (0.01 in)

0.25 mm (0.01 in)

c. Weights Check the bushing bore inside diameter of each weight and its contact surface with the collar. If worn more than limits, replace them with new ones.

Wear limit

Bushing bore diameter (d) 10.20 mm (0.40 in)

Contact surface with collar

1. Bushing tool

-8-

Contact surface with collar A

B

0.5mm (0.021 in)

1.0mm (0.04 in)

B

d. Roller Check the inside diameter of the roller bushing, then check the contact surface of the roller and the weight. If either surface is worn unevenly or more than acceptable limits, replace them.

Wear limit

Bushing bore diameter (d)

Contact surface with weight (D)

10.3 mm (0.41 in)

15.0 mm (0.59 in) 1. Wear limit

g. Spider Check the contact surface of the spider with the slider. If it is worn more than limits or cracked, replace it with a new one.

Contact surface with weight Uneven wear

d

Wear limit: 28.5 mm (1.12 in)

If the outer surface of the roller is worn unevenly, the roller is probably seized to the pin. Be sure to check the roller pin. e. Weight pins and roller pins Check both weight and roller pins. If metal dust collects on pins, remove it using sandpaper (# 800 - # 1000).

If the chrome-plated surface of the pin scales off, replace the pin with a new one. f. Slider Install the slider onto the sliding sheave, and check for wear on its contact surface with the spider. If worn more than limits, replace the slider. Also if it is cracked, it should be replaced.

1. Wear limit

h. Primary spring Check the primary spring for damage or fatique, and replace it as required.

4. Assembly a. Install the large bushing into the sliding sheave. Using the weight pin, install the weight, washers, and steel shim in the sliding sheave.

Weight Plastic washer

Wear limit: 30.5 mm (1.20 in)

Sliding sheave

-9-

NOTE: _ _ _ _ _ _ _ _ _ _ _ __ Apply Three Bond No. 1305 to:

The weight should be adjusted so that it has no thrust play. If any Fe-washer is added, it should be installed in the position indicated by the arrow mark.

No. of standard steel shim: 1 pc.

4 threads

I·

Weight pin tightening torqu.e: 75 Nm (0.75 m· kg, 5.4 ft·lb)

1. Three Bond should be applied only to the area apecified. Never apply to the outer surface of the bushing (large) or other areas.

2. Do not use the clutch until the Three Bond has completely cured. Wait 24 hours before using the clutch.

3) Align the arrow mark on the spider with the slot in the sliding sheave edge, and install the spider onto the fixed sheave.

b. Using the roller pin, install the collar and washer on the slider.

Roller pin tightening torque: 7.5 Nm (0.75 m· kg, 5.4 ft·lb)

Slot in sliding sheave,

4) While sliding the slider toward the spider, install the slider onto the sliding sheave. c. Install the spider, sliding sheave and fixed sheave 1) Install the sliding sheave, spider shim and washer onto the fixed sheave.

2) Apply Three Bond No. 1305 to the threaded portion of the fixed sheave.

Apply to the top four threads

-10-

5) According to "e-l) and 2)," install the tool (2) on the spider and tighten.

e. Tighten the sheave cap bolts.

Tightening torque: 15 Nm (1.5 m'kg, 11 ft路lb)

Tightening torque: 500 Nm (50 m' kg, 360 ft路lb)

5. Installing Hold the primary fixed sheave with the primary sheave holder, and torque the sheave bolt to specification.

1. Yamaha spider wrench YS-28890 90890-01711

WARNING: Since tightening torque is high, make sure the primary sheave, vise, and tools are tightely secured. Also take care not to crack the spider.

6)

Primary sheave holder: YS-1880 (U.S.A.) 90890-01701

Remove the primary sheave according to "2 Disassembly e-3".

Tightening torque: Tighten the bolt to A to properly seat the primary sheave on the crankshaft. Loosen the bolt, then torque it to B, the final torque.

d. Install the primary spring, and align the arrow mark on the sheave cap with the slot in the sliding sheave (and also with the arrow mark on the spider), and install the sheave cap.

A: 120 Nm (12 m'kg, 87 ft路lb) B: 58 Nm (5.8 m' kg, 42 ft路lb)

1. Sliding sheave slot 2. Spider arrow mark 3. Sheave cap arrow mark

- 11 -

E. Secondary sheave

Tightening torque: 4

~

7 Nm (0.4

~0.7

m¡kg. 2.9 ~ 5 ft'lb)

CAUTION:------------, Turn the screw securing the collar clockwise when viewed from the collar side. and lock the secondary shaft and collar. tighten the secondary sheave.

Check the ramp shoes on secondary sliding sheave for wear. Replace ramp shoes as required.

Sliding sheave

Fixed sheave

Tightening torque: 50 ~ 70 Nm (5.0

NOTE:

... -+ X -+

~

7.0 m¡kg. 36.2 ~ 50.6 ft'lb)

Greasing point No oiling or greasing is allowed

1. Removal a. Apply the brake and remove the secondary sheave mounting bolt. b. Remove the secondary sheave from the jack shaft.

2. Disassembly

a. Install the secondary sheave onto the tools (1) and (2) so that the fixed sheave faces downward.

WARNING:

Use extreme CAUTION when disassembling the secondary sheave. Serious injury can occur from the sudden release of spring tension. Use the Yamaha Secondary Sheave Assemoly Tool to contain the spring tension before removing the retaining circlip. DO NOT attempt this procedure unless you have the proper tools and understand the instructions thoroughly.

Secondary Compressor: 90890-01712 YS-28891 (U.S.A.) -12-

b. Hold the spring seat with the tool (3), screw in the tool (4), and separate the spring seat from the plain washer by pushing the spring seat downward.

d. Install the plain washer and circlip. e. Install the tools (3) and (4), and screw in the tool (4) to the position at which the splined portion of the spring seat nearly aligns with the splined portion of the fixed sheave.

c. Remove the circlip, and while screwing out the tool (4), set the secondary spring free. d. Remove the spring seat, secondary spring, sliding sheave and fixed sheave.

3. Inspection a. Inspect both sheaves. If either is warped, replace it. b. Inspect the ramp shoes on the sliding sheave; replace as necessary. c. Check the sheave bushings for wear; replace the sheave as required. d. Check the spring. If it is fatigued or damaged, replace it.

f. Bring the spring seat splines to align with the fixed sheave splines by hand.

4. Assembly a. Install the secondary fixed sheave and sliding sheave onto the tools (1) and (2). b. Hook the end of the secondary spring onto the spring hole in the sliding sheave. c. Hook the other end of the secondary spring onto the hole (indicated by No.) in the spring seat.

Std. spring position: No.3 hole

-13 -

NOTE: __________________________

i. Turn the sliding sheave the specified degrees in the c?unterclockwise direction, and screw in the tool (4) so that the spring seat engages with the sliding sheave.

Make sure that the three cams of the spring seat are in a position where they can move into the guide hole in the sliding sheave cam. g. Screw in the tool (4) so that the spring seat is splined to the sliding sheave.

Standard twist angle: 90°

1. Sliding sheave

h. Screw in the tool (4) to bring down the spring seat to a position where the spring seat cam does not contact the sliding sheave cam when they turn.

~----------Spring

j. Screw in the tool (4), and while pushing

the spring seat, fit the circlip to the fixed sheave to lock the spring seat.

seat cam

Clearnace

~-----Sliding

sheave cam

. Circlip

k. Remove the secondary sheave from the tool.

-14-

2. FRONT AXLE The A and B items under "4-1-F-3. Installation" in the SR540E are altered as follows:

A. Installation 1) Press-fit the sprocket wheels W4753-00) onto the front axle ..

(8R6-

50mm (.1.97 in) 99mm (3.90 in)

189.5 mm (7.46 in)

NOTE: _________________________ The right and left sprocket wheels shoud be installed so that the arrow marks on the A surfaces are aligned.

2) Secure both guide wheels to the front axle with the collar set bolts.

Tightening torque: 5.5 Nm (0.55 m¡ kg, 4 ft¡lb)

104 mm (4.09 in)

104 mm (4.09 in)

L/H GUIDE WHEEL

NOTE: __________________________________________________________ The left side guide wheel should be set to the position shown in the figure after installing the front axle onto the chassis.

-15-

3. FUEL TANK The "5-6. Fuel tank" in the SR540E is changed as follows:

....... __._ .. _. pipe

uel filter

1. Check all lines. If any are cracked, crimped or damaged in any way, replace them.

2. Be sure all lines are secured in place by a retaining clip.

3. Be sure that all lines are routed correctIy. The breather pipe must be routed so that no fuel will leak during operation.

4. Replace the fuel filter each season.

-16 -

4. BELLY PAN LID Two belly pan lids are attached to the front part of the belly pan. These lids should be used in the following manner.

,

1. Standard type As shown below, the holed lid is attached to the engine room side, and the blind lid is attached to the outside of the belly pan.

Holed lid Engine room side

Outside

Belly pan

2. When it is not so cold When it is not so cold in early spring, the blind lid should be removed and the

holed lid should be installed as shown below for better cooling of the engine and clutch.

Holed lid Engine room side

Outside

-17-

5. PULSER AND CHARGING COl L TEST The "6-1-G" in the SR540E is changed as fol!ows.

Pocket tester: YU-03112 Charging coil resistance: Black to Brown leads: 590 Q ± 10% at 20°C (68° F)

Check the resistance of each coil as shown in the illustration. If the resistance is not within specification, the coil is not working. Check the connections. If the connections are good, the coil is damaged internally; it should be replaced.

Pulser coil resistance: Black to White/Red leads: 15.1 Q ± 10% at 20°C (68°F)

®

Pulser coil ----Charge coil--

15.1 Q (Charge coil!

590Q (Pulser coil!

.QXl

r- "'--'----,..,...

I I I

L--::==-_*-CDCJ ®

®~

:i

__ 1 I _________ J

~--+®C>_-

1.

2.

3.

4.

5.

6.

7.

6. LIGHTING COl L TEST

Yellow Brown Black White/Red Flywheel magneto Pocket tester Set tester at "R x 1" position

the connections. If the connections are good, the coil is broken internally; it should be replaced.

The "6-2-C" in the SR540E is changed as follows.

Check the resistance between the yellow lead and ground. If the resistance is not within specification, the coil is not working. Check

Lighting coil resistance: Black & Yellow: 0.19 Q ± 10% at 20° C (68° F)

===T---® 0.,90"0%

~ o

Q x 1

~/'<Jr-_

1.

2.

3.

4.

5.

6.

7.

-18 -

Yellow Brown Black White/Red Flywheel magneto Pocket tester Set tester at "R x 1" position

,

SPECIFICATIONS * New specification (Compared with 1981 SR540E)

A. General Model Model: Model (I.B.M. No.) Frame I.D. & starting number Engine I.D. & starting number Dimension: Overall length Overall width (std) Overall height (W/windshield)

SR540F *SR540F (8R6) *8R6·027101 * SA535·0271 0 1 2,610 mm (102.7 in) 1,080 mm (42.5 in) 970 mm (38.2 in)

B. Engine Description: Engine type Engine model Displacement Bore x Stroke Effective compression ratio Starting system Ignition system Lubrication system

Axial fan cooled two-stroke, torque induction, twin cylinders SA535 535 cc (32.65 cu.in) 73 x 64 mm (2.874 x 2.52 in) 6.0: 1 Recoil hand starter C.D.I. "Autolube" oil injection

Cylinder head: Combustion chamber volume (with spark plug) Compression chamber type Head gasket thickness x q'ty

27.5 cc (1.68 cu.in) Dome + Squich 0.5 mm (0.02 in) x 1 pc.

