Classic Dirt Bike Issue 34 Preview

Top UK Team

Brits win at the Vets des Nations

Dirtbike classic

#34

Issue thirty-four

Spring 2015

STARMAKER hI-tech two-Stroke deSIgned to take vIllIerS to the top

FULL CIRCLE Why Vic Allan went back to his roots and built a Dot 360

PlUs

CZECH MATE

How a return to MX turned up this unrestored CZ two-stroke

LAMPKIN TOP OF THE WORLD //HONDA XR200R //NORBSA NORBSA MX //HOW TO SAVE WEIGHT

On the cover Just because Villiers supplied most of the smaller makers with engines didn’t mean its own designs stagnated. With an eye ďŹ rmly on the future it developed the Starmaker power unit in different capacities to suit the scene.

A regular at the Vets MX d’Nations at Farleigh Castle, Doug Dubach, is as enthusiastic a racer as he was when crisscrossing his native USA in the beginning of his race career. Nick Haskell was at the Vets.

5

Contents 03 In balance

48 Dirt products

06 News, views and reviews

52 Dicko’s view

The view from the sharp end of classic off-road, we’ve been out there getting dirty and taking in the scene.

If it’s happened, happening or just happened in the off-road world then this is the place to find out about it.

16 Subscribe! Subscribe! Subscribe!

Have your favourite off-road sports mag drop on your mat as soon as possible.

18 Original and unrestored

We thought there would be a finite number but there are still unmolested dirt bikes like this CZ out there.

22 Something special

Mixing and matching is commonplace in the off-road world, though a Norton engine in a BSA frame is unusual.

34 You need…

… a Dave Curtis Matchless, except you can’t get one. However, you can drool over the pics.

Got something for the off-road world?

Tell us about it and we’ll tell the world because they need to know y’know.

It’s easy reckons our columnist. What is? The simple solution to falling trials entries, make them rideable and encourage people to ride.

61 Smith tales

It is mostly human nature to want to fit in with your fellows in whatever you do, there are those who take this to extreme degrees though.

72 Dirt talk

Got an opinion? Have your say, tell it like it is, this is the place for discussing all that’s going on or even gone on in the off-road world.

82 Moto memories

Now apologies for it being a bit of a Bultaco fest this issue, as Martin Lampkin being crowned world Champion is a momentous thing to celebrate.

Events 54 The sporting world

There are so many great events going on in the off-road world, we can’t get everywhere, though we do try. Here’s a couple we’ve been to.

62 Show time

Hot on the heels of the Carole Nash Classic Motorcycle Mechanics Show came the International Dirt Bike Show.

We were at both.

How to 44 Rebuilt to ride

Motorcycle sport is expensive, but it is possible to ride on a budget. We set out to prove it with a pile of Triumph bits.

50 Tech Talk

‘Lighter than last year’s lightest ever model!’ but what if that’s not light enough? We explore titanium fasteners.

Features 10 Is bigger better?

Dot tried it with the 360 engine introduced in 1965. Vic Allan raced against them in the day.

26 That was the year…

…that Martin Lampkin became the first official world trials champion. We take a look at that momentous year… 1975.

37 Packing a punch

Honda’s XR200R is a civilised, mild mannered, almost docile ride-to-work or

trail machine… it can also cut it at the sharp end of enduros.

66 An hour with…

…Gordon Blakeway, the star all-rounder who proved you can enjoy high level success and enjoy yourself too.

76 Stars in their eyes

Villiers was the mainstay of small engine production for the UK industry.

Didn’t mean the company didn’t have ideas of its own though.

Dot Feature Name Scrambler 10

A bright sunny day and a bright motorcycle waiting for its rider and action.

What might have been A desire to finish on a bike that he started out on, set Vic Allan on track to build a Dot MXer. Nick Haskell was on hand to capture the first real ride.

Words Vic Allan Pics Nick Haskell

D

ot motorcycles was started in 1903

by Harry Reed, a successful racer of his own make, using four-stroke engines from the period. Not until 1928 were the first of the Villiers engines used for a production motorcycle and they were built by Dot Motors Ltd with the famous (or infamous) slogan Devoid of Trouble being introduced in 1922.

Burnard Scott Wade took charge of the Dot name in 1932, but it would take until 1949 to start production of his own designed lightweight motorcycle road bike and a year later to introduce the Dot Scrambler.

Vic Allan takes up the story. “By 1957 my brother Robbie was ready to start competing and had a Dot as his first competition bike bought from Joe Furneaux, the Aberdeen dealer. Being mad about bikes from an early age, we knew all about the exploits of Bill Barugh in establishing Dot as the bike to have for the lightweight races.

