WHATLIES WITHIN
KUHN COMMAN DO .............................6
Aprivate racing Norton whichcould beat the factoryCommando racers? Alan Cathcart remembers the Kuhn Nortons…
BULLETBOBBE R! ............................... 30
Is it anew engine in an old rigid frame? Is it afactory new modelorprototype even? And is it any good? Never one to ignore an interesting and unusual bike, our Odgie investigates....
BSAMODEL E....................................38
Sometimes, when youget an old bike going again, you’re restoring more than the machine’s mechanical components. Paul Henshaw explains…
TR IUMPHT120V BONN EVILLE .......... 46
Never much afan of oily-frame Triumph twins, Frank Westworth admits that this 1972 machine is alittle special…
ANORTONR IDINGLIFE..................... 54
Martin Richardson always dreamed of owning aDunstall Dommi. So he started accumulating Norton spares, and made some good friends alongthe way…
LIFE AMONGTHE AUCTIONS.............60
What happens in Las Vegas, stays in Las Vegas –unless it involves the world’s frst million-dollarmotorcycle.Corey Levenson rolls the dice on old bikesinSin City, while Rowena Hoseason looks at the auction action back in Blighty…
LAVE RDAALPINO ............................. 74
3
Do you remember the GusKuhn Commando racers? Only one of us in the RC ofce does… Andthenwehavea Beezer, aBonnieand aBobber –possibly the most remarkable reimagining of an RE single that we’ve every seen. And of course there’s lots more!
WE’VE GOTMAIL! ........................................ 14
Ah, your letters. Everything from battery care, bike stands and along, long time witha Commando…
READERS’FREE ADS .................................... 72
Couple of real lovelies here.Hang ontoyour wallets
LETTER FROM AMERICA..............................
Buying one non-running BSA might be considered normal. Buying two could be trouble. Buying four of the things…isthat a symptom of aserious medical condition? Kevin Lemire seeks medication
PUBTALK ..................................................... 82
PUB provides an illustrated review of BritishWD DR bikes supplied for WWII
OLLIE’SODD JOB ......................................... 88
Last time, Stu Thomson deconstructed a pair of Laverda’s dohc parallel twins.This time, he puts one of them back together again…
What does one do whenone has acustom Panther, and another custom-built Panther V-twin you need to moveabout? Well, it’s obvious, really, isn’t it? Ollie Hulme answers his own queries
TALES FROM THE SHED ...............................
Changing handlebars is easy,isn’t it? Frankfts some and fnds outfor himself…
WHO’S DONE WHAT
YOUR APRIL 2025 issue of RealClassic magazine wascompiled andconstructed in time -honoured fashion Frank Westworthand Rowena Hoseason of the CosmicBikeCoLtd Sanjayand Arun at Druck Mediaprime the page designwhile Mortons Media Group Ltd (01507 529529)managepublishing,trade advertising,your subscriptions,special ofers, merchandise and back issues.HappyEaster, ever yone!
READ MORE about old bikes at www.RealClassic.co.uk
TRADE ADVERTISERS forthe magazine or websiteshould call TomLee on 01507529413 or email TLee@mor tons.co.uk
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THIS MONTH we’vebeen reading ‘Politics on the Edge’byRor yStewart (an eye- opener abouthow little infuencejunior ministers actually have); ‘Ducati 748’ by Alan Cathcart (riding it on road and track); ‘Sword of Destiny’ by AndrzejSapkowski (because anew season of TheWitcher is due anyday!);‘OutOfThe Dark’ and ‘BornInFire’,bothbyMarkHenrick (allegedly grippingscifstuf),and ‘Blood Grove’,byWalter Mosley (a truly brilliantEasy Rawlins detectivestory)
MEANWHILE AT THE MOVIES we adored DETEC TIVE OF MING DYNAST Y(although Amazon’s translation algorithm really isn’t up to SkyNet standards); gloriedin the daftness thatisGuy Ritchie’s SNATCH; thought ELEVATION wasjust plain daft(aliens that can’t climb mountains?); gave aC- forefort to THE DARKEST HOUR (sparklyaliens invade Moscow!), and were somewhatstunned to discover thatthe ANGELT Vseriesisreally rather good.Ifyou like vampires and demons, thatis…
RealClassic is published monthlybyMMG Ltd, Horncastle,LN9 6JR,UK
FROM THE FRONT
Ever ysooften Ilike abike which Iactually ownsomuch thatIdecide thatIshould write about it,never mind simply riding it –orin factjust throwing spanners,hammers and invectiveatit, which is toooften the case Some bikes,Ithink,are greatasprojects.And when they ’vedone the whole projectbike thing and I’ve put afew milesontothe clock I wonder whattodowith them.
This is not as easy aquestiontoanswer honestly as youmight think.Imean, who buys abike purely forthe unreliable entertainment of rebuilding it –orsimply making it work decently well? Ido, as youmusthavenoticed by now. Alltoo often, Ican reveal only while whispering,the objectofmyenergies,efort and expenditureturns out to be abikeIdon’t actually enjoy riding very much. Strange but true.There aremanymoments of truth in the lifeofa project,times when it’s sensible to sit back,pour aglass of something (fzzywater is fne) and gaze realistically at the fruits of your expertattentions
This happens to me quitealot.Istar tout the bench business with fond hope thata fewmonths of spannering,research, parts hunting,morespannering and even more spannering will result in abike Isimply cannot wait to ride.And then… Andthen…
Well,then obviously Imake it road legal and set out onto the highways.Sounds easy, doesn’t it? It should be,ofcourse,but far too frequently abike whichhas alwaysstarted easily and consistently on the bench simply refuses to startatall when I’mtogged up and ready to braveboth climate and potholes.This happens alot.Would youlikeanexample?