Cylinder: Material Bore size Taper limit Out of round limit

Cast iron sleeves aluminum 73 mm (2.874 in) 0.05 mm (0.0020 in) 0.01 mm (0.0004 in)

Piston: Piston skirt clearance (measuring point) Piston oversize

Piston pin outside diameter x length Piston ring: Piston ring design Ring end gap (installed)

0.055 - 0.060 mm (0.0022 - 0.0024 in) [17 mm (0.67 in) from piston skirt end) 1st 73.25 mm (2.884 in) 2nd 73.50 mm (2.894 in) 3rd 73.75 mm (2.904 in) 4th 74.00 mm (2.913 in) cf> 20 x 56 mm (cf> 0.787 x 2.20 in) Keystone *0.2 - 0.4 mm (0.008 - 0.Q16 in)

Small end bearing: Type

Needle bearing

Big end bearing: Type

Needle bearing

Crankshaft: Crankshaft assembly width (A) Crankshaft assembly width (F) Crankshaft deflection (D)

200 ± 0.25 mm (7.87 ± 0.010 in) 6 +0 6 +0 o -0.05 mm (2.3 2 _ 0.002 in) D·1: 0.03 mm (0.0012 in) D·2: 0.04 mm (0.0016 in) D·3: 0.04 mm (0.0016 in) D·4: 0.05 mm (0.0020 in)

-19 -

Connecting rod big end side clearance (C) Connecting rod small end deflection (P)

0.25 - 0.75 mm (0.010- 0.030 in) 2.0 mm (0.079 in) I

-jf- P

Q I J

LI~A~~ Crank pin outside diameter x length Crank pin type Crank bearing type (Left) x q'ty Crank bearing type (Center) x q'ty Crank bearing type (Right) x q'ty Crank oil seal type (Left) x q'ty Crank oil seal type (Center) x q'ty Crank oil seal type (Right) x q'ty

et> 24 x 59 mm (et> 0.945 x 2.323 in)

Solid shaft assembly type with serration #6306 special x 2 pcs. #6206 special x 2 pcs. #6206 special x 1 pc.

FWJ-3278 9.5 TS x 1 pc.

Labyrinth seal x 1 pc.

FWJ-3248 10-1 TS x 1 pc.

Cooling fan: Fan belt tension

4 - 6 kg/8 mm (8.8 - 13.2Ib/0.31 in)

Carburetor: Type & manufacturer/quantity I.D. Mark Main jet (M.J.) Main air jet (M.A.J.) Power jet (Pw.J.) Power air jet (Pw.A.J.) Slow jet (S.J.) Slow air jet (S.A.J.) Pilot screw (P.S.) Starter jet (St.J.) Float height

B D44-38/K E I H I N/1 pc. *8R600 *#155 #180 #150 #170 #92 #100 *2.0 turns out #160 15+ 2 mm (O.59+ 0 .08 in) -3 -0.12 1500 r/min

Idling engine speed * Main jet setting chart

1""-

Temperature

Altitude Sea level

""

-600 m (2000 ttl -1200 m (4000 ttl -1800 m (6000 tt) -2400 m (8000 tt) - 3000 m (10000 tt)

_30oe ' (- 22°F) r----#155 1--#150 r----#145 1----#140 -#135 -#130

-20oe (_4°F)

... .. .. .... ....

oOe

-10oe (14°F)

(32°F) #150 #145 #140 #135

..

-..

#130

-

#125

-20-

.

..

- .... .. .. ..

200e (SSoF)

100e (50°F)

..

#145 #140 #135 #130 #125 #120

Intake reed valve: Type Bending limit Stopper height

V type 0.6 mm (0.024 in) * 12 ± 9.2 mm (0.4724± 0.0079 in)

Lubrication: Autolube pump - Color code Autolube pump - Minimum stroke Autolube pump - Maximum stroke Autolube pump - Reduction ratio Autolube pump - Output Min./200 strokes Autolube pump - Output Max./200 strokes Autolube pump wire free play Oil tank capacity Oil grade

*Gray 0.20 - 0.25 mm (0.0079 - 0.0098 in) 1.65 - 1.87 mm (0.0650 - 0.0736 in) * 1/36 0.95 - 1.19 cc (0.0321 - 0.0402 oz) 7.84 - 8.89 cc (0.2651 - 0.3006 oz) 25 ± 1 mm (0.98 ± 0.04 in) at idle 2.5 Liter (2.6 US. qt) YAMALUBE 2-cycle

C. Drive and track suspension Transmission: Type Drive ratio Engagement rpm Shfiting rpm Primary spring: Part No. Color code Secondary spring: Part No. Color code Secondary spring pre·load (twist)

V-belt automatic centrifugal engagement 3.5: 1 - 1 : 1 3400 - 3800 rpm * 6800 - 7200 rpm *90501-55672 * Green - Orange *90508-45508 * Green *90 0 (No.3 holes)

Sheave distance

270~g mm (10.63~g.11 in)

Sheave off·set V-belt width and outer line length V·belt wear limit

11 ± 0.5 mm (0.433 ± 0.020 in) 31.6 x 1,099 mm (1.24 x 43.3 in) 26 mm (1.02 in)

Track suspension: Type Damper type Spring color code (Front) Spring color code (Rear) Slide runner wear limit Track width Track deflection Length on ground Wheel sprocket material and number of teeth Stopper band length (Front) Stopper band length (Rear) Secondary drive: Type Reduction ratio Chain pitch x Number of links Free play Chain housing oil quantity Chain housing oil grade Brake: Type Brake pad thickness Brake pad wear limit Brake cable "L" distance Clearance between lining pad and disc

Slide rail suspension Oil and gas damper Red - Green No painted 10 mm (0.394 in) 381 mm (15 in) 25 - 30 mm/l0 kg (0.98 -1.18 in/22Ib) 942 mm (37.1 in) Double polyethylene 9 teeth *243 mm (9.57 in) (No.1 hole from the bottom) * 168 mm (6.61 in) (No.3 hole from the bottom) Chain (#35K-3) 17/31 (1 : 1.824) 9.525 mm (0.375 in) x 66L 10 + 5 mm (04+ 0.2 .m ) . -o.oa _2 250 cc (8.5 oz) Gear oil API "GL-3" (SAE #75 or 80) Floating disc type 5 mm (0.20 in) 1.0 mm (0.04 in) 57 mm (2.24 in) 0.15 - 0.3 mm (0.006 - 0.012 in) - 21-

D. Chassis Frame: Material Steering system: Caster (ski column) Chamber Ski length x width x thickness Ski stance Ski toe-out Steering linkage type Lock to lock angle (Ski) Steering angle

Aluminum + Steel 25° 0° 980 x 120 x 2 mm (38.6 x 4.7 x O.OS in) 880 mm (34.6 in) o mm (0 in) Tie-rod L: 27.9° R: 33.4° Right ski L: 33.4° R: 27.9° Left ski Right: 46° Left: 46°

Front suspension: Type (YAMAHA T.S. SUSPENSION) Damper type

Coil spring Oil and gas damper

Fuel tank: Capacity Fuel grade

26.6 L (5.9 Imp gal, 7.0 US gal) Regular gasoline

E. Electrical Ignition system: Type - flywheel magneto (C.D.I. Type) Model/Manufacturer Voltage Charging coil resistance Pulser coil resistance Ignition timing: B.T.D.C. Ignition coil: Manufacturer/Model/Quantity Spark gap Primary winding resistance Secondary winding resistance Diode (Yes or No)

F3T352/mitsubishi 12V *590 Q ± 10% at 20°C (68°F) (Brown-Black) *15.1 Q± 10%at20°C (68°F) (White/Red-Black) 1.5 mm (0.059 in)

i TOYO-DENSO HITACHI : YW-51/1 pc. *CM62·21/1 pc.

I I 9 mm (0.4 in)/300 rpm I 11 mm (0.6 in)/3,OOO rpm : 0.12 Q ± 10% at 0.15 Q ± 10% at I 20°C (6SoF) 20°C (68°F) I *3.6 kQ ± 10% at : 4.0 kQ ± 20% at I I 20°C (6SoF) 20°C (6SoF)* I I +No I

+:+-

Spark plug: Type & quality Spark pi ug gap

NGK BR9EV x 2 pcs.

0.7 ~ 0.8 mm (0.028 ~ 0.031 in)

Spark plug cap: Type Noise suppressor resistance

Resign type with noise suppressor 5 kQ ± 20% at 20°C (6SoF)

C.D.I. unit: Model/Manufactu rer Lighting system: Lighting output Lighting coil resistance Headlight type Bulb wattage/q'ty Tail/Brake light wattage

* SN4-20/MITSUBISH I 12V-100W 0.19 Q ± 10% at 20°C (68°F) (Yellow-Black) Halogen light 12V-60/55W x 1 pc.

12V-SW!23W

-22 -

A.C. regulator: Model/Manufacturer Voltage

*TRIZ,50 HITACHI or S85 16B TOSHIBA 13.8 ± 0.5V

F" Tightening torque Thread size

Part to be tightened [Engine] Spark plug Cylinder head Cylinder Flywheel magneto Crankcase upper and lower Tightening sequence

~-$

7

6 -

M14 M8 M8 M16 M8

Pl.25 Pl.25 Pl.25 Pl.0 Pl.25

M6

Pl.0

·3 ·2

Tightening torque 28 Nm (2.8 m"kg, 20 ft°lb) 25 Nm (2.5 mokg, 18 ft-lb) 25 Nm (2.5 mokg, 18 ft-lb) 73 Nm (7.3 mokg, 53 ftolb) First: 10 Nm (1.0 mokg, 7 ft-lb) Final: 20 Nm (2.0 mokg, 15 ft"lb) First: 5 Nm (0.5 m"kg, 3.5 ft°lb) Final: 10 Nm (1.0 mokg, 7 ft°lb)

/

·10 -------- -----

8-$ -$ 5

1.