“By 1961, I had officially become old enough to have a competition licence and eldest brother Jimmy let me use his Dot. When Robbie went to Greeves, which had

started the decline of Dot in 1958 with its success, I was still a loyal brand Dot rider.

“Scottish Championships should have followed in 1963 and 1964 but lack of mechanical knowledge meant I had to wait until 1965 before this peak was reached by one of the three Allan lads. With results against good English riders like Tommy Reynolds, who was a long standing Dot rider, it was felt a ride at the 250cc British GP at Glastonbury would be a logical move. With no experience of British Championship races, this was a huge leap to top level scrambling and Burnard Scott Wade invited us to the factory to have the bike fettled before the event.

“Four people in a Mini van with a trailer on the back set out for Manchester. Once there we had to leave the bike, then collect it again in a couple of days. Blackpool here we come, was just part of this adventure and we slept in and around the van as it was the best we could do with our meagre budget for such a trip.

“The bike was picked up from Manchester after the bill was paid and Burnard Scott

Wade said he would attend the GP. Expecting a great power boost did not appear to happen but it might have been a bit better.

The people on the gate could not understand our accent and thought we might be the Russian contingent. Race one arrived and being part of such a great event was like a dream come true, but no one had ever thought about signalling race positions in Scotland as the races were never that long and you just about knew what position you were in the race anyway.

“All I remember is getting a reasonable start and just riding as hard as possible. The last lap I turned round and saw a Union Jack on the rider’s bib and after 40 minutes the first thing that came into my mind was that I must be getting lapped. I moved over and let the rider through and another one came past at the same time. When I came into the paddock they asked why I had moved over and let Freddie Mayes through as he was behind me and not lapping me and I had therefore dropped from ninth to 11th for my first GP race.

“It was more than I ever expected and Mr

Vic Allan wanted to ďŹ nd out what the big Dot scramblers were like, so he built one.

Feature Name 18

Original & unrestored

1973 CZ 250 MX It started off as a nice idea when CDB was offered a totally original FrancisBarnett trials bike to feature. How many other comp bikes had survived unrestored, we asked, can’t be many surely? Maybe we’d get three or four out of the idea… seems there are more survivors out there than we thought, we must be at the limit now…

Words: Tim Britton

R

iders drift away from competing in motorcycle sport for perfectly valid reasons, generally involving lack of time due to work or family commitments, equally they drift back to the sport for just as many valid reasons. In Hugh Weston’s case, his son was the catalyst to his own renewed interest.

As he got involved with motorcycles again, Hugh thought, ‘d’you know what, I’d forgotten how much I like this sport’. A visit to the Farleigh Castle Vets meeting further confirmed his resolve to ride again and all that was needed now was a bike. This minor detail was actually solved by the Classic Dirt Bike online classified ads when Hugh was surfing the site one evening.

What appeared on screen was a CZ MXer in a bit of a state; the price was right, and the deal was done with the original owner, John Keane. He had laid the bike up after he’d last raced it in 1978 and as such it is a reflection of what was being raced at that time.

What Hugh bought is a 1973 250cc CZ motocross model with the designation 980.7.

While pretty much as raced, it isn’t quite original, but has had a little bit of updating.

Gone is the boxy steel petrol tank it would have originally worn, replaced instead by an alloy one from a BSA B50, a popular mod in the day and maybe done to save a little weight, but perhaps because it looked a little better to some eyes. Also changed is the front mudguard – it would have been steel too but luckily an American called Preston Petty was working away with plastic moulding

Exactly as last raced in 1978, Hugh intends to do the minimum to be able to safely scramble it.

and producing replacement parts that were better than the originals. Less obvious a modification is the bottom suspension mounting position, it’s been moved forward along the top of the swinging arm, making the units more upright in position.

With a reputation for utilitarian basic transport machines, CZ, had nevertheless made a good showing in events like the International Six Days Trial of the 1950s where its motorcycles proved tough enough.

They still had a way to go to catch the public eye at least in the UK. This was to change in the 60s when first, Joel Robert, then Viktor Arbekov and Paul Friedrichs earned world championships on the Czech machines.

To digress slightly, the motocross world was changing in the 1960s and two-strokes from all nations were being developed to produce unheard of amounts of power. Allied to inherently light weight, the resulting machines

were easy to ride and phenomenally fast.

In CZ’s case it had begun by developing an MX model out of its ISDT machines and tried out many features which would come to typify the marque in the 60s. Such things as twin exhaust ports and matched systems with early expansion technology which though not brilliantly successful at first, eventually propelled the company to great success.

The bikes also altered the rules of MX and brought in the minimum capacity restriction for 500cc class events. When CZ won the Czech 500cc event with an overbored 250, there was panic that other makers might just do the same, so the FIM stipulated a 300cc minimum engine displacement and CZ began work on a bigger motor.

