When it comes to two stroke tuning there is only one name - Fast Bikes

tuning godHalf dictator, half mass-murderer,Stan Stephens has ruled the twostroketuning roost for decadesDon’t take the picture from thatangle, I look like a crossbetween Harold Shipmanand Saddam Hussein.” I’ve knownStan for a number of years andalthough photographer Phil looked abit shocked by this comment it’s all parfor the course when you’re in thecompany of the UK’s, if not theworld’s, best two stroke tuner. Stan isdirect, outspoken and genuinelyentertaining to be around.Having been involved in the tuninggame for over 40 years, there is little thatStan hasn’t seen, few he hasn’t argued with,and even less who he hasn’t tuned a motor for.In the late 1970s and 1980s two strokes werethe bikes to race, and his name was on the sideof the vast majority of the bikes winning cluband British races. His is a reputation that haswithstood the test of time and now, eventhough two strokes are becoming less and lesscommon, it is still Stan that enthusiasts, racersand collectors are turning to when it comes togetting their smokers sorted. But it all had tostart somewhere and as with most things inStan’s life it started with sheer bravado.“I went to college after school but then Ijoined a motorbike shop when I waseighteen, a place called Tun Motorcycles inTunbridge Wells. I didn’t do anapprenticeship because Ilied to them and told •When it comes to two stroke tuning there isonly one name – Stan Stephens. A man withfully synthetic oil running through his veins…Words: Jon Urry Pics: Steinhardtmrtwo-stroke88 august 2010 fast bikes mag.comfast bikes mag.com august 2010 89

tuning godStan StephensGet the tune wrongand you’ll find yoursmoker doing thisYou only getout what youput in...The RD500…“When the RD500 was launched in theUK it was on a stage with spotlights allover it. Anyway one of our lads climbedon the plinth and stuck one of our StanStephens stickers right under the V4logo. The bike was red and white and sowas our logo, it matched perfectly. Noone from Yamaha noticed and it stayedthere all show and even appeared in allthe Yamaha publicity photos in all themagazines. Fantastic…”I oweall mysuccessto theracers Isponsoredand It wasthroughthemwinningthat ourbusinesswas builtThe animal…“I’m working on a 611cc two stroke twinusing 350LC cases. A standard YPVS is a64mm bore with 54mm stroke, I’vetaken it to a 78mm bore with a 64mmstroke, I reckon it should be good for150bhp so I’m going to stick it in mysidecar. I could do it for a road bike if youwant, it would easily fit in a 350...”Two wheels good, three wheels better.Four strokes? Forget ’em• per cent of the bikes out there were tunedby us at the time. At the first we were the onlyones tuning but soon anyone with a filejumped on the bandwagon, but ours were thebest. We were never the cheapest, I actuallyused to make sure we were the mostexpensive, but we did all the development,others copied our work.”Imitation, they say, is the sincerest form offlattery and once you put your engine out onthe race scene it’s there for all to inspect.“I spent weeks testing two stroke motorson dynos before anyone else really thoughtabout doing it, getting everything spot on. I didtwo weeks solid once testing reed valves.Different thicknesses, tapers, using backingplates, you name it, but our bikes were quickand it got us the work.”This is Stan’s blank canvas;a motor out of the frameand ready to be tunedthe more hours you put intodevelopment, the more you learn ”As with anything there isn’t really anymagic to Stan’s tuning, it’s down todedication, hard work and a lot of practice,patience and experimentation. Trial and error,all driven by the fanatical need to win.How do you find out what the minimumsquish you can run on a head is? You keepskimming it until the piston starts to hit it.How do you find the optimum combustionpoint? You keep playing with the ignition untilthe detonation is perfect. The more hours youput into development, the more you learn.Stan’s team put countless hours in and madesure everyone knew that it was their bikesdoing the winning.“I always made sure our bikes looked good,in our red and white colours and with our logoon them,” remembers Stan. “I was looking atthe records a few weeks back, I’ve sponsoredover 160 different riders over the years,something I’m very proud of. I’m a racingenthusiast, I’ve always wanted to be a racer, ora race team manager or race mechanic.”Stan does give the impression of being afrustrated racer and at the track he treatedevery race his engines were in as a battle.The RG500“Again, up at the show Suzuki launchedthe RG500. One of our lads walked overand looked at the bike, asking all thesequestions in a loud voice ‘how many yougot coming in, when is the on sale date.’He had already sussed the bike, helooked inside the fairing and sureenough it had 398cc on the barrels, itwas the Japanese 400 version, Suzukihadn’t even made the 500 yet, theywere livid!”“Everything I’ve ever done I’ve done as awar. I don’t now, but in the 1970s and 80s Ihad tunnel vision. My big competition wasTerry Beckett, it was like North/South tribalwarfare. The paddock was unbelievable, therivalry between racers was so intense, but thefunny thing was me and Terry used to watchthe races together! But I always wanted to beathim. I treated tuning as racing. Watching myriders was just as exciting, I’d get indigestionfrom the adrenalin. But it was getting silly, therivalry between us was so strong that we werelosing money, blowing cash on engines just tobeat each other. Eventually we spoke andcame up with a pact, we said to each other‘let’s just stick to what we know and try andmake some money!’ The tuning I do now onLCs is exactly the same as in the 1980s, thedevelopment kind of stopped at the point.”But times change and although Stan isknown as a two stroke tuner his firm hasdabbled in four stroke tuning.“Two strokes were becoming less and lesspopular by the 1990s so I needed to develop areputation for four stroke tuning. I employedone of the best four stroke tuners around•92 august 2010 fast bikes mag.comfast bikes mag.com august 2010 93