4~

.9

-

11 ~

, Ring weight and stay

M6

Pl.0

10 Nm (1.0 mokg, 7.2 ft"lb)

Flywheel magneto and stay

M8

Pl.0

15Nm (l.5mokg,10.8ftolb)

Fan shaft and pulley 2 Starter pulley Crankcase and engine bracket

M16 Pl.0 M8 Pl.25 M8 Pl.25

43 Nm (4.3 mokg, 31.1 ftolb) 23 Nm (2.3 mokg, 16.5 ft"lb) 23 Nm (2.3 m"kg, 16.5 ft"lb)

M6 Pl.0 UNF 1/2"

15 Nm (1.5 mokg, 10.8 ft-lb) Initial: 120 Nm (12 m"kg, 87 ft"lb) Loosen once and retighten: 65 Nm (6.5 mokg, 47 ftolb) 64 Nm (6.4 mokg, 46 ftolb) 23 Nm (2.3 m"kg, 16.5 ftolb) 48 Nm (4.8 m"kg, 35 ft"lb) 60 Nm (6.0 mokg, 43.5 ft-lb) 48 Nm (4.8 m"kg, 35 ftolb) 23 Nm (2.3 mokg, 16.5 ft"lb) 85 Nm (8.5 mokg, 61.5 ft"lb) 23 Nm (2.3 mokg, 16.5 ft"lb) 64 Nm (6.4 m"kg, 46 ft-lb) 64 Nm (6.4 m"kg, 46 ftolb) 80 Nm (8.0 mokg, 58 ft°lb) 2.5 Nm (0.25 mokg, 1.8 ftolb)

[Drive and track suspension] Primary sliding sheave and cap Installation of primary sheave

Installation of secondary sheave Bearing housing Brake caliper and houisng chain Installation of drive chain sprocket Installation of driven chain sprocket Chain housing and frame Installation of front axle L.H. Front axle housing and frame Front pivot shaft Rear pivot shaft Rear axle Sliding runner [Chassis] Engine mounting bolt Steering column and gate

Remarks

M14 M8 Ml0 M20 Ml0 M8 M22 M8 Ml0 Ml0 M14 M6

Pl.5 Pl.25 Pl.25 Pl.0 Pl.25 Pl.25 Pl.0 Pl.25 Pl.25 Pl.25 Pl.25 Pl.0

Ml0 Pl.25 M8 Pl.25

52 Nm (5.2 m"kg, 37.6 ft°lb) 23 Nm (2.3 mokg, 16.5 ft"lb)

-23-

Use Neji Lock (Adhesive) Use Neji Lock (Adhesive)

Use motor oil

Use lock washer

Part to be tightened Steering gate Steering relay rod adjusting nut Steering lower bracket Installation of steering column 1,2 Steering relay ass'y Front shock absorber and bracket Bracket 1, 2 set bolt Front arm Ski installation

Thread size M8 Ml0 M8 M8 Ml0 M8 M6 Ml0 Ml0

Pl.25 Pl.25 Pl.25 Pl.25 Pl.25 Pl.25 Pl.0 Pl.25 Pl.25

Tightening torque 14 Nm (1.4 m·kg, 10 ft·lb) 47 Nm (4.7 m·kg, 34 fHb) 23 Nm (2.3 m·kg, 16.5 ft·lb) 14.5Nm (1.45m·kg,10.5ft·lb) 47 Nm (4.7 m·kg, 34 fHb) 21 Nm (2.1 m·kg, 15.2 ft·lb) 2 Nm (0.2 m·kg, 1.4 ft·lb) 16 Nm (1.6 m· kg, 11.6 ft·lb) 43 Nm (4.3 m·kg, 31.1 ft·lb)

-24-

Remarks

Use lock washer Use cotterpin

Particularly important information is distinguished in this manual by the following notations:

NOTE:

A NOTE provides key information to make procedures easier or clearer.

A CAUTION indicates special procedures that must be followed to avoid damage to the machine.

WARNING:

A WARNING indicates special procedures that must be followed to avoid injury to a machine operator or person inspecting or repairing the machine.

CONTENTS 3 3

I.

NEW SERVICE PROCEDURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

V-BELTCLUTCH .. .....................................

II.

SPECiFiCATION ......................................... 23

MAINTENANCE AND LUBRICATION CHART PERIODIC MAINTENANCE Every Check point

20 hrs. or 400km (250mi)

40 hrs. or 800km (500mi)

80 hrs. or 1,600 km (1,000 mil

When necessary

Seasonally

ENGINE: Tightness of bolts and nuts

0

Bends, cracks and wear

0

Abnormal noise

0

Loose connection and breaks of fuel and pulse pipes

0

Loose connection and breaks of oil pipes

0

Loose connection and breaks of oil delivery pipe

0 0

Manual rope starter system Carburetor:

• • •

Operation of starter jet

0

Mixing adjuster (pilot screwl

0

Idling speed adjustment

0 0

Operation and adjustment of oil pump

0

Ignition timing Engine compression

0 0

Cyl inder head/exhaust pipe decarbonization Fan belt tension, damage

0

Spark plug condition, gap and cleaning

0

Tightening of the cylinder head** DRIVE: Tightness of bolts and nuts

0

Wear on slide runners

0 0

Primary drive system 0

V·belt Secondary drive system

0

Sheave distance

0

Sheave offset

0

Brake pad wear

0

Brake operation and adjustment

0

Guide wheel rubber

0

Wear of drive track wheel sprocket

0

Drive track adjustment

0

Breaks in drive track

0

Bends in front and rear axles

0

Checking of lock washers

0

Drive chain 'adjustment

0

Drive chain oil level

0

BODY: Tightness of bolts and nuts

0

Bends and cracks

0

Welded/riveted, jOints

0

Ski adjustment

0

Breaks in fuel tank

0 0

Cleaning of fuel tank

0

Fuel filter Loose connection and breaks in fuel pipe

0

Breaks in oil tank

0 0

Oil filter * * Retighten every 10hours from the first use.

-1-

Every 20 hrs. or 400km (250mi)

Check point

40 hrs. or 800km (500mi)

80 hrs. or 1,600 km (1,000 mil

When necessary

Seasonally

ELECTRICAL: Wear, breakage of wire covering

0 0

Breaks in high-tension cord Voltage regulator working voltage

0

Operation of engine stop switch

0

Operation of tether switch

0

Headlight

0

Taillight

0

Brake light

0

LUBRICATION INTERVALS Every Lubrication point

20 hrs. or 400 km (250mi)

40 hrs. or 800km (500 mil

80 hrs. or 1,600 km (1,000 mil

When necessary

Seasonally

Oil/Grease Brand name

ENGINE: Starter case

0

Oil pump control box

0

Pump drive cover

0

Oil in the oil tank

Aeroshell grease #7A or Esso Beacon 325 grease 0

Y AMALUBE 2-cycle oil

DRIVE: Secondary shaft and sl id i ng sh eave

0

Front axle housing

0

Light all-purpose grease

Shaft 1 and shaft 2 (Slide rail) Drive chain oil replacement

Molybdenum disulfide snowmobile grease

0 0

Gear oil API GL-3 SAE #75 or #80

Steering column lower bearing

0

Light all-purpose grease

Steering column upper bearing

0

Motor oil

Steering links

0

Light all-purpose grease

Brake wire and stopper and brake lever

0

BODY:

0

Telescopic strut suspension

0

-2-

Esso Beacon 325 grease

I. NEW SERVICE PROCEDURE CARBURETOR Carburetor tuning 1. Standard specification The carburetor is set at the factory to run at temperatures of O°C to -20°C (32° F to _4° F) at sea level. If the machine has to be operated under conditions other than specified above, the carburetor must be reset as required.

Special care should be taken in carburetor setting so that pistons will not be holder or seized.

~ Altitude

-300e (_22°F) I

_20 0e (-4°FI I

Sea level #155 - 600 m (2,000 ttl #150 - 1,200 m (4,000 ttl #145 - 1,SOD m (6,000 tt)

...

..

.. ...

tt)

#130

Float height

15~~ mm (059 +0.079 in) .

-0.118

Idling engine speed

1,500 r/min

_10 0e

oOe

(14°F) I

(14°F)

100e (50°FI

200e (6SoFI

I

I

I

#150

... #145

...

..

..

.

#140

... #130

...

..

...

#145

....

...

... #135

...

- 2,400 m (S,OOO tt)

- 3,000 m (10,000

#150 #150 #92 2.0 turns out #160

...

#140

#135

Main jet Power jet Slow jet Pilot screw Starter jet

#125

...

. ...

#140

#135

....

...

#130

#125

.... #120

V-BELT CLUTCH

A. SHEAVE ALIGNMENT

NOTE: _ _ _ _ _ _ _ _ _ _ _ __

Sheave offset Place the sheave gauge against inner surfaces of the primary fixed sheave and the secondary sliding sheave. If the sheave gauge contacts the sheaves at four points as illustrated, the offset is correct.

The following items under "4-1. Drive" in the SR540E Service Manual will be changed as described below: A. Sheave adjustment B. Primary sheave C. V-belt D. Secondary sheave

-3-

NOTE: _ _ _ _ _ _ _ _ _ _ _ __

Adjustment If the center-to-center distance or offset is not within the specification, adjust it in the following manner: 1. Loosen the four engine mounting bolts.

By moving the engine back and forth, adjust the sheave distance so that the center-to-center distance between the primary sheave mounting bolt and secondary sheave mounting bolt is equal to the sheave gauge set specified above.

2. Adjust the thickness of shims on both ends of the secondary sheave so that the distance (offset) between the primary fixed sheave and secondary sliding sheave is equal to the sheave gauge.

Be sure to remove the V-belt before adjusting the sheave offset.

Sheave offset: 13 Âą 0.5 mm (0.51 Âą 0.02 in)

~ ~

Sheave gauge: YS-91047 (U.S.A.) 90890-01702 Sheave gauge adapter: YS-33274 90890-01718

Sheave distance If both ends of the primary shaft and the secondary shaft are aligned with the graduations, this indicates on the sheave gauge that the sheave distance is correct.

1. Adjusting shim

3.

Repeat steps 1 and 2 above until the sheave distance and sheave offset are adjusted correctly.

4. Tighten the engine mounting nuts while taking care not to move the engine.

Sheave distance: 270~g mm (1O.6~g.12 in)

Tightening torque: 52 Nm (5.2 m- kg, 37.6 ft-Ib)

-4-

NOTE:_ _ _ _ _ _ _ _ _ _ __ Select proper shims to be used at A and B. The total clearance at A and B should be 1.0 mm (0.4 in) or less.

90201-25526 (t = 2.0 mm) 90201-25527 (t = 1.0 mm) 90201-252F1 (t = 0.5 mm)

(t = 1.0 mm) 90201-222FO (t = 0.5 mm)

B. CLUTCH TUNING The clutch may require tuning depending upon the area of operation and the desired handling characteristics. The clutch can be changed by changing engagement & shifting rpm.

Clutch engagement rpm is defined as the engine speed where the machine first begins to move from a complete stop.

Shifting rpm is the engine speed when the machine passes a point 200 - 300 m (650 1,000 ft) from the starting position after the machine has been started at full-throttle from a dead stop.

Normally, when a machine reaches shift rpm, the vehicle splines Increases but the engine speed remains nearly constant. Under unfavorable conditions, however (wet snow, icy snow, hills, or rough terrain), engine speed can decrease after the engine has reached shifting rpm.

Engine rpm Engine rpm

Clutch shifting rpm

CI utch engagement rpm

t

Good condition

Bad condition Clutch shifting rpm

Clutch engagement rpm

--

Travelled distance

I-------t--_Starting position

Travelled distance

200 _ 300 m (650 -1,000 ttl

Starting position

-5-

-

200 _ 300 m (650 -1,000 ft)

CLUTCH SETTING DATA 1. Standard specification S.t.d. spec

High altitude spec

Engagement

r.p.m.