Meanwhile, Belgian Joel Robert was at the start of his dominance of the 250 class with his CZ. The factory was quick to turn the works bikes of that time into production

Hugh Weston Admitting to be ‘nearly 50’ self employed carpenter Hugh Weston is a returnee MXer after several years away from the sport. He was involved in the early years of schoolboy motocross from the age of 13, riding a Mohican Zundapp, with the Horsham Schoolboy Scrambles Club.

Hugh Weston, all fired up about scrambling again.

In the adult ranks Hugh raced Kawasakis, first a 125, then a 250, with Portsmouth and the Southern MX Club. He cites his mum as being very supportive during this learning curve and supplying the first bike – a BSA Bantam in trials trim.

In answer to CDB’s trick question ‘what’s your favourite bike of all time?’ he hardly had to think about it as he said: “Kawasaki’s KX125A5 from 1979, it’s what I raced and it’s a great bike.” He added there is a KLX250 in the shed awaiting a rebuild too.

Honda Feature Name XR200R 38 Not so with the XR200R – even my other half commented on how I seemed to gel with it. Yes, this bike is built for ‘go’ and boy can it go! Don’t get me wrong here as it’s no fire breathing monster determined to paw the sky at the slightest tweak of the twistgrip, in fact it is remarkably civilised compared to some things I’ve ridden, just it has hidden depths. Not only is it capable of carrying the owner to and from work during the week, or even taking a pillion passenger on a gentle trail ride in the most mild mannered and civilised way, but like Clark Kent slipping into a phone booth, the XR200R can shrug off the meek façade and mix it with the big boys in a tough world.

Upgrading

In keeping with the ‘you meet the nicest people on a Honda’ then the Japanese maker produced a mild mannered 200cc ohc enduro machine for the masses. It was popular in the USA where there were still loads of places to ride, it was popular in Europe where the trail type motorcycle was more accepted than the racer type and it began to enjoy increasing popularity in the UK as the trail scene started to grow.

Typically Honda, it did what it said it would do, did it reliably and almost unnoticed as supposedly superior machines earned reputations as a bit intimidating. The Honda on the other hand was everyone’s friend.

Naturally a few people felt the Honda could

do better and did a bit of work with it to improve matters, then Honda had a look at it and improved it in their way.

Not for them the highly tuned engine route, no, the wet sump, ohc single was okay as it was, no fuss, no problems, no temperamental high strung quirks just bomb proof reliability and easy starting. Instead Honda added the motocross developed Pro-Link rear suspension and suddenly every little bit of the engine’s power could be used to the full.

If you’ve not had a look at the Pro-Link rear set-up or any single shock system for that matter, there is an inherent weight distribution on most of them over conventional twinshock systems. Basically the weight is at the top of the damper unit on all but the Pro-Link which mounts the pivot point under the engine, smartly lowering the centre of gravity. This in itself would be advantage enough, but Honda also engineered it to be progressively rising rate.

A perfect system then?

Not exactly but pretty close, for instance, where the air filter would normally be there’s a large spring, so Honda had to get creative with the airbox and those linkages don’t like dirt. That’s not a criticism of the Honda linkages but a reference to any linkage regardless of who made it. Twinshocks tend to have a rubber bung with a steel bush inside it for a bolt to pass through as a mounting point. The linkage system

Specification Engine.................................sohc single Bore x stroke ................66.5 x 57.7mm Capacity .....................................195cc Ignition ...........................................CDi Gearbox .................................six-speed Frame .................steel tube with engine as stressed member Suspension front .................air assisted telescopic 9.8in travel Suspension rear ..............Pro-Link single shock 9.2in travel Brakes.....................front and rear drum Front wheel ......................3.00in x 21in Rear wheel .......................4.00in x 18in Dry weight ...................................222lb

It’s no fire breathing monster, in fact it is remarkably civilised compared to some things I’ve ridden, just it has hidden depths.

Small drum brake, small bike... it works well, a tie-wrap keeps the cable in place.

The Hot Trod Enduro weekend experience Making up a weekend of enduro sport, Hot Trod comprises a Hare and Hounds on Saturday afternoon and then a traditional time card enduro on Sunday.

Regular enduroistas can skip this bit but, if you’re new to it like I was a couple of years ago, the Hare and Hounds consists of two one hour sessions separated by an hour rest period – the idea is to ride as many laps of the laid out course as possible in each hour.

A time card enduro is much more involved and each rider is issued with a start time and a duration time for each lap and it is their responsibility to work out their times for each period. After each lap the bikes are held in a parc ferme and any maintenance can be done by the rider. The competitor can’t start before the specified time.

In such boggy conditions as this, it is best to keep going as getting stuck is exhausting.