OK.Takethe increasingly handsome BSA which has been absorbing my eforts forafew months now. It’s alwaysstartedeasily –oncethe fuelling hadbeen sortedout,a batterycapable of supplying the full twelveVolts had been ftted,and everything which needed tightening or taping down treatedappropriately.You know the routine: fuel on, tickle both carbs,kick acoupleoftimes,tickle again, switch on the sparklers and kick with vigour and application.
Correct. Thefrst time Idid thissothat Icouldenjoyafew tr y- outmilesthe bike star tedfne.Ileftitwhile Idonned the gear; helmet,gloves, winterdrawers and so on, then returned to repeatthe star ting routine It spatatmeacoupleoftimes but steadfastly refused to run. Why? Ihavenoidea. I’ve alwaysliked BSA’s unittwins,but my actual ownership experiences have toooften been less than fulflling.And of coursebythe time I’ddisrobed and replaced the Beezer upon
the bench it star tedfrst kick,thensat there idling smugly while Ijumpedabout cursing.I decided thereand then thatIwouldreplace its exhaust system fornosensible reason apar tfrom… Idon’t know what.
TheT120V Bonnie which graces our cover this monthisthe completeopposite. I’ve never much liked thatgeneration of Triumph twin, but wasgenuinely takenabackbyhow well this one works. Suddenly determined to provethatitwas like toomanyotherbikes in its unwillingness to actually provide areal, genuine riding experience, Iwentthrough my star ting routine,except thatthis time when Iwaddled from the house,dressed like the Michelin Manofold to combat the wintr y weather,itstar tedfrst kick,tickedoverwhile Irecovered from the shock,and thenran per fectly untilIremembered –ahalf- dozen miles from home –thatithad been running on reser ve when Iset out.Sometime ago Gentle reader,Ican reveal thatIfuelled up in nearby Holswor thy(not acheap under tak ing with the huge UK fueltank), and thatthe bike restar tedhot while interested par ties looked on hoping forfailureand embarrassment, and it has continuedto provide actual transpor teversince.
Of course Ineeded to writeabout this,soI have
Andride safely
Frank Westworth
Frank@realclassic.net
PACK AGE E
AprivateracingNor tonwhichcould beat the factor yCommando racers?
Photos by KelEdge
Alan Cathcar tremembers theKuhnNor tons…
Winning anyraceis always abig thrill,and winning achampionship run over severalrounds is deeply satisfying.But winning racesand amajor titleby defeating the factory team run by the company which built your motorcycle –especially if they’vegone out of their wayNOT to help you do so –must be the ultimatedream of any privateer team, even if so very rarely achieved. One of the handful of privateer equipes which pulled ofthisfeatin the upper
echelons of British National road racing downthe years wasthe London-based Gus Kuhn Nor tonteam, whose riders Dave Potter, Charlie Sanbyand beforethem Mick Andrew several times defeatedthe worksNor tons at both National and International level in Production and Formula 750 events in the 1969-1974 period.This wasthe heydayof big-bikefour-stroke racing in Britain, and the swan song of the Nor tonmarque as aforce to be reckoned with on the racing scene –until its triumphantreturntothe winners’circle
ffteen years laterwith the RC588 Rotar y racer. Yetthanks no doubt to their highprofle John Player sponsorship,aswell as the advanced natureoftheir various chassis designs,itwas alwaysthe factory Nor ton racers which grabbed the headlines, whereas quitefrequently,itwas the Gus Kuhn riders who actually led them home!
So in 1972, forexample,Gus Kuhn’s Dave Potter won17UKNational racesand was crowned British 750 champion on aKuhn Nor ton, defeating the factory John Player Nor tonteam to do so.Then, the following year he wonone of the Brands Hatchrounds of the UK vs.USA Transatlantic TrophyMatch Race series,and fnished 11th overall in the Imola 200 on the same bike,onceagain beating the factory Nor tonteam. Also in ’72, Potter and Graham Sharphad the satisfaction of getting aKuhnNor tonhome in 8th place in the gruelling Barcelona 24 Hours race after the worksbike of Williams /Croxforddropped out,tobethe frst to coax afast butfragile 750 Commando to the fnish of the Spanish marathon.
Andinraceafter race in the 1969/70 seasons,KuhnCommandos riddenbyMick Andrew,Charlie Sanby, Dave Croxford (later to become aJPN team member,ofcourse!) and PatMahoney swept the boardin British Production racing,frmly registering the name of the South London dealers as synonymouswith fast and reliable Nor ton roadster-based twins.Acer tainBarry Sheene even raceda Kuhn Nor tononceortwice, leading the 1970 Barcelona marathon after 15 hours beforethe gearboxbroke,but also fnishing thirdinthe Scarborough Gold Cup the same year on asimilar machine
Unsurprisingly,with their enthusiasm fuelled by this record of success on the track,the caféracer crowdofthe early ’70s queued up to buy Kuhn aftermarket par ts for their street Nor tons.This justifed the whole exercise in the mind of Kuhn boss Vincent Davey, whose companylater went on after Nor ton’sdemise to become one of the UK’s largest BMW dealers,and fora time in the ’70s they were also MV Agusta’s British impor ters.