3,700 ± 200

4,200 ± 200

Shifting

r.p.m.

7,000 ± 200

+-

Parts No.

8U7-17643-00

8U7-17643-10

Set weight

28.6 kg

46.2 kg

1.73 kg/mm

2.4 kg/mm

Color

SILVER/RED

SILVER/GREEN

O'ty

1 p.c.

+-

8 U7 -17654-00

+-

Primary spring Spring constant

Spider shim Part No. O'ty

1 p.c. (t

= 1.4 mm)

+-

V-belt shim 8U9-17687-00

+-

A-1

A - 1 (Modify)

Part No.

8U7-17633-00

8U7-17633-10

Parts No.

90508-50571

+-

20°

50°

A - No.1

A- No.2

PINK

+-

Part No. Mark Weight

Twist angle Secondary spring Spring hole No. Color

NOTE: ___________________________________________________________ The "High altitude spec" supplies to operation at an altitude of more than 1,500 meters (4,500 feet).

2. How to change clutch engagement rpms and clutch shifting rpms.

~

Clutch engagement r.p.m.

Decreasing

Increasing

Decreasing

Increasing

-

-

Decrease

Increase

Decrease

Increase

-

-

Torsion spring constant

-

-

Decrease

Increase

Twist angle

-

-

Smaller wind

Greater wind

Spring constant

Primary spring Preload

Secondary spring

Clutch shifting r.p.m.

Primary clutch engagement rpm setting The factor which change the clutch engagement rpm is the primary spring preload.

Therefore, the clutch engagement rpm can be adjusted by replacing the primary spring itself.

For high altitude: 4,000 - 4,400 Secondary clutch shifting rpm setting The secondary clutch must be tuned to match snow and weather conditions. Tuning the clutch keeps the engine operating in the proper rpm range.

Standard clutch engagement rpm: 3,500 - 3,900

-6-

Standard clutch shifting rpm: 6,800 - 7,200

Secondary spring setting

spring Hole of sliding sheade

~

NO.1

No.2

No.3

No.4

C

10°

40°

70°

100°

A

20°

50°

80°

110°

B

30°

60°

90°

120°

1. Secondary spring position The spring seat is provided with four holes, No. 1 to 4, so that the secondary spring position can be changed as required.

Winding the spring more (i.e., from 10° to 40°) will increase the clutch shifting rpm and vise versa. Snow conditions will also require a change of the spring tension in order to attain the standard shifting rpm. The spring tension must be greater on wet snow than on packed snow. Less tension is needed on icy snow.

3. Secondary spring setting Std. secondary spring: PIN: 90508-50571 Color code: Pink Std. secondary spring position: A - No.1 Std. secondary spring twist: 20° The secondary spring settings are classified into two types as shown below.

Select a proper setting according to operating conditions. (For the setting procedure, refer to "d. Secondary Sheave.")

2. Secondary spring tension The secondary spring tension can be changed by moving the spring position from the free position in order to reset the clutch shifting rpm as required. The four holes are spaced at intervals of 30°.

Course

Lake surface

Trail and tour Position of spring seat and sliding sheave

Twist

Position of spring seat and sliding sheave

Twist

Icy snow

Std.

Std.

Std.

Std.

Packed snow

Std.

Std.

Std.

Std.

B - No. 1 or C - No.2

30° or 40°

Std. or B - No.1

Std. or 30°

Spring factor

Wet snow

-7-

Co PRIMARY SHEAVE

V-belt shim

Tightening torque: First tighten the bolt to a torque of A, then loosen it. Retighten bolt to a final torque of B. A: 120 Nm (12 mokg, 87 ftolbl B: 58 Nm (5.8 mokg, 47 ftolbl

Sheave cap

•

173 Nm (17.3 mokg, 125 ftolbl

Apply Loctite® #262 to the top four threads.

Loctite #262 Weight pin

•

~ Oiling

Sheave cap bolt

point

NOTE: X ~ No oiling or greasing is allowed.

-8-

Removal 1. Remove the drive guard, and remove the V-belt.

2. Hold the fixed sheave with the primary sheave holder and remove the clutch retaining bolt and washer. Drive the primary sheave off the crankshaft with the primary sheave puller.

Disassembly 1. Loosen the six sheave cap bolts.

2. Remove the sheave cap and spring.

3. Remove the primary sheave by using the clutch sprider separater.

Yamaha spider wrench: 90890-01711 YS-28890 (U.S.A.) Center post: YS-33273 (cp = 14 mm)

To remove the clutch, a sheave puller and a sheave holder are required.

1. Center post (YS¡33273)

1. Sheave puller 2. Sheave holder

Primary sheave holder: YS-01880 (U.S.A.) 90890-01701 Primary sheave puller: YS-33272 (U.S.A.) 90890-01719

-9-

WARNING:

To loosen the spider, high torque is required and therefore, make sure the primary sheave, vise, and tools are tightely secured also take care not to crack the spider.

Bush inside diameter

Sheave cap

Sliding sheave

Standard

28.6 mm (1.23 in)

41.7 mm (1.64 in)

Wear limit

0.25 mm (0.01 in)

0.25 mm (0.01 in)

3. Weights Check the bushing bore inside diameter of each weight and its contact surface with the collar. If worn more than limits, replace them with new ones.

Do not use steal wool or a wire brush to clean components having a duralon bushing: damage will result it bushing is contacted with the steal wool or a wire brush.

Wear limit

Inspection I nspect the tapered ends of the crank¡ shaft and the primary fixed sheave for scraches. If either is severely scratched, replace it. If scratches are minor, burnish the component with emery cloth.

2. Bushings Check the primary sheave cap bushing and the sliding sheave bushing for wear.

If worn beyond tolerance, replace the bushing, or cap assembly.

Bushing bore diameter (d) 6.7mm (0.26 in)

Contact surface with collar A

B

0.5mm (0.021 in)

i.o mm (0.04 in)

1.

Contact surface with collar

4.

Roller Check the inside diameter of the roller bushing, then check the contact surface of the roller and the weight. If either surface is worn unevenly or more than acceptable limits, replace them.

Wear limit

-10-

Bushing bore diameter (d)

Contact surface with weight (0)

9.9 mm (0.39 in)

13.0 mm (0.51 in)

a. Make sure the threads of the pivot bolt are clean and dry, and apply a generous amount of red loctiteÂŽ #262 to the threads of each bolt. b. Immediatly install new lock nuts on pivot bolts, and tighten them until they just touch the aluminum casting. Never reuse lock nuts.

Contact surface with weight

Uneven wear -~

~===:::::j----t

I

I========l---t

I

---r--d -0-----+__ ----1

Do not over tighten the pivot-bolt nuts; overtightening may cause binding of the weight arms. Check the operation of the weight arms after tightening the pivot-bolt nuts.

If the outer surface of the roller is worn unevenly, the roller is probably seized to the pin. Be sure to check the roller pin.

5. Weight pins and roller pins Check both weight and roller pins. If metal dust collects on pins, remove it using sandpaper (#800 - #1,000). If the pin is damaged or bent, replace the pin with a new one.

6. Spider Check the contact surface of the spider with the slider. If it is worn more than limits or cracked, replace it with a new one.

VVARNING:

To maintain the balance of the clutch, the pivot bolts all must be installed with their threaded portions pointing in a clockwise direction; see illustration 1.

Maximum clearance: 2.0 mm (0.08 in)

1. Wear limit

ILLUSTRATION 1

7. Primary spring Check the primary spring for damage or fatique, and replace it as required.

2. Install the spider, sliding sheave and fixed sheave.

Assembly 1. Pay attention the following points when replace the weight arm.

NOTE: Install the duralon bushing carefully so it is not damaged.

-11 -

a. Install the sl iding sheave, spider shim, V-belt shim onto the fixed sheave. b. Apply Loctite® #262 to the threaded portion of the fixed sheave.

WARNING:

Since tightening torque is high, make sure the primary sheave, vise, and tools are tightely secured. Also take care not to crack the spider.

Apply to the top four threads

3. Tighten the sheave cap bolts.

Fixed sheave

Apply Loctite® #262 to:

Tightening torque: 14 Nm (1.4 m'kg, 10 ft·lb)

Spider shim

NOTE: _________________________

J_~t==r 4 threads

Make sure the cap bolts are clean and dry.

Apply blue Loctite® Lock N'Seal to the threads of the bolts.

Outer surface of bushing (large)

1. Loctite® should be applied only to the area specified. Never apply to the outer surface of the bushing (large) and other areas.

2. Do not use the clutch until the Loctite® has completely cured. Wait 24 hours before using the clutch.

Installing Hold the primary fixed sheave with the primary sheave holder, and torque the sheave bolt to specification.

Primary sheave holder: YS-1880 (U.S.A.) 90890-01701

c. Tightening the spider with special tool.

Tightening torque: 173 Nm (17.3 m'kg, 125 ft·lb)

Tightening torque: Tighten the bolt to A to properly seat the primary sheave on the crankshaft.

Loosen the bolt, then torque it to B, the final torque.

A: 120Nm(12m·kg,87ft·lb) B: 70 Nm (7.0 m' kg, 49 ft·lb)

-12 -

D. SECONDARY SHEAVE

Jackshaft /4-7 Nm (0.4-0.7 m¡kg,

2.9-~

thel:scre~

,

Turn securing the collar clockwise when viewed from the collar side, and lock the secondary shaft and collar, tighten the secondary sheave.