Rather than alter an existing engine, Honda redesigned speciďŹ cally.

Everything neatly in place, nothing sticking out to catch on the undergrowth.

Feature Starmaker Name Metisse 76 76

Starmaker Metisse

By christening it ‘Starmaker’, Villiers left no doubt about the possibilities for anyone using its new engine and when allied to a proven MX chassis… the sky’s the limit.

Pics Joe Dick Words Tim Britton

O

ne of the most regularly trotted out statements about the British motorcycle industry is how complacent it was with comments along the lines of ‘once they’d figured out how to make a piston rise and fall and convert that into forward motion that was pretty much it’.

This isn’t quite true, as it ignores all sorts of reasons for engineering decisions, design ideas and concepts. Rarely is anything designed or developed in a vacuum and lots of factors affect choices made by factory design departments. From the average size of a typical human who might want to purchase the motorcycle, to constraints of the materials available to the maker of the

time, many factors influence where the pencil is applied to that clean sheet of paper on the drawing board of a design department.

It’s not just physical constraints which affect design or development either. Take the multitude of taxation classes used since motor vehicles were invented and governments latched on to the idea they could charge a bob or two to those who wanted to use them.

Ever wondered why the tech spec of a big trial or enduro is called a ‘weigh-in’? The bikes were actually weighed in the early days to ensure they were in their correct class.

Add in the political decree that manufacturers must provide a 10 year spares backup for any vehicle they produced

and the fact that any development happened seems to be a triumph against adversity rather than a lack of ambition. Still, bikes were designed, bikes made and all obstacles were overcome at least to the best of the conditions of the time.

One of the biggest makers of the time didn’t actually produce complete motorcycles but supplied engines to a multitude of people who did. Yes, you’ve got it… Villiers. The company’s two-stroke engines were produced in vast numbers and powered road and competition bikes for years. It was no idle boast the company could sell every engine it made and would hardly need to rock the boat by experimenting. Luckily the company employed people who kept an eye on the scene outside and strove to make sure engines were up to date or decide they’d reached their end.

One such chap was Bernard Hooper who had the feeling the Villiers 34A scrambles unit was on the limit. With more and more international makers going two-stroke, the 34A unit was being pushed to 22bhp, okay and a wee bit more, but Hooper realised the limit had been reached and wanted an engine that gave 25bhp at the outset. With the

Though still Starmaker, the engine has a DMW type of barrel with an extra port.

Lime green finish means it’s a Competition Classics-built bike from a small batch.

growing interest in lightweight motorcycles in competition, there was more understanding of the way a two-stroke worked and certain ideals were laid down for the new unit.

These started off with a desire for small crankcase volume, which in turn dictated full circle flywheels and close clearances.

However, before the flywheels could be created, the con rod needed to be determined, though it was actually a compromise here as for gas flow and oval shape is ideal but for strength an ‘H’ section is preferable. Hooper came up with an H section whose edges were feathered to aid gas flow. This shape meant a thin rod could be used and the flywheels could be closer together for improved rigidity.

In his article in The MotorCycle of February 1963, Bob Currie reported a lot of the concerns of using a two-stroke for a high performance application had been addressed to make the engine as unburstable as possible. From high quality steel used to forge the crank webs to needle roller bearings backing up roller bears on the crank and large diameter expander plugs in the crank pin, the new unit was clearly a serious attempt to put Villiers right at the top.

Koni classic dampers smooth out the rear end during scrambles action.

Light bike needs a light brake, thus saving weight and making the bike lighter...

Rarely is anything designed or developed in a vacuum and lots of factors affect choices made by factory design departments The designer had also taken note of the higher speeds an MX or scrambles engine was having to rev to in the mid 1960s and realising the lighter various components intended to spin could be made, the easier it would be for them to spin and the less stress they would have on the engine. Typically, a two-stroke engine is powered by an ignition system comprising flywheel spinning round and typically the Villiers one had been made of gunmetal – an alloy of copper, tin and zinc – and heavy. Hooper decided a light alloy flywheel would be less inclined to bursting at high rpm and the result was tested to 17,000rpm, a figure unheard of at that time for a British engine.

In order to continue the weight saving

ethos, the new unit had its head and barrel cast in light alloy, though the barrel had an austenitic iron liner. In case, like me, you don’t know what austenitic iron is, there are thousands of words written about it but for this feature it is a process to alter the structure of iron to make it more stable which means it expands at the same rate as the alloy of the barrel. If you’re a metallurgist, please only write in if you can explain ‘austenitic iron’ in 30 words or less.

Hooper determined the barrel should have widely spaced fins to reduce the chances of them clogging up in an event and he also put these fins as far into the cooling stream as possible. Introducing the fuel mixture to the engine and getting the burnt charge out is

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