‘Wewentracing to enjoyourselves,toput abit back into the spor t, and certainly to get publicityfor the business,but aboveall as amorale-booster forour staf,’ Daveytold me.‘ Theracing efor tengenderedaterrifc amountofteam spirit in the frm, which meantthatwenot only had ourpickofthe best people going,but we kept themlonger too, and this benefted the customer, which of course wasgood forbusiness.Our riders Mick Andrew and Dave Potter both star ted out work ing hereasmechanics beforethey began racing our bikes,and thatmeant
this spor tnewly impor tedfromAustralia could provide alucrativefuturecareer.Kuhn movedtoLondon to join StamfordBridge as Captain, and they wonthe frstSouthern League championshipin1929, but closed in 1932 –whereupon he transferredto Wimbledon, wherehestayeduntil 1937, winning ahigh propor tion of the raceshe star ted. He then did astintatWembley, beforebecoming Captain of the LeaBridge team. Gus Kuhn frst represented England in 1930 in the frst so -called ‘Test Match’ against Australia, and oftenrodefor his countr yinthe 1930s.Healso rode the Wall of Death, always actedashis ownmechanic and wasver y popular with both fans and fellowriders alike
Born in 1898 in Birmingham afterhis German grandfather had immigratedto Britain, Gus Kuhn ser vedin theRNVR and RFC during the First WorldWar,beforebecoming an early star of 1920stwo -wheeled motor spor t. As aLevisrider he wonthe frst Victor y Trial to be stagedin1919, andthe following
Even the powerplant looks unfamiliar from this side
year fnished seventh overalland second in the 250ccclass of the Junior TT.Herode further successiveyears in the Isle of Man withoutany luck,beforejoining the works Velocetteteam to fnish ffth in the 1926 Junior TT.
In 1928 Kuhn took par tinthe frst Speedway meeting to be held in the UK at High Beech, and as he nowhad awifeand four daughters to suppor t, he decided that ourefortsweredirectedtowards chaps who were already par tofthe family. It wasahappy team.’
In the 1930s Gus Kuhn had establishedhis ownmotorcycle business in South London, and in 1948 ayoung ex-Paratroop ofcer named VincentDavey joined the frmto manage it forGus,who had little interest in business.Davey duly fell forthe boss’s daughterMarian, and aftertheygot married went on to take the company to greater success as aNor tonmain dealer.Gus Kuhn passed away in August 1966, ironically while his daughterand family were away on the Isle of Manfor the Manx GP races.
Nor tonintroducedthe Commando in 1968, at the end of which year Gus Kuhn Motors began racing when VincentDavey found himself with some sparecash thanks to a compulsor ypurchase order served by the
TWOSIDES NOW
local council to build an old peoples’home on land he owned adjacentto the Kuhn workshop! Originally,the team contested the 350 and 500ccclasses with Seeley machiner y, as well as the 750 Production class with the Nor tons they were selling in thedealership –but then as big bike racingbecame more popular,Davey cut out the smaller classes and concentrated on the big twins.
Kuhn were one of the earliest entrants in F750 racing when it wasexported to Europe from the USA, furnishing Daytonawinner DonEmde with apair of Kuhn Nor tons for the1972Transatlantic series,eventhough their ownrider Dave Potter hadn’t been selectedfor the British team. By then, the team had developed aver ypurposeful F750 racer, employing Mark 3Seeley frames using several of their ownspecial par ts,and with Commando -based engines exper tly tuned by former AMCraceftter,Jim Boughen.
‘Wenever got anyhelp from Nor tons,apar t from somestandardpar ts freeofcharge in 1972-73,’recalled Davey. ‘I thinkwe
Obser ve thatnot onlyistherenoIsolastic mount,there’s very little frame tubery to hang it from
The gearboxisa 5-speeder from Quaife,while big pipes supplya bigfow of essential oil
The rider’s leftfootchanges gear, surprisingly,while the coveroverthe transmission has its ownrubber mountings
The entire unit is mounted rigidlyinthe frameand the right-side pedal operates the rearbrake
THEOPPOSITION
Nor ton’s1972 factor yracer,completewith its pannier fuel tanks; lowering the centre of mass isaracer’s priority
Alan Cathcart at the helm,putting the 1972 machine through its paces
were regarded as even moreofapain in the neck than the BSA/Triumph team, because especially afterthe John Player sponsorship came along,the Norton boys were under even greaterpressurenot to get beatenby another Nor toncrew! Iremember soon after theJPN team wasset up,webeatthem rather badlyata Cr ystal Palacenational in front of Dennis Poore, Nor ton’sboss,and allthe tobacco people.Poor Frank Perris,the JPN team manager,got told of in public by Poore forgetting beatenbyus, beforehedrove of in ahuf.Thatsor tofthing didn’t endear us to anyone in the Nor tonraceshop!’
SeveraldiferentSeeley-framed bikes were used over the years by the Kuhn team, being disposed of gradually as new ones replaced them, until by the last full season,1973, two bikesremained,each paintedthe distinctive Kuhn colours of green with awhitestripe These were both racedbyDavePotter– later to make his markriding TZ750 Yamahas for TedBroad,beforehis untimelydeath in 1981
The late andindeed greatPeter Williams in Nor ton’sworkshopatAndover with 1972 pannier-tankJPN
at Oulton Park.Both these bikes appear to have sur vived intact, one ending up in Nor thernIreland and the other,after being soldbyKuhn’stoScotland,and racedthere with some success fora number of years by Jock Findlay, wasthen acquired by my good mate Pete Johnson, asuccessful US Vintage and BoTT champion.