/

~~,

~~~

'" ~ Plaine washer CircliP _ _---W~ Spring seat '~

~ "00""',,,

~~

Check the ramp shoes on secondary sliding sheave for wear. Replace reamp shoes as re¡1 quired.

~

'P';o, Sliding sheave

_

'

X~-

Fixed sheave

NOTE: .-'Greasing point N.B.:

..........

X-,...-No oiling or greasing is allowed

Removal 1. Apply the brake and remove the secondary sheave mounting bolt.

2. Remove the secondary sheave from the jack shaft.

Disassembly WARNING:

Use the Yamaha Secondary Compressor to contain the spring tension before removing the retaining circlip. DO NOT attempt this procedure unless you have the proper tools and understand the instructions thoroughly.

-13-

1.

I nstall the secondary sheave onto the secondary sheave compressor so that the fixed sheave faces downward.

2. Hold the spring seat with the sheave compressor, screw in the wing nut.

3. Remove the circlip, and while screwing out the wing nut set the secondary spring free.

Assembly 1. Grease the secondary shaft, and sliding sheave boss and mount the sliding sheave on the shaft.

Recommended grease: Molybdenum disulfide snowmobile grease

Secondary Compressor: YS-28891 (U.S.A.) 90890-01712

2. Install the secondary fixed sheave and

3.

1. Secondary sheave compressor

4.

sliding sheave onto the secondary sheave compressor.

Hook the end of the secondary spring onto the spring hole in the sliding sheave.

Hook the other end of the secondary spring onto the hole (indicated by No.) in the spring seat.

Std. spring position: A - No.1 hole

4. Remove

the spring seat, secondary spring, sliding sheave and fixed sheave.

Inspection 1. Inspect both sheaves. If either is warped, replace it.

2. Inspect the ramp shoes on the sliding sheave, replace as necessary.

3. Check the sheave bushings for wear; replace the sheave as required.

4. Check the spring. If it is fatigued or damaged, replace it.

5.

-14-

Install the plain washer and circlip.

6. Screw in the wing nut to the position at which the splined portion of the spring seat nearly alignes with the splined portion of the fixed sheave.

10. Turn the sliding sheave the specified degrees in the counterclockwise direction, and screw in so that the spring seat engages with the sliding sheave.

Standard twist angle: 20°

7. Bring the spring seat splines to align with the fixed sheave splines by hand.

11. Screw in the wing nut, and while pushing the spring seat, fit the circlip to the fixed sheave to lock the spring seat.

NOTE: _ _ _ _ _ _ _ _ _ _ _ __

Make sure that the three cams of the spring seat are in a position where they can move into the guide hole in the sliding sheave cam.

12.

8. Screw in the wing nut so that the spring seat is splined to the sliding sheave.

9. Screw in the wing nut to bring down the spring seat to a position where the spring seat cam does not contact the sliding sheave cam when they turn.

- 4 - - - - Spring seat cam

Sliding sheave cam

-15 -

Install the secondary sheave assembly and adjust the sheave off-set.

Lubrication of transmission To keep the machine in the best operating condition, the sheaves should be lubricated with low temperature grease and motor oil periodically as illustrated.

+-.

1. Do not apply grease to the area marked

X. For other parts, oiling is unnecessary.

2. When installing the primary sheave, clean the oil off the taPered portion of crankshaft using a lacquer thinner.

Oiling point

+- X Free from oil +-

Greasing point

-16-

Eo FRONT SUSPENSION Installation

s-u-b-a-ss-em-~-IY-'- -r~l-

'D-a-m-pe-r

-

i

---

I _J

-; --1 ~

.

I

'~l

, I

e9 I

~--'

I I I I I I I I I

I I

I I I I

I I

I L- _ _ _ _ _ _ _ _ _ _ .JI

I

Arm outside

I

2Nm (0.2 m-kg, 1.4 ftolb)

21 Nm (2.1 mokg, 15.2 ftolb)

NOTE:

Greasing .... .pOint .

43 Nm (4.3 m-kg, 31.1 ftolb)

(ESSO beacon 325)

-17-

F. REAR SUSPENSION Removal NOTE: _ _ _ _ _ _ _ _ _ _ __ @

It is advisable to loosen the track adjusting nut and the rear axle nut.

-----.---

1. Remove the two front pivot shaft mounting bolts and four rear pivot shaft mounting bolts.

---

I

1. Wear limit: 10 mm (0.4 in) 2. New:: 15 mm (0.6 in)

2. Check the suspension wheel for damage.

If damaged, replace it.

"DE CARBON" type shock absorber WARNING:

These shock absorbers contain highly pressurized nitrogen gas.

Read and understand the following information before handling the shock absorber. The manufacturer cannot be held responsible for property damage or personal injury that may result from improper handling.

1. Do not tamper with or attempt to open the cylinder assembly. Injury may result.

2. Do not subject shock absorber to an open flame or other high heat. This may cause the unit to explode due to excessive gas pressure.

3. Do not deform or damage the cylinder in any way. Cylinder damage will result in poor damping performance.

4. Gas pressure must be released before disposing of the shock absorber. To do so, drill a 2 - 3 mm (0.08 - 0.12 in) hole through the cylinder wall at a point 10 - 15 mm (0.4 - 0.6 in) above the bottom of the cylinder.

2. Remove the slide rail suspension assembly.

1. Front shock

2. Rear shock

Inspection 1. Check to see if slide runners are worn excessively. If the slide runner thickness is less than specified value, replace slide runner.

10 -15 mm (0.4 -0.6 in)

Wear limit: 10 mm (0.4 in) Slide runner securing screw tightening torque: 4.5 Nm (0.45 m' kg, 3.3 ft¡lb)

2 -3 mm (0.08-0.12 in)

"'

1-

"" ' I

-18 -

WARNING: Wear eye protection to prevent eye damage from escaping gas and/or metal chips.

1. Check the rod, and if it is bent or damaged, replace the shock absorber.

2. Check for oil leakage. If oil leakage is evident, replace the shock absorber.

3. By compressing the shock absorber, check to see there is no gas leakage.

1. Stopper band

Slide rail suspension adjustment The setting of suspension greatly affects the stability and steering of the machine. Therefore, it is necessary to adjust the suspension setting according to course conditions and rider's driving technique.

1. Front stopper band setting The height (L) of the front suspension can be properly adjusted by changing the length of the stopper band.

No.5 NO.4

No.3 No.2 No.1 (STD)

1. Stopper band

Standard setting: No.1 hole from the bottom Tightening torque: 3.8 Nm (0.38 m' kg, 2.75 ft¡lb)

This adjustment will affect the stability and maneuverability of the machine.

Snow condition

Length of stopper band

Track side slip

Performance of straight running

Bumping and pitching

Riding comfort

Lower (No.5)

Increase

Poor

Less

Poor

Std. (No.1)

Normal

Normal

Normal

Normal

Lower

Increase

Good

--

Poor

Std. (No.1)

Normal

Normal

--

Normal

Hard packed

Soft deep snow

Rear stopper band setting The height (L) of the rear suspension can be properly adjusted by changing the length of the stopper band.

Standard setting: No.1 hole Tightening torque: 3.8 Nm (0.38 m' kg, 2.75 ft¡lb)

- 19--

No.5 No.4 No.3 No.2 No.1 (STD)

1. Stopper band

This adjustment will affect the stability and meneuverability of the machine.

Handling

Track side slip

Performance of straight running

Bumping and pitching

Riding comfort

Lower

Hard

Decrease

Good

More

Poor

Std. (No.1)

Normal

Normla

Normal

Normal

Normal

i

Main arm adjustment

Front side spring

The location of the main arm can be changed on this model. This helps to control acceleration when the machine pulls out.

~ No.2

1. Normal riding (less gap) Std. weight rider (No.2)

- --- --------- -- - ---- - - - - -- --

2. Trail riding (more gap) Heavy weight rider

Rear side spring 1. Main arm

Sett i ng facto r Packed, wet Ice snow

2. Lower

3. Upper (Std.)

Handling

Performance of straight running

Std.

Normal

Std.

Normal

No.2

Poor

No.2

Increase

Std.

Normal

Std.

Normal

No.2

Poor

No.2

Decrease

Deep snow

~

Rear spring

The rear springs are determining factor in machine stability.

Consider the ground surface condition and the rider's weight when setting rear springs.

The suspension should be set as soft as possible, unless it impairs the stability of the machine.

-20-

No.4

1. Normal riding (less gap) Std. weight rider (No.1)

No.1

2. Trail riding (more gap) Heavy weight rider

Front side rear spring

~

Track side slip

Hard packed performance of straight running

Deep snow

Handling

+-

Riding comfort

Increase

Poor

Decrease

Good

Poor

Poor

Decrease

Good

Increase

Poor

Good

Good

Handling

Track side slip

Performance of straight riding

Riding comfort

Heavy weight rider

Increase

Good

Increase

Poor

Poor

Good

Decrease

Poor

Decrease

Good

Good

Poor

Rear side rear spring

-------------

Installation Grease the slide rail suspension as indicated by arrows in the illustration.

For easy installation of the slide rail suspension in the frame, proceed as follows .

...

---

----

-~-.--~--.-.--.--~- -~

-

/

I /

----.--.--.--------.-----.~--

----_.-

NOTE: _ _ _ _ _ _ _ _ _ _ __

1. Fully loosen the drive track adjusting screws.

2. Place the slide rail suspension into track and fit the forward pivot shaft using washers and bolts.

Install bolts finger-tight. Bolts will be tightened to proper torque when slide rail installation is complete.