tuning godStan StephensEveryrace wasan advert,I was on it24/7The RD350 YPVS“We always had a really closerelationship with Yamaha and the presshad some spy shots of the 350 PowerValve before it was launched. Anyway, Igot a 350LC top case, sprayed it blackand stuck it on a couple of YZ125 barrelsthat had YPVS on them, just like the spyshot. I stuck it on my stand at the showwith a sign saying ‘latest 350 PowerValve development under way, availablefor this season.’ Yamaha came over andsaid ‘Stan, you know and we know youhaven’t got a YPVS, I won’t say anythingbut I’ve got dealers going mad, howhave you done that…’ Everyone came tome when the 350 YPVS came out to gettheirs tuned because they thought I hadbeen working on them for ages…”• and looked at the classes we could race in.We needed to wave the flag at the highest levelwe could afford, so we built a supermonoracer, which was then the big up and comingclass. We won the TT with Jim Moodie andfrom that people just assumed we could tunefour strokes, which we could.”But Stan has no love for these kind ofengines, certainly not the passion he has fortwo strokes. “You have to know what you aredoing with a two stroke, you don’t with a fourstroke. With a two stroke you are doing ityourself, with a four stroke you buy thepistons, buy the cam shafts and just take itapart and put it back together. There is lessskill, it’s just fitting. At the top level it’sdifferent, but at club and national there is littleskill, you have to be a good mechanic butthat’s it. The tuner develops the cam shaftsand the like, not the guy bolting them in, mostaren’t tuners, they just assemble engines.”Reputation is something Stan holds veryprecious and it is something he fiercelydefends. Stories of Stan confronting peoplewho he feels have bad mouthed him to thepaddock were common in the 1980s and eventhough he has mellowed a bit today he still94 august 2010 fast bikes mag.combelieves in a strong reputation. “Every racewas an advert and I was on it 24/7. I’d chaseup every bad comment and find out why itwas said. The reason I’m still here, and I’mvery proud of this, is that I’ve never let anyonedown or ripped anyone off. If there is an oilseal on the invoice, it is in the engine, I’venever, ever, done anything dodgy and I neverwould. I’ve never lied and that’s why I havemy reputation. It’s taken a long time to build itup but people realise they can trust me, that’swhat I’m more proud of more than anything.”But the two-stroke tuning industry haschanged, Stan closed his tuning centre in theearly 2000s to work from home as he nearsretirement age. Racing has now taken a backseat and Stan has turned his attention toclassic two stroke enthusiasts, a considerablyeasier group to work with.“Books and the internet can only tell you somuch, you have to know what you are doinggiven set parameters, stock carbs and stockcans and this is what I have inside my headand why people still come to me. It’sexperience and I’m now doing more roadbikes than racers, mainly restorations. Thebest thing is there is no rush, they give me anContact StanStan can be contacted viawww.stanstephens.com If you want totalk two stroke engine problems there isa £1.50 a minute Two Stroke helplinenumber which he will chat to you all daylong on as well as contact details shouldyou need an engine sorting.engine and tell me to call them when it’s done,racers used to stand there looking at theirwatches. Everyday I get a call saying ‘you usedto tune my engines in the 1980s, can you doexactly the same again.’”How much longer can the mostknowledgeable two-stroke tuner go on? It’s aquestion that is worrying some customers.“I had a chap call me and I tuned a set ofRD barrels for him. He calls up a few weekslater and asks if I can do another set. I askedhim if he had damaged his, in which case Iwould redo them, but he said it was a new setof barrels. I asked why and eventually he said‘well Stan, I don’t know how much longer youwill be around…’ I’m not gone yet!” •