Pete had boughtitintending to keep the bike in Britain foruse on his frequentbusiness trips to Europe,but in view of his increased commitments in US competition, he’d only raceditin the UK ahandfuloftimes during his three years of ownership,beforehe phoned me up one summerafternoon from across ThePond.‘Please take it to Mallor yfor theday and blowthe cobwebs outfor me,’ he asked me.Happytooblige anytime, Peter… Likethe other Mark 3Seeley frames (the frst ones with no frontdowntube) employed by the Kuhn team over the years, chassis no.MK3 CS149N wasftted by them with a bolt- on ladder-type subframeconnecting
the front engine mounttothe headstock to provide added rigidityand suppor tthe rigidly-mountedengine better.During its time in Scotland,this wasremoved and the engine mountedfexibly using Isolastic mounts,presumably to countervibration. When RichardPeckett of P&M Motorc ycles, to whom Pete had entrusted the task of rebuilding the bike,strippeditout,the frst thing he did wastoreplacethe Isolastic rubbers with solid blocks to mountthe engine rigidly again, to stop it shak ing about all over the placewhen run. However, instead of the ladder-type subframe,which could only be bolted in placewhenthe engine wascoldand not adjusted subsequently to take heatexpansionintoaccount,heftted a single vertical strut with spherical bearings at each end thatcouldbeadjusted up to ensure correctlocation when the engine washot Nice –ifnot totally original
TheCommando-based Kuhn Nor tonengine wasrebuilt by the late Nor tonspecialist Mick
The frame’stop tubes andsteering head designare very reminiscent of the famous featherbed.The rest of the frameisrather diferent
Hemmings,who on stripping it found it was fttedwith oneofthe original works-typeAMA heads on which the big-valveconversionhe latermarketed forNor tontwins wasbased. This has are-angled, larger diameter 40.5mm inlet valve(38mmstandard) on each cylinder, but with original size33mm exhausts,with fully sphered combustion chambers.But the exhaust valves ftted were Nimonic forextra durability, and Mick also installed Carrillo steel rods instead of the standardalloyones ftted to the bike,which Jim Boughen usedto polish longitudinally
‘Weused standardvalvesprings and inlet valves when Idid the engines,’ recalled Boughen. ‘The big valves afectedtraction on shor tcircuits,and only showedupwell on fast tracks likethe Isle of Man. ButI’d stopped doing Kuhn’s engines by ’73,and they probably ftted the big-valvehead for theImola200, which wasaver yfast track back then.’
Hemmings installed anew set of Powermax pistons,skimmed the head 60 thoutoobtain 10.5:1 compression, and fexiblymounted the twin 32mmAmalMk.lConcentriccarbs
Instead of the pointsftted to thebike,he installed aBoyer electronic ignitionrunning of the 12V batter ypositioned under the vinyl fap in the distinctiveKuhn seat, while RichardPeckett had new moulds made forall thebodywork,and thus can supplyany par t seen on the bike to order,including thelargecapacityT Tfuel tank
A4Scamshaft, hottest of the Nor vil range, wasftted just as back then. ‘Weran a4Scam, points ignition and pulled thetiming back to 28 degrees,’ Jim Boughen told me.‘Lucas Rita electronic ignition wasjust coming in then, but it wasprettycrude,and not very dependable. We hacked alump out of the timing cover
Although there is no actual set of front downtubes,thereisa vertical strut to provide positive location of the engine
1970 SeeleyMk 3frame
on acoupleofengines to ft it,but went back to points afterwards as theredidn’t seem any advantage.’ Pete Johnson’s bikehad just such a partofits timing coverremoved…
Mick Hemmings sentthe Kuhn Nor ton crank to car restoration specialists Bassett Down Engineering to be dynamically rebalanced,ftted his ownbelt- drive conversion forthe 5-speed Quaifecloseratio gearboxtoreplacethe original triplex primar ychain, and retained the standard Nor tondiaphragmclutch ftted to the bike, nowofcourse runningdry
‘The reason it took us so long to fnish a24Hour race wasbecauseVincentDavey would insist on runningthatheavy oldNor ton clutch,’insisted Jim Boughen. ‘Iwantedto ft anicelightAMC racing unit which would
also have saveda bit of weightand alot of complication, buthewouldn’thaveit, so of course the transmission usually packed up after8 or 12 hours.’ No such problems in UK shor tcircuit racing wherethe Kuhn bike spentmost of its life, though, and the beltdrive conversion ofers muchgreater convenience, as well as increased durability. Slotted back into the Seeley frame freshly rebuiltby P&M, and with the bodywork repaintedinwhatone mighttermneo -JPN liver yrather than the original green Kuhn colours,the engine yielded Pete Johnson some enjoyable rides on the bike,ifnot alot of success compared to his 1987 win over Team Obsolete’sDaveRoper inthe USA’s AHRMAF750 Vintage championship,riding his P&M-built Triumph-3. My trip to Mallor y
wasasmuch to see if the bike could be sor ted out alittle better,astosample it formyself.
Having previously ridden theKuhn Norton’s greatrival during the 1972season, the pannier-tank John Player Norton that’sone of the four JPNs nowowned by Joaquin Folch in Spain, ftted with the same basic Commandobased engine,itwas agreat chanceto compare the twogreat early-’70s BritBike adversaries forthe crownofKingCommando.