3. Fit the rear pivot shaft to the frame. The rear pivot shaft is being forced toward the rear by the shock absorber.

-21 -

NOTE: _________________________ When installation of slide rail is complete, tighten front and rear bolts to proper torque.

Tightening torque: Front pivot shaft mounting bolt: 64 Nm (6.4 m路 kg, 46 ft路lb) Rear pivot shaft mounting bolts: 64 Nm (6.4 m路 kg, 46 ft路lb) 4. Adjust the track tension by turning the track adjusting nuts.

-22-

SPECI FICATIONS A. General

* New specification (Compared with 1982 SR540F) Model

SR540G

Model: Model (I.B.M. No.) Frame 1.0. & Starting number Engine 1.0. & Starting number

*SR540G (8U7) *8R6-039101 *SA535

Dimension: Overall length Overall width (Std.) Overall height (W/windshield)

*2,675 mm (105.3 in) 1,080 mm ( 42.5 in) 970 mm ( 38.2 in)

B. Engine Model Description: Engine type Engine model Displacement Bore x Stroke Effective compression ratio Starting system Ignition system Lubrication system

SR540G Axial fan cooled two-stroke, torque induction, twin cylinders SA535 535 cc (32.65 cu.in) 73 x 64 mm (2.874 x 2.52 in) 6.0: 1 Recoil hand starter C.D.1.

"Autolube" oil injection

Cylinder head: Combustion chamber volume (with spark plug) Compression chamber type Head gasket thickness x Q'ty

*25.5 cc (1.68 cu.in) Dome + Squich 0.5 mm (0.02 in) x 1 pc.

Cylinder: Material Bore size Taper limit Out of round limit

Cast iron sleeves aluminum 73 mm (2.874 in) 0.05 mm (0.0020 in) 0.01 mm (0.0004 in)

Piston: Piston skirt clearance (measuring point) Piston oversize

Piston pin outside diameter x Length

0.055 - 0.060 mm (0.0022 - 0.0024 in) [17 mm (0.67 in) from piston skirt end] 1st 73.25 mm (2.884 in) 2nd 73.50 mm (2.894 in) 3rd 73.75 mm (2.904 in) 4th 74.00 mm (2.913 in) cfJ 20 x 56 mm (cfJ 0.787 x 2.20 in)

Piston ring: Piston ring design Ring end gap (installed)

Keyston'e 0.2 - 0.4 mm (0.008 - 0.016 in)

Small end bearing: Type

Needle bearing

Big end bearing: Type

Needle bearing

Crankshaft: Crankshaft assembly width (A)

200 ± 0.25 mm (7.87 ± 0.010 in)

Crankshaft assembly width (F)

60 ~ g.osmm (2.362

Crankshaft deflection (D)

0·1: 0.03 mm (0.0012 in) 0·3: 0.04 mm (0.0016 in) -23-

~ g.002 in) 0·2: 0.04 mm (0.0016 in) 0-4: 0.05 mm (0.0020 in)

SR540G

Model Connecting rod big end side clearance (C) Connecting rod small end deflection (P) 0-1

0.25 - 0.75 mm (0.010 - 0.030 in) P 2.0 mm (0.079 in)

0-2 0-3

I~I!

!

L ___ I

Crank Crank Crank Crank Crank Crank Crank Crank

Df-

I

'J

0-4

:

~ A_~-FI

x 59 mm (cf> 0.945 x 2.323 in) Solid shaft assembly type with serration #6306 special x 2 pcs. #6206 special x 2 pcs. #6206 special x 1 pc.

FWJ-3278 9.5 TS x 1 pc.

Labyrinth seal x 1 pc.

FWJ-3248 10-1 TS x 1 pc.

pin outside diameter x Length pin type bearing type (left) x Q'ty bearing type (Center) x Q'ty bearing type (Right) x Q'ty oil seal type (Left) x Q'ty oil seal type (Center) x Q'ty oil seal type (Right) x Q'ty

cf> 24

Cooling fan: Fan belt tension

4 - 6 kg/8 mm (8.8 - 13.2 Ib/0.31 in)

Carburetor:: Type & Manufacturer/Quantity 1.0. Mark Main jet (M.J.) Main air jet (M.A.J.) Power jet (Pw.J.) Power air jet (Pw.A.J.) Slow jet (S.J.) Slow air jet (S.A.J.) Pilot screw (P.S.) Starter jet (St.J.)

B044-38/KE I HI N/l pc. *8R601 *#150 #180 #150 #170 #92 #100 2.0 turns out #160

Float height

15 + 2 mm (0.59 + 0.08 in)

Idling engine speed

1,500 r/min

- 3

- 0.12

*Main jet setting chart

~ Altitude

-30°C (-22°FI

-20°C (-4°FI

-10"e (14°FI

I

I

I

•

Sea level

F#155 - 600 m (2,000 ttl r---#150 - 1,200 m (4,000 ttl r---#145 - 1,800 m (6,000 ttl

..

.

• -#135

- 3,000 m (10,000 ttl -#130

.

.. .. ..

r---#140 - 2,400 m (8,000 ttl

..

.

..

-24-

10°C (50°FI

20°C (68°FI

I

I

I

#150

#145

#140

#135

. ..

..

...

..

. . ..

#130

• #125

•

oOe (14°FI

..

#145----

#140

#135

.

#130

.

#125----

#120

Model

SR540G

Intake reed valve: Type Bending limit Stopper height

V type 0.6 mm (0.024 in) 12 ± 0.2 mm (0.4724 ± 0.0079 in)

lubrication: Autolube pump - Color code Autolube pump - Minimum stroke Autolube pump - Maximum stroke Autolube pump - Reduction ratio Autolube pump - Output Min'/200 strokes Autolube pump - Output Max./200 strokes Autolube pump wire free play Oil tank capacity Oil grade

Gray 0.20 - 0.25 mm (0.0079 - 0.0098 in) 1.65 - 1.87 mm (0.0650 - 0.0736 in) 1/36 0.95 - 1.19 cc (0.0321 - 0.0402 oz) 7.84 - 8.89 cc (0.2651 - 0.3006 oz) 25 ± 1 mm (0.98 ± 0.04 in) at idle 2.5 l (2.6 US qt, 2.2 Imp qt) Yamalube 2-cycle

C. Drive and track suspension Model Transmission: Type Drive ratio Engagement rpm Shifting rpm Primary spring: Part No. Color code Secondary spring: Part No. Color code Secondary spring pre·load (twist) Sheave distance Sheave off-set V-belt width and outer line length V-belt wear limit

SR540G V-belt automatic centrifugal engagement 3.5: 1 - 1 : 1 *3,500 - 3,900 rpm *6,800 - 7,200 rpm *8U7 -17643-00 *Silver - Red *90508-50571 *Pink * 20 0 (No.1)

270~~ mm(10.63~g.11 in) *13 ± 0.5 mm (0.433 ± 0.020 in) 31.6 x 1,099 mm (1.24 x 43.3 in) 26 mm (1.02 in)

Track suspension: Type Damper type Spring color code (Front) Spring color code (Rear) Slide runner wear limit Track width Track deflection length on ground Wheel sprocket material and number of teeth Stopper band length (Front) Stopper band length (Rear)

Slide rail suspension Oil and gas damper No painted No painted 10 mm (0.394 in) 381 mm (15 in) 25 - 30 mm/10 kg (0.98 -1.18 in/22Ib) 902 mm (35.5 in) Double polyethylene 9 teeth *250 mm ( 9.84 in) (No.1 hole from the bottom) *267 mm (10.51 in) (No.1 hole from the bottom)

Secondary drive: Type Reduction ratio Chain pitch x Number of links

Chain (#35-3) 17/31 (1 : 1.824) 9.525 mm (0.375 in) x 66l

Free play

10~~

Chain housing oil quantity Chain housing oil grade

250 cc (8.5 oz) Gear oil API "Gl-3" (SAE #75 - 80)

-25-

mm

(0.4~g:~8in)

SR540G

Model Brake: Type Brake pad thickness Brake pad wear limit Brake cable "L" distance Clearance between lining pad and disc

Floating disc type 5 mm (0.20 in) 1.0 mm (0.04 in) 57 mm (2.24 in) 0.15 - 0.3 mm (0.006 - 0.012 in)

D. Chassis Model

SR540G

Frame: Material

Aluminum

Steering system; Caster (ski column) Chamber Ski length x Width x Thickness Ski stance Ski toe-out Steering linkage type Steering angle

+ Steel

25° 0° 980 x 120 x 2 mm (38.6 x 4.7 x 0.08 in) 880 mm (34.6 in) o mm (0 in) Tie-rod Right: 46° Left: 46° L: 27.9° R: 33.4° Right ski L: 33.4° R: 27.9° Left ski

Lock to lock angle (Ski) Front suspension: Type (YAMAHA T.S. SUSPENSION) Damper type

Coil spring Oil and gas damper

Fuel tank: Capacity Fuel grade

26.6 L (5.9 Imp gal, 7.0 US gal) Regular gasoline

I

E. Electrical Model

SR540G

Ignition system: Type - Flywheel magneto (C.D.1. Type) Model/Manu factu rer Voltage Charging coil resistance Pulser coil resistance

F3T352/MITSUBISHI 12V 5900 ± 10% at 20°C (68°F) 15.10 ± 10% at 20°C (68°F)

Ignition timing: B.T.D.C.

1.5 mm (0.059 in), 15° at 7,000 r/min

Ignition coil: Manufacturer/Model/Quantity Spark gap Primary winding resistance Secondary winding resistance Diode (Yes or No) Spark plug: Type & Quality Spark plug gap

HITACHI !

CM62-21 /1 pc.

9 mm (0.4 in)/300 rpm 11 mm (0.6 in)/3,000 rpm 0.150 ± 10% at 20°C (68°F) 3.5 kO ± 10% at 20°C (68°F) No

(Brown - Black) (White/Red - Black)

TOYO-DENSO YW-51/1 pc. ++-

0.120 ± 10% at 20°C (68°F) 4.0 kO ± 20% at 20°C (68°F) +-

NGK BR9EV x 2 pcs.

0.7 - 0.8 mm (0.028 - 0.031 in)

-26-

Model

SR540G

Spark plug cap: Type Noise suppressor resistance

Resign type with noise suppressor 5 k,Q ± 20% at 20°C (68°F)

C.D.1. unit: Model/Manufacturer

8N4-20/M ITSUBISH I

Lighting system: Lighting output Lighting coil resistance Headlight type Bulb wattage/Q'ty Tail/Brake light wattage

12V-100W 0.19,Q ± 10% at 20°C (68°F) (Yellow - Black) Halogen light 12V -60/55W x 1 pc.

12V-8W/23W I

A.C. regulator: Model/Manufacturer Voltage

TRIZ-50/HITACHI or S85 16B/TOSHIBA 13.8 ± 0.5V

F. Tightening torque Part to be tightened Engine: Spark plug Cylinder head Cylinder Flywheel magneto Crankcase upper and lower: Tightening sequence:

Tightening torque mokg ftolb Nm

Thread size

First Final First Final

M14 M8 M8 M16 M8 M8 M6 M6

P1.25 P1.25 P1.25 P1.0 P1.25 P1.25 P1.0 P1.0

~-$

6

7 -

. - .. __ ... "

_-

-

8~~ 5

28 25 25 73 10 20 5 10

$3

1.

-

4-2

2.8 2.5 2.5 7.3 1.0 2.0 0.5 1.0

Remarks

20 18 18 53 7 15 3.5 7

I ·10

------ ---

4~

$9 11

~

Ring weight and stay

M6

P1.0

10

1.0

7

Flywheel magneto and stay

M8

P1.0

15

1.5

10.8

Fan shaft and pulley 2 Starter pulley Crankcase and engine bracket

M16 P1.0 M8 P1.25 M8 P1.25

43 23 23

4.3 2.3 2.3

31.1 16.5 16.5

M6

P1.0

15

1.5

10.8

UNF UNF M14 M8 M10 M20 M10 M8 M22

1/2" 1/2" P1.5 P1:25 P1.25 P1.0 P1.25 P1.25 P1.0

120 65

12 6.5 6.4 2.3 4.8 6.0 4.8 2.3 8.5

87 47 46 16.5 35 43.5 35 16.5 61.5

Drive and track suspension: Primary sliding sheave and cap Installation of primary sheave: Initial Loosen once and retighten Installation of secondary sheave Bearing housing Brake caliper and housing chain Installation of drive chain sprocket Installation of driven chain sprocket Chain housing and frame Installation of front axle L.H.

-27 -

64 23 48 60 48 23 85

Use Loctite® (Adhesive) Use Loctite® (Adhesive)

Use m~tor oil

Part to be tightened Front axle housing and frame Front pivot shaft Rear pivot shaft Rear axle Sliding runner Chassis: Engine mounting bolt Steering column and gate Steering gate Steering relay rod adjusting nut Steering lower bracket Installation of steering column 1,2 Steering relay ass'y Front shock absorber and bracket Bracket 1, 2 set bolt Front arm Ski installation

MS Ml0 Ml0 M14 M6

Pl.25 Pl.25 Pl.25 Plo25 PLO

Tightening torque Nm ft'lb m'kg 16.5 23 2.3 46 64 6.4 46 64 6.4 SO S.O 5S 1.S 2.5 0.25

Ml0 MS MS Ml0 MS MS Ml0 MS M6 Ml0 Ml0

Pl.25 Pl.25 Pl.25 Pl.25 Pl.25 Pl.25 Pl.25 Pl.25 PLO Pl.25 Pl.25

52 23 14 47 23 14.5 47 21 2 16 43

Thread size

-2S -

5.2 2.3 1.4 4.7 2.3 1.45 4.7 2.1 0.2 1.6 4.3

37.6 16.5 10

Remarks

Use lock washer

34

16.5 10.5 34 15.2 1.4 11.6 31.1

Use lock washer Use cotterpin

MAINTENANCE AND LUBRICATION CHART PERIODIC MAINTENANCE Every Check point

20 hrs. or 400 km (250mi)

40 hrs. or 800 km (500mi)

80 hrs. or 1,600 km (1,000 mil

When necessary

Seasonally

ENGINE: 0

Tightness of bolts and nuts Bends, cracks and wear

0

Abnormal noise

0

Loose connection and breaks of fuel and pulse pipes

0

Loose connection and breaks of oil pipes

0

Loose connection and breaks of oil delivery pipe

0 0

Manual rope starter system Carburetor:

• • •

0

Operation of starter jet

0

Mixing adjuster (pilot screw) Idling speed adjustment

0 0

Operation and adjustment of oil pump

0

Ignition timing Engine compression

0 0

Cylinder head/exhaust pipe decarbonization Fan belt tension, damage

0

Spark plug condition, gap and cleaning

0

Tightening of the cylinder head** DRIVE: Tightness of bolts and nuts

0

Wear on slide runners

0

Primary drive system

0

V-belt

0

Secondary drive system

0

Sheave distance

0

Sheave offset

0

Brake pad wear

0

Brake operation and adjustment

0

Guide wheel rubber

0

Wear of drive track wheel sprocket

0

Drive track adjustment

0

Breaks in drive track

0

Bends in front and rear axles

0

Checking of lock washers

0

Drive chain adjustment

0

Drive chain oil level

0

BODY: Tightness of bolts and nuts

0

Bends and cracks

0

Welded/riveted, joints

0

Ski adjustment

0

Breaks in fuel tank

0

Cleaning of fuel tank

0

Fuel filter

0

Loose connection and breaks in fuel pipe

0

Breaks in oil tank

0

Oil filter

0

* * Retighten every 1Ohours from the first use.

-1-

Every 20 hrs. or 400km (250mi)

Check point

40 hrs. or 800km (500mi)

80 hrs. or 1,600 km (1,000 mil

When necessary

Seasonally

ELECTRICAL: 0

Wear, breakage of wire covering 0

Breaks in high-tension cord

0

Voltage regulator working voltage Operation of engine stop switch

0

Operation of tether switch

0

Headlight

0

Taillight

0

Brake light

0

LUBRICATION INTERVALS Every Lubrication point

20 hrs. or 400 km (250mi)

40 hrs. or 800km (500mi)

80 hrs. or 1,600 km (1,000 mil

When necessary

Oil/Grease Brand name

Seasonally

ENGINE: Starter case

0

Oil pump control box

0

Pump drive cover

0

Oil in the oil tank

Aeroshell grease #7A or Esso Beacon 325 grease 0

Y AMALUBE 2-cycle oil

DRIVE: Secondary shaft and sl id ing sheave

0

Front axle housing

0

Light all-purpose grease

Shaft 1 and shaft 2 (Slide rail) Drive chain oil replacement

Molybdenum disulfide snowmobile grease

0 0

Gear oil API GL-3 SAE #75 or #80

Steering column lower bearing

0

Light all¡purpose grease

Steering column upper bearing

0

Motor oil

Steering links

0

Brake wire and stopper and brake lever

0

BODY:

-

Light all-purpose grease 0

Telescopic strut suspension

0

-2-

Esso Beacon 325 grease

NEW SERVICE PROCEDURE SECONDARY SHEAVE V-belt shim There are two V-belt shims between the fixed and sliding sheaves. By removing one or both of the shims when the V-belt is worn you can obtain the same reduction ratio (3.5:1) as a new V-belt.

--l~__ -2

Fixed sheave -

mm (0.0787 in) Sliding sheave

-----

V-belt width NEW: 31.6mm(1.24inl

V-belt

Spring seat

V-belt shim (2 pes.)

Spare V-belt shim

1. V-belt shim (2 pes.) -

2. Spare V-belt shim

2. When the V-belt width is further worn to 29.6 mm (1.17 in): Remove both two shims.

3. When the V-belt width is further worn to 26.0 mm (1.02 in): Replace the V-belt with a new one and install the two shims.

1. When the V-belt width is wron to 30.6 mm (1.20 in): Remove one shim.

NOTE: _________________________ The removed shim can be reused when the V-belt has been replaced, so it should be stored between the sliding sheave and spring seat.

-3-

2.

WARNING:

Loosen the four engine mounting bolts.

3. Adjust sheave guage to the specified

When replacing the V-belt, be sure to install the two shims and check to see that there is a 2 mm (0.0787 in) clearance between the fixed and sliding sheaves. If no shims are installed, the clutch-in rpm will drop; this may cause the snowmobile to lurch when the engine is started.

standard sheave distance. By moving the engine back and forth, adjust the sheave distance so that the center-tocenter distance between the primary sheave mounting bolt and secondary sheave mounting bolt is equal to the specified standard sheave distance.

Clutch alignment To achieve clutch alignment, both the sheave distance and sheave offset must be properly adjusted. When they are properly adjusted, the clutch can function correctly.

Standard sheave distance: . 270 ~g mm (10.63 ~g.11 in) 1. Sheave gauge

Standard sheave offset: 11 Âą 0.5 mm (0.433 Âą 0.0196 in) Tool name

Tool No.

Sheave gauge

YS-91047

4. Adjust the thickness of shims on both ends of the secondary sheave so that the distance (offset) between the primary fixed sheave and secondary sliding sheave is equal to the sheave gauge.

1. Sheave distance 2. Sheave offset

1. Removing the V-belt a. Turn the secondary sliding sheave clockwise when facing toward the chain housing, and push the sliding sheave. b. When the sliding sheave is pushed, it separates from the fixed sheave so that the V-belt can be removed from the fixed sheave side.

-4-

NOTE: _________________________

SUSPENSION

• When the sheave distance and offset are properly adjusted, the sheaves are in contact with the sheave gauge at the four points as illustrated.

• The secondary sheave mounting bolt should be tightened to the following specification.

Front stopper band setting

Tightening torque: 60 Nm (6.0 m- kg, 43 ft-Ib) • Select proper shims to be used at A and B. The total clearance at A and B should be 1.0 mm (0.4 in) or less.

1. Stopper band

CD

No.5 No.4 No.3 No.2 No.1 (STD) No.O 1. Stopper band

It = 1.0 mm) 90201-222FO (t = 0.5 mm)

90201-25526 It = 2.0 mm) 90201-25527 (t = 1.0 mm) 90201-252F1 It = 0.5 mm)

5. Repeat steps 3 and 4 above until the sheave distance and sheave offset are adjusted correctly.

6. Tighten the engine mounting nuts while taking care not to move the engine.

Tightening torque: 52 Nm (5.2 m o kg, 37 ft-Ib) 7. Install the V-belt.

-5-

Snow condition

Hard packed

Soft deep snow

Length of stopper band

Track side slip

Performance of straight running

Bumping and pitching

Riding comfort

Lower (No.5)

Increase

poor

Less

Poor

Std. (No.1)

Normal

Normal

Normal

Normal

Higher (No. 0)

Decrease

Good

More

Good

Lower

Increase

Good

-

Poor

Std. (No.1)

Normal

Normal

-

Normal

Higher (No. 0)

Decrease

Poor

-

Good

Shock absorber spring adjustment Screwing in the spring seats on the front and rear shock absorbers shortens the spring set length, thus making the shock absorbers hard.

Screwing them out softens the shock absorbers. Adjust, as required.

'-~---------Spring

set l e n g t h - - - - - - - -...-~I

I~:~~:":"'::::~::::::::::=~=====":'.:A

7Shock absorber

~ Std. spring set length

Spring

Front shock absorber

Rear shock absorber

196 mm (7.72 in)

269 mm (10.6 in)

Spring seat

-6-

Lock nut

1. Front shock absorber spring

----Spring set length

STIFFER

4

.

Mini.

184 mm (7.24 in)

~

~

SOFTER

~

Max. 200 mm (7.87 in)

Track side slip

Hard packed performance of straight running

Deep snow

Handling

Increase

Good

Increase

Poor

Poor

Good

Decrease

Poor

Decrease

Good

Good

Poor

2.

~

Riding comfort

Rear shock absorber spring

------

Spring set length

STIFFER Mini.

269 mm (10.6 in)

s~

. â&#x20AC;¢

~

~

SOFTER Max. 269mm (10.6 in)

Handling

Track side slip

Performance of straight riding

Riding comfort

Heavy weight rider

Increase

Poor

Decrease

Good

Good

Poor

Decrease

Good

Increase

Poor

Poor

Good

-7-

SPECI FICATIONS A. General Model

SR540H

Model: Model (I.B.M. No.) Frame I.D. & Starting number Engine I.D. & Starting number

SR540H (8V9) 8V9·060101 SA535-060 101

Dimension: Overall length Overall width (Std.) Overall height (W/windshield)

2,675 mm (104.3 in) 1,080 mm ( 42.5 in) 970 mm ( 38.2 in)

B. Engine Model Description: Engine type Engine model Displacement Bore x Stroke Effective compression ratio Starting system Ignition system Lubrication system

SR540H Axial fan cooled two-stroke, torque induction, twin cylinders SA535 535 cc (32.65 cu.in) 73 x 64 mm (2.874 x 2.52 in) 6.0: 1 Recoil hand starter C.D.1.

"Autolube" oil injection

Cylinder head: Combustion chamber volume (with spark plug) Compression chamber type Head gasket thickness x Q'ty

25.5 cc (1.68 cu.in) Dome + Squich 0.5 mm (0.02 in) x 1 pc.

Cylinder: Material Bore size Taper limit Out of round limit