Chassis-wise,itwas no contest: the Seeleyframed Kuhn bike wonhands down. Like on the JPN, the riding positionwas very lowand tight, so diferent thanonthe morespacious Seeley G50s I’ve ridden and onceowned, and almost certainly due to the big tankand shapely,cur vedseatyou sit in the bike,not on it.Eventhough 18-inchwheels were ftted frontand rear,and the twin rear Girling units were the long 12.75 inch ones,Ifelt as if the rear end wassquatting lowerthan the front, again like the ’72 John Player Norton I’dridden, although thatused a19-inch frontwheel
Butwhereas thatbike steered in aslow, laz yfashion thatwas stable on fast turns but far from agile on slowones, its Kuhn rivalhad fnely-balanced,neutral steering thatmust have made it ideal forthe hurlyburly of British shor t- circuit scratching.Over Mallor y’sbumps the Nor vil frontend and its sticky KR124A Dunlop tyre coped well,and exiting Gerardsthe powercould be fedin hardwithout the frontend understeeringas it does on so manybikes there. But the rear end hopped and sk ipped around quiteabit, almost certainly duetotoo stifspringing for my weight–that’sa nicechange!
Aftera fewlaps Ifound myself completely at home,enjoying the feel of sampling once again the chassis thathad to be the epitome
Conical rearhub holds the slsdrumbrake,and the chain adjusterslookmeaningful too
Dave Potter (Kuhn Nor ton) leadsRay Pickrell (Triumph-3)
DonEmde (Kuhn Nor ton) leads Dave Aldana (BSA-3) at Brands Hatch in the Transatlantic MatchRaces one month afterwinning Daytona 200 on aYamaha 350
of the black ar tof1960s British frame design, as honed to per fection by ColinSeeley and his men.Interestingly,itseemed to ‘talk ’ to the rider morethan Seeley frames do when ftted with Matchless G50 engines, which sometimes seem almost toostif and unforgiving compared to theless agile but moreforgivingstandardMatchless frame, and can sometimes step out on youwithout anyprior warning. Maybethe extraweight of the twin- cylinder engine made theKuhn’s frame moreresponsive, but it wasabikethat inspired confdence.
Thesingle 11.5in Nor vil frontdisc provided quiteadequate stopping power, even at Mallor y’swalk ingpacehairpin, especially allied withthe notable engine brak ing available from the lustyparallel-twin motor –though youmust take carenot to bouncethe valves on theover-run.And using just asingle frontdisc also reduces unsprungweight, to optimise suspension compliancefromthe Norvil fork,and to help deliverthatsharp, agile steering by cuttingdownongyroscopic weight. That ’s one reason whyfip -fopping it through the tightMallor ychicanebelied the factthatthis bike wasa750, especially
by the standards of amodernfour- cylinder Superbike –the Nor tonfelt morelike a600 Superspor tincomparison.
But the engine wasa diferentmatter. Strong,yes; fast,cer tainly ;rider-friendly, NOT!I’veridden several racing Nor tontwins over the years,including someprettyhot ones thatare competitiveinmodernday Classic racing,but Inever encounteredone that vibrated as badly as the Kuhn F750. Icould quiteunderstand whythe engine had been rubber-mountedbyJock Findlay’s team, presumably to make it at least halfway rideable,evenifsome of the powerthus got thrownawaydownthe frame
Therewasn’talot of poke below4000 revs,but then it came on song very strongly, pulling like atractor up to peak revs of 7200rpm.That’swhen Imanaged to persuade myselftohold the throttle open long enough forthe rev- counterneedle to get thathigh –beforeitbroke of altogether aftera dozen laps,presumably thanks to the vibes! But the immense vibration which set in just over 5000 revs discouraged revving it anyharder.Ifelt it ever ywhere: in my hands,inmyfeet,through the seatofmypants…I twas an all-per vasive
vibro-massage thatmade riding the bike at competitivespeeds very uncomfor table. Andyet atantalising glimpse of the promised land wasaforded by the waythe Nor tonpicked up its sk ir ts and fairly rocketed down the Mallor yPit StraightwhenIgot it wound up properly outofDevil’s Elbow Just that, with ever ything shak ing around, including my eyeballs,itk inda made it hard to know when to slowdownand brake for Gerards. It also made changing gear on the close -ratio 5-speed Quaifegearbox less easy to do smoothly,though Isuspect the reason thatthe toptwo changes especially were less than ideal wasbecause of the crossover link age ftted to deliver the one down, left foot shiftpattern that, being aYank,Mr. Johnson dictated.
Obviously something wasn’t quiteright, giventhatwechecked the carburation wasn’t toorich, and all quick Nor tontwincylinder racers then and nowhavesimilar rigidly-mountedengines like this one –and moretothe point, that’show Kuhn built them. From personal experiencewith my Matchless G50 motor,whenmyengine tuner experimentedwith diferent balance factors thatresulted in variousdegrees of vibration beforeheeventually hit on an ideal solution, Ididn’t think therewas much doubtthat waswherethe problem lay–the crank had been balanced incorrectly by the car engine specialists Mick Hemmings had resor tedto. As Ik nowfromriding otherTriumph and Nor tontwins thatMick’sbuilt the engines on, each to an improbable degree of nearsilkysmoothness by British parallel-twin standards,that’snot an issue thataficts his engines nowadays
Jim Boughen again: ‘Weused to lightenthe fywheels to quicken acceleration by using diferent centres, butitmeantwehad to use an unusual balancefactorfor Nor tontwins of 78% (the stock Commando’s was52%) and very special heavy metal insertstobalance the cranks,which we got from the Nuclear Research EstablishmentatHarlow.