Cast iron sleeves aluminum 73 mm (2.874 in) 0.05 mm (0.0020 in) 0.01 mm (0.0004 in)

Piston: Piston skirt clearance (measuring point) Piston oversize Piston pin outside diameter x Length

0.055 ~ 0.060 mm (0.0022 ~ 0.0024 in) [17 mm (0.67 in) from piston skirt end] 1st 73.25 mm (2.884 in) 2nd 73.50 mm- (2.894 in) I/J 20 x 56 mm (I/J 0.787 x 2.20 in)

Piston ring: Piston ring design Ring end gap (installed)

Keystone 0.2 ~ 0.4 mm (0.008

Small end bearing: Type

Needle bearing

Big end bearing: Type

Needle bearing

Crankshaft: Crankshaft assembly width (A)

200 ± 0.25 mm (7.87 ± 0.010 in)

~

0.016 in)

Crankshaft assembly width (F)

60+0 mm ( +0· _ 0.05 2.362 _ 0.002'")

Crankshaft deflection (D)

D-1: 0.03 mm (0.0012 in) D-3: 0.04 mm (0.0016 in)

-8-

D-2: 0.04 mm (0.0016 in) D4: 0.05 mm (0.0020 in)

SR540H

Model Connecting rod big end side clearance (C) Connecting rod small end deflection (P)

0·,

97mm

Crank Crank Crank Crank Crank Crank Crank Crank

C

QI-

I

0.25 - 0.75 mm (0.010 - 0.030 in) P 2.0 mm (0.079 in)

0-2 0-3

0-4

"93mm

if> 24 x 59 mm (if> 0.945 x 2.323 in) Solid shaft assembly type with serration #6306 special x 2 pes. #6206 special x 2 pcs. #6206 special x 1 pc.

FWJ-32 789.5 TS x 1 pc.

Labyrinth seal x 1 pc.

FWJ-3248 10-1 TS x 1 pc.

pin outside diameter x Length pin type bearing type (left) x Q'ty bearing type (Center) x Q'ty bearing type (Right) x Q'ty oil seal type (Left) x Q'ty oil seal type (Center) x Q'ty oil seal type (Right) x Q'ty

Cooling fan: Fan belt tension

4 - 6 kg/8 mm (8.8 - 13.2 Ib/0.31 in)

Carburetor: Type & Manufacturer/Quantity I.D. Mark Main jet (M.J.) Main air jet (M.A.J.) Power jet (Pw.J.) Power air jet (Pw.A.J.) Slow jet (S.J.) Slow air jet (SAJ.) Pilot screw (P.S.) Starter jet (St.J.) Float height Idling engine speed

BD44-38/KE I HI N/1 pc.

8R601 #150 #180 #150 #170 #92 #100 2.0 turns out #160 12 - 17 mm (0.47 - 0.67 in) 1,500 r/min

Main jet setting chart

~ Altitude

-30 o e (_22°F)

_20 o e (--4°F)

I

I

Sea level

f---#155 - 600 m (2,000 ft) f---#150 - 1,200 m (4,000 ft) 1---#145 - 1,800 m (6,000 tt) 1---#140 - 2,400 m (8,000 ft) f---#135 - 3,000 m (10,000 ft) f---#130

.

.. ..

..

_1O o

e

(14°F)

..

#150

,..

-9-

I

I

~

#130

#125

.

#145

,..

.

200e (68°F)"

. .. .. .. . . .. ..

#140

.. ,.. .

100e (50°F)

I

I

..

oOe (32°F)

#135

.

..

#145

#140

#135

#130

#125

#120

Model

c.

SR540H

Intake reed valve: Type Bending limit Stopper height

V type 0.6 mm (0.024 in) 12 ± 0.2 mm (0.4724 ± 0.0079 in)

Lubrication: Autolube pump - Color code Autolube pump - Minimum stroke Autolube pump - Maximum stroke Autolube pump - Reduction ratio Autolube pump - Output Min.l200 strokes Autolube pump - Output Max.l200 strokes Autolube pump wire free play Oil tank capacity Oil grade

Green 0.20 - 0.25 mm (0.0079 - 0.0098 in) 1.65 - 1.87 mm (0.0650 - 0.0736 in) 1/36 0.95 -1.19 cc (0.0321 - 0.0402 oz) 7.84 - 8.89 cc (0.2651 - 0.3006 oz) 25 ± 1 mm (0.98 ± 0.04 in) at idle 2.5 L (2.6 US qt, 2.2 Imp qt) Yamalube 2-cycle

Drive and track suspension Model

SR540H

Transmission: Type Drive ratio Engagement rpm Shifting rpm Primary spring: Part No. Color code Secondary spring: Part No. Color code Secondary spring pre·load (twist) Sheave distance

V-belt automatic centrifugal engagement 3.5: 1 ~ 1 : 1 3,500 - 3,900 rpm 6,800 - 7,200 rpm 8U7-17643-00 Silver - Red 90508-50571 Pink 30° (No.1)

270~~ mm(10.63~g.11 in) 11 ± 0.5 mm (0.433 ± 0.020 in)

Sheave off-set V-belt width and outer line length V-belt wear limit

31.6 x 1,099 mm (1.24 x 43.3 in) 26 mm (1.02 in)

Track suspension: Type Damper type Spring color code (Front) Spring color code (Rear) Slide runner wear limit Track width Track deflection Length on ground Wheel sprocket material and number of teeth Stopper band length (Front) Stopper band length (Rear)

Slide rail suspension Oil and gas damper No painted No painted 10 mm (0.394 in) 381 mm (15 in) 25 ~ 30 mm/10 kg (0.98 ~ 1.18 in/22 Ib) 902 mm (35.5 in) Double polyethylene 9 teeth 250 mm ( 9.84 in) (No.1 hole from the bottom) 267 mm (10.43 in) (No.1 hole from the bottom)

Secondary drive: Type Reduction ratio Chain pitch x Number of links

Chain (#35-3) 17/31 (1 : 1.824) 9.525 mm (0.375 in) x 66L

Free play

+ 0.2 .ln ) 10 _+ 52 mm (0 .4 _ o.oa

Chain housing oil quantity Chain housing oil grade

250 cc (8.5 oz) Gear oil API "GL-3" (SAE #75 ~ 80)

-10 -

Model Brake: Type Brake pad thickness Brake pad wear limit Brake cable "L" distance Clearance between lining pad and disc

SR540H Floating disc type 5 mm (0.20 in) 1.0 mm (0.04 in) 57 mm (2.24 in) 0.15 - 0.3 mm (0.006 - 0.012 in)

D. Chassis Model Frame: Material

SR540H Aluminum + Steel

Steering system; Caster (ski column) Chamber Ski length x Width x Thickness Ski stance Ski toe-out Steering linkage type Steering angle Lock to lock angle (Ski)

25° 0° 980 x 120 x 2 mm (38.6 x 4.7 x O.OB in) 880 mm (34.6 in) o mm (0 in) Tie-rod Right: 46° Left: 46° L: 27.9° R: 33.4° Right ski L: 33.4° R: 27.9° Left ski

Front suspension: Type (YAMAHA T.S. SUSPENSION) Damper type

Coil spring Oil and gas damper

Fuel tank: Capacity Fuel grade

26.6 L (5.9 Imp gal, 7.0 US gal) Regular gasoline

E. Electrical Model Ignition system: Type - Flywheel magneto (C.D.I. Type) Model/Manufacturer Voltage Charging coil resistance Pulser coil resistance Ignition timing: B.T.D.C. Ignition coil: Manufacturer/Model/Quantity Spark gap Primary winding resistance Secondary winding resistance Diode (Yes or No) Spark plug: Type & Quality Spark plug gap

SR540H

F3T352/MITSUBISHI 12V 1,29012 ± 10% at 20°C (68°F) 1712 ± 10% at 20°C (6BoF)

(Brown - Black) (White/Red - Black)

1.5 mm (0.059 in), 15° at 7,000 r/min

i

HITACHI TOYO·DENSO I CM62-21 /1 pc.

I YW-51/1 pc.

I 9 mm (0.4 in)/300 rpm I+11 mm (0.6 in)/3,000 rpm: +0.15n ± 10% at I 0.12n ± 10% at 20°C (68°F) : 20°C (6BoF) 3.5 kn ± 10% at 4.0 kn ± 20% at 120°C (6BoF) 20°C (68°F) I I+No

i

NGK BR9EV x 2 pcs.

0.7 - O.B mm (0.028 - 0.031 in)

-11 -

SR540H

Model Spark plug cap: Type Noise suppressor resistance

Resign type with noise suppressor 5 kn ± 20% at 20°C (68°F)

C.D.1. unit: Model/Manufacturer

8N4·20/M ITSUB ISH I

Lighting system: Lighting output Lighting coil resistance Headlight type Bulb wattage/O'ty Tail/Brake light wattage Grip heater coil resistance

12V·l00W 0.19n ± 10% at 20°C (68°F) (Yellow - Black) Halogen light 12V -60/55W x 1 pc.

12V-8W/23W 0.66n ± 10% at 20°C (68°F) (Yellow/Black - Black)

A.C. regulator: Model /M anufactu rer Voltage

TRIZ-50/HITACHI or S85 16B/TOSHIBA 13.8 ± 0.5V

F. Tightening torque Part to be tightened Engine: Spark plug Cylinder head Cylinder Flywheel magneto Crankcase upper and lower: Tightening sequence:

Tightening torque

Thread size

First Final First Final

I

M14 M8 M8 M16 M8 M8 M6 M6

Pl.25 Pl.25 Pl.25 Pl.0 Pl.25 Pl.25 Pl.0 Pl.0

~~

6

7

8~~5

~3

1.

Nm

m'kg

ft'lb

28 25 25 73 10 20 5 10

2.8 2.5 2.5 7.3 1.0 2.0 0.5 1.0

20 18 18 53 7 15 3.5 7

·2 4'-

Remarks

/ -$-10

~9

11

~

Ring weight and stay Flywheel magneto and stay Fan shaft and pulley 2 Starter pulley Crankcase and engine bracket Drive and track suspension: Primary sliding sheave and cap Installation of primary sheave: Initial Loosen once and retighten Installation of secondary sheave Bearing housing Brake caliper and housing chain Installation of drive chain sprocket Installation of driven chain sprocket Chain housing and frame Installation of front axle L.H.

M6 M8 M16 M8 M8

Pl.0 PloD Pl.0 Pl.25 Pl.25

10 15 43 23 23

1.0 1.5 4.3 2.3 2.3

7 10.8 31.1 16.5 16.5

M6

Pl.0

15

1.5

10.8

UNF UNF M14 M8 Ml0 M20 Ml0 M8 M22

1/2" 1/2" Pl.5 Pl.25 Pl.25 P1.0 Pl.25 Pl.25 Pl.0

120 65 60 23 48 60 48 23 85

12 6.5 6.0 2.3 4.8 6.0 4.8 2.3 8.5

87 47 43 16.5 35 43.5 35 16.5 61.5

-12 -

Use Loctite® Use Loctite®

Use motor oil

Part to be tightened Front axle housing and frame Front pivot shaft Rear pivot shaft Rear axle Sliding runner Chassis: Engine mounting bolt Steering column and gate Steering gate Steering relay rod adjusting nut Steering lower bracket Installation of steering column 1,2 Steering relay ass'y Front shock absorber and bracket Bracket 1 , 2 set bolt Front arm Ski installation

Thread size MB M10 M10 M14 M6

P1.25 P1.25 P1.25 P1.25 P1.0

M10 MB MB M10 MB MB M10 MB M6 M10 M10

P1.25 P1.25 P1.25 P1.25 P1.25 P1.25 P1.25 P1.25 P1.0 P1.25 P1.25

-13 -

Tightening torque mokg ftolb Nm 23 64 BO 2.5

2.3 6.4 6.4 B.O 0.25

16.5 46 46 5B 1.B

52 23 14 47 23 14.5 47 21 2 16 43

5.2 2.3 1.4 4.7 2.3 1.45 4.7 2.1 0.2 1.6 4.3

37.6 16.5 10

64

Remarks

Use lock washer

34 16.5 10.5 34 15.2 1.4 11.6 31.1

Use lock washer Use cotterpin

Wiring diagram

Tac~ometer (12V 34WI

light

~

speedometer light

Color code L ......Blue Y ......Yellow O ......Orange G ......Green Br......Brown R ...... Red

.

~

Oil caution light

---H=:;-::-~~..j[5:J (12V 3.4WI

(12V 3.4WI

'B · ......Black · G/Y · ... GreenIYellow · B/R .... Black/Red B/W ....Black/White W/R · . .. WhoIte/ Red Y/B · . .. Y ellow/Black

Opt. (Grip heaterl

~Q

rl1t~~=±--~-=1-=-=1~-=-=-=-=-=-=t-=-=-== -==tt======t========J B Y/B

GIVB

L

G~Y ~L B

B

I

I

.....

.j>.

I

o-D::::J-O G/Y G

B/R

Ignition coil

C.D.\. unit C.D.\. ~agneto

Oil level switch

(12V. LR)W/23WI Tail/brake light Y B