‘Whatevervibration we ever got could alwaysbecured by rebalancing the crank, and the engines were so smooth thatDon Emde said it wasalmost like riding atwostroke when he racedone of our bikes We’d use 7200-7300rpm normally with no problems aboutthings falling of,and with the 4S cam there’squite abit morepower at the topend,soyou want to revthema bit.’
So there’sthe fx. Theresult would surely have been averyefectiveand enjoyablepackage, which otherwise summed up the benefts of 1970s-eraNortontwins in competition form, especially in shortcircuit use.Nocharge forthe developmentriding,Pete...
RC readers write, rant and rattleon...
Summattosay?Send your comments,hints,tips,tales of woeand derring- don’t to RCHQ@RealClassic.net
TR IXIE MIX
I’mrelatively new to the Yamaha TRX850 motorc ycle worldbut, like manyother TRXowners,I’m hooked and will keep mine for as long as possible.The Yamaha TRX850 has ahealthyfollowing around the worldwith an almost cult-like appeal.Currently,there is no UK TRXOwners Club per se,but one is fast approaching –look for‘ Yamaha TRXOwners GroupUK’ on Facebook
Originally built in 1995 as a spor ts bike mainly forthe Japan and east Asia market,the TRX waspromoted in Europe aftera decision wasmade by Lin Jar vis to ask Alan Cathcar ttoraceit.
LedbySatoKensie, the Over Racing team in Japan prepared the bike which wasnick named Trixie,and therest washistor y. Alan had agreat racing season in Europe and went on to win the Battle of the Twinsinthe USA on Trixie
Interest grew and Yamaha were cajoled and convinced into exporting the bikeinto Europe in 1996. However, due to overpricing, poorsales and the competition from other brands,the model ceased production in 2001.
Twenty years later, thereisahealthy following of the Yamaha TRX850, with its punchy10-valve, 850cc, dohc 270- degree parallel-twin engine.Somuchso, thatthe UK owners areholding a30th anniversar y eventatthe superbSammy Miller Museum in the New Forest on Saturday 21st June 2025. Alan Cathcar twill be the special guest, bringing Trixie with him.We’re hoping to
TIMI NG ISEVE RY TH ING
InoteinMembers’Enclosurethat some people have their vehicle’s MoT andannual ser viceatthe same time.I wasadvised by an employeeatVOSA, nowDVSA, to split them to six months apar tasthis means the vehicle is checked twiceasoften forthe same cost but alittle moreinconvenience. Not so impor tantwith aclassic that does under one hundred miles ayear.
Nick Crook,member
Mmm. Possibly not convenient if you havehalf adozen vehicles in one household which need MoTs and ser vicing each year.Wewould be visiting agarage /dealership ever ysingle month! Rowena
have the AirAmbulanceteamthere who will be selling someTRX T-shir ts,badges and other memorabilia, and there will be afew trophies to hand out.
So please come along and join us all at the SammyMiller Museum forthis memorable event.
JonathanLambley,member
FUEL FORTHOUGHT
Reading JacquelineBickerstaf ’s PUBTalk in RC251, whereshe recountedthe unpleasant side efects of siphoning petrol,brought back memories of an early eventin my motorcycling lifefromnearly70yearsago.I wasa 13-year-old schoolboy with aSaturday morning job at asmall printingfrm.One fellowemployeebecame agood friend. JohnnyWellmanwas aprinter,and he showedmeall thedodges to makelifeeasy Johnny’snormal meansoftranspor twas aBSA A7 500with aJet 80 sidecar attached, which he also used forrallies.One dayhe asked me to be his navigator. HiswifeSheila had playedthatrole, but they had recently
had ababyso she wasbusy at home.I enjoyed manyroadtrial competitions with Johnny, sat in the chair with awoodenboardclipped to the handrail, and an OrdnanceSur vey1”map fxed to the board. But one trial stands out in my memor y.
It wasa nightevent thatstarted somewherenearBath. It wasaround midnightand we were travelling on the A46 Bath/Stroud Road,close to the Cross Hands Hotel nearOld Sodbur y, when we ranout of petrol. Iimagine Johnnymusthaveforgotten to topupthe petrol tank.Anyway, therewere no petrolstations nearby open at thattimeof night, so Johnnydecided we shouldtry and get the outfttoChipping Sodbury –some three miles away –wherethe PoliceStation wasmanned24hours aday.Hethoughtthey mightbeable to help us
If youlook on amap,Old Sodbury is in the Cotswolds and Chipping Sodbury is below the Cotswold escarpment, so it looks like it should be along downhill run. In fact, the road is quitesteep downhill in places,but level forquite abit of the way, with the odd bit of uphilltocontend with.
Aftera lot of sweatand efor twe eventuallyreached the PoliceStation in
YUASA’SANSWE RS
Afterthe recent correspondence about modernbatteries,Iasked Yuasa’s technical help deskabout whether AGM-gelbatteries aresuitable forold motorc ycles like my Moto Guzzi over longdistances. They replied:
‘Generally speak ing,the AGMmotorcycle battery will be superior to theconventional wetfooded batter y. Smar tchargers will adjust the current output depending onthe batter yresponse to charge to reducethe possibilityofover- charging the batter y.
‘Infrequentjourneyswill notnecessarily shor tenthe batter ylife, alot willdepend on your batter ymaintenance. Abattery thatis marked as “maintenancefree” only means thatyou do not need to monitor electrolyte levels or topthem up.All leadacid batteries (including AGM/GEL)need to be kept in high statesofcharge,especially during thewinter monthsorwhen not usedfor longperiods.
‘I tisalsonot necessary to keep them on
long periods of foatcharge.Motorcycle batteries arenot designed forthis.Doing this keeps the acid strength high, which over time can cause internal corrosion issues.I tisbetter to fully charge and then allowthe batter yto discharge,then topupwith supplementar y charges as necessar y.
‘Floatcharge is when alow constantvoltage is applied to abattery to keep the voltagelevel up while the batteryisinuse (for example abattery in afre alarm) .Similar to trickle charging,where alow current is applied to keep the batteryin high statesofcharge.(when batteryisnot in use). In both cases the acid strength is highand can cause issues over time.
‘I tis better to allowthe batter ytodischarge and then recharge.Inthe case of the wet batteries this also helps mixthe electrolyte to preventacid separation, not so muchas issue with AGMbut still useful as it also helps preventthe liquid elementofthe electrolyte
the early hours of the morning.The police stationwas,and still is,locatedrightinthe middle of the mainstreet.After Johnny explained ourplighttoaconstable on the frontdesk,asuperintendentcame out to help.His car wasparked outside,and he wasmorethan happytohelpus. He found agallon can and arubbertubefrom somewheretosiphon petrol from his tank and transfer it to the BSA.
Having inser tedthe rubberpipe in the car ’s tank,hegaveamighty suck,and wasrewarded with amouth full of petrol Youhavenever heardsuchshock ing language from apoliceman –yet alone a superintendent! Happydays.
Alan Freke, member
Brilliant stor y, Alan. Adisreputable friend of mine long,long ago always carried asiphon tube in his sidecar.Hehad arubber bulb attached to it,sonever needed to actually swallowpetrol.Cars in the those days rarely had locking filler caps FrankW
being lost.Overtime youwill noticethe time between charges reducing as the batter y ages.This canhelp identify apotential failure beforeitactually happens.’
Roger Rowland,member
Brilliant stuff! Actual facts! Thanks,Roger. FrankW
SMOOTH START1
Isympathise with PUB.I toohavebeen grappling with a‘notstarting when hot’issue on a2-stroke –not an Enfeld but aBantam. This is a1970 B175, the last of the breed,that my partner acquired ayear back onpicking up bikes again aftera40year layof.
Cold star ting is fne as long as aprocedure is followed–food,k ick-to-prime then ignition on –but she could not get it going when hot, whateverchoke /throttle setting wasused.New crankoil sealshavebeen ftted,eliminating thatworry.I have fddled endlesslywithignition settings,battery charge and of course carbsettings including jets with no avail.Icould star titmyselfafter afew big lunges,after which it ranfne,but with her shor terstatureshe could not and she becamerather demotivated.
Anew Amal had been ftted by the restorer,which made me questionwhether it wasthe wrongboresize. Burlen’s website advises a626/300for the bike (whichthis bike has), with the note‘Although this is a 2-stroke application the carburettor spec calls for4-stroke components.’ Icalled Burlen to check this and wasadvised that for2-strokes the carbalsoneeds an angled mixer tube exit (the end stick ingupintothe
airstream), which this bike also has
TheBurlen chap thought to ask if my carbwas ftted with the fxed pilot jet buried at the end of the air screw tunnel,inwhich case no screw-in pilot jet should be ftted.Morethan achink of lighthere, as my carbdid indeed have the fxed jet, plus ascrew-in one.I tturns out thatdoubling up the pilot jet prettywell guarantees star ting problems.Nowonder the air screw needed to be screwed in almost tight.
Simplyremoving the screw-in jet has transformed the bike. It ’s ahappyfacenow when I suggest aride out.
NotetoBurlen: mightbe worthadding these twobitsof advicetoyour website.
HugoRose,member
Brilliant info,Hugo, thanks so much for
SMOOTH START2
Istripped the fywheel ignition system of my recent buy,a 1961FrancisBarnett Cruiser which uses the Villiers 250 2T twin engine.Iboughtan electronic ignition system from SteveatVilliers Services.This complete electronic ignition system replaces ever yoriginal ignition par t. Ifeel thatIwill need this new system to get me easy star ting when the engine is warm
David Pattison, member
That ’s really useful,thanks Letusknowhow well it works? Knowledge is power, so they say FrankW
sharing.I completely sympathise with your par tner:several of our old bikes have been just abit tootall or toobroad for me to star t comfor tably and thereforeuse confidently.I must admit,the current FakebirdScrambler really is tootall for me! Rowena
WINTERWARMERS
Not ever yone rides through winter, butI tr yto as long as the roads arenot ic y. Thereare some really niceriding days to be had through winter when the temperaturedrops and the sun is out but when the air temp is still very chilly.Like alot of riders, Isufer from cold feet and cold hands.Ihavehad bikes with heatedgrips,but I fnd they do not always keep my hands warm in the correctplaces.Also,6Velectrics and old bike wiring don’t alwaysagree with the increased electrical loads!
Keeping my feet warm is another challenge; at least it was, until Idiscovered heatper formance.co.uk This companyis based in the Netherlands and supply heated socks,glovesand other items of clothing,all to a very good quality.
Iboughtsome heatedsocks,primarily for skiing,but found they work admirably on the motorbike and when working in acoldworkshop So Iboughtsomeheatedgloveswhich work from thesamesizebattery and connectors.This means that Ican have warm feet and hands,whichever bike Iride.The ion lithium 7.4V batterypacks ft into pockets on the glovesand socksand are connectedvia ajack plug and lead
Theglovesare pre-shaped foreasy grip of controls and the socks arever ywarm, even when turned of!The socks canberemote controlled via Bluetooth, although Ihave onlyused this acoupleoftimes in the three years Ihavebeen using them.The socks can
be washed by hand oncethe jack plugs have been protected by rubber sockets (which areprovided along with the charging unit). Both socks and gloves have three heat settings.‘Low’ givesa nicecomfor tabletemperaturewhich lasts forbetween 8and 10 hours on afully charged batter y. Mediumisdefnitely toasty and High can be uncomfortably hot When not being used,the batteries should be kept at around 50% charge to extend their life, and can have alifeof1000 charge cycles.Fullcharging takes about four hours
StuThomson, member
Itook alook at their site–thanks for the suggestion, Stu–and wasver yimpressed by their motorcycling range.The heated /thermal under wear,jacketsand so on could be really useful for pillion passengers.I tend to find that Istay warm enough, doing all that complicated riding business at thesharp end,but well rememberthe miser yoffeeling frozen on the back… Rowena
HERALDIC DEVICE
Ihad not anticipatedthatOllie’s article on his son and his Herald could be so good thatitseemed to be rising of thepage! It was able,for me,tohit so manymarks,someofthem nostalgic and some vis àvis thepresent-daymotorcycling scene Good oldOllie andson. Here’stocheap bikes,the sor twhich arethe best fun and the most involving,bringing us together.
Nigel Stennett-Cox, member
LIFT OFF!
John Jordan mentions in RC250 about his Honda CB400Aand thedifculty he has gettingitontothe main stand. He’s not theonlyone withthisissue.As we age,westruggle with theweightof the bike.O ften, the designofthe main stand itself is lessthan ideal.Gone arethe days of the centrestandwhich allowedthe bike to balancenicelyon either wheel –aswith older BMWs, whichcan usuallybeput on thestand with little efor t.
Thereis, however, asimpleand cheap solution to this problem when you’re at home in the garage.This makes maintenancetasks such as chain tensioning and lubrication,oil changes,etc,much easier. Youjust need asmallramp with a metalend stop.Mygood mate Tony made one and had enough materials leftto make another forme.
dropping of the other end of the ramp Oncethe bike is on the stand,it’ssimple to just wiggle the stand outfromunder the wheel.Isentafriend of minethe dimensions and he made one foruse on his PanEuropean 1300. He is nowable to put thatonits main stand at home. Iembellished mine with somenon-slip matting
At the time Ihad aHonda Crossrunner, abrilliantbut heavy bike thatwas next to impossible formetoput on its main stand. Thestand pivot waswell to therear of the (heavy) bike; it had to be because of exhausts under the crankcase.With the little ramp it waseasy and I’ve used it ever since.
We all know that putting abike onto its main stand is much easier when thebike is pointing uphill.But…whileit’seasier to put onto amain stand on an upward slope,getting it of again can be difcult. Theramp,madefromacouple ofbits of chipboard, has achamferedend up which the frontwheel of the bike is pushed.This goes onto alevel par tofthe stand thatis about twoinches above groundlevel.The metal stop at the endpreventsthe wheel
NOTSOSHAKY
I’mmost interested in the excellent Laverda stor ybyStu Thomson. Theonly issue Ihaveis Stu’scontention thatthe 750twins vibrated badly. Icovered thousandsofmost enjoyable miles on these twins,and have foundthat the 750 twins aremyfavourite.Their most endearing traits arethe most robust nature, excellenthandling, superbbrakes and lack of vibration.
Ever yt ime we had one in the wo rk shop tha td id vibr ate, in most cases it wa sc au sed by the bolt tha ts ecures the thirds ilencer belowt he en gi ne being lose or mi ssi ng
On the ear lier models, sans the third silencer,t he causes wo uld be in suf fic ien tly to rq ued engine bol ts,h ead stock playa nd
Theother tip Ihaveisfor check ing the oil level in bikes thatonly have asidestand and need the oil to be checked when warm. Ifound thattrying to hold abike vertically while either dipping the oillevel or peering into asightglass is fraughtwith danger.I needed asimple and quick wayofholding the bike vertical while check ing the oil level
On thatauction websiteIcameacross Chinese frontwheel chocks thatare adjustable in three positions,according to the sizeofthe wheel.Iuse mine on my CL500 (19”) and my CBR650R (17”), quick ly swapping fromone to the other as the pin thatlocatesthe clamppivot pointis retained only by Rclips.Wheeling the bike into one of these holds the bike safely enough, butplacing asuitable sizepieceof wood under the sidestand allows the bike
fau lt ys ilencer moun ting rubber s.
Vibrating machines would not last in 24 hour races. Laverdatwins dominatedlong distance racing of the era. Ilook forwardto‘Part TheLast ’of Stu’sadventures
Roger Slater,member
to be held in aver tical position. Ioften do other maintenancewith the bike suppor ted in this waywhen the wheels can be on the ground,other wise Iuse an Abba Superbike stand
Ihope these suggestions maybeuseful to other RC readers
Alan Taylor,member
Really helpful,thanks Alan. Imust admitI shudder and tr ytobebusy doing something else at the other end of thegarden when Frank suggestsheaving his great heav y modern Triumph triple ontothe paddock stand! Rowena
Indeed; I’ve only ridden acouple but wasstruck by howsmooth the motors were –especially compared to the British equivalent engines! But still,it’sagreat
excuse to use an old photoofthe inimitable Dave Minton, hooning around on aLaverda back in 1978… Rowena