Per­haps the pret­ti­est of all the later 2-T twins. And this one re­ally is pretty

Some peo­ple yearn for one par­tic­u­lar bike for most of their adult lives. Ja­son Staunton from Ire­land, now of Liver­pool, is one of them

Practical Sportsbikes (UK) - - Inside - WORDS PHIL WEST PHO­TOG­RA­PHY STU­ART COLLINS

MY FIRST BIKE was a Suzuki RG80, when I was 16-17 in the West of Ire­land, and a guy I knew had one of these,” the now 34-year-old Ja­son tells PS, ges­tur­ing to the glo­ri­ous, re­cently-re­storedyam tak­ing pride of place in his garage along­side a DR-Z400 SM ‘daily driver’ and his mis­sus’s GN125. “I just fell in love with it and said one day I’d want to re­store one.” The ma­chine he’s re­fer­ring to with such af­fec­tion is, of course, yamaha’s ex­quis­ite but short-lived TZR250R ‘3MA’. Bet­ter known as the ‘re­verse-cylin­der’, the two-stroke, twin pot GP replica that was, in 1989, the suc­ces­sor to the orig­i­nal, more con­ven­tional 2MA (1KT in Ja­pan) and which in turn was suc­ceeded by the V-twin 3XV in 1992 be­foreyamaha ceasedtzr250 pro­duc­tion in 1996.

But while that first 2MA be­came a com­mon sight in the UK both on road and track, the 3MA and 3XV were Ja­pan-only jew­els that only ever vis­ited Blighty as grey im­ports.that, and the fact that each is an ex­quis­ite, road-go­ing dop­pel­gänger, from en­gine con­fig­u­ra­tion to styling, ofyamaha’s GP 250s of the day, makes them now about as de­sir­able 250 GP repli­cas get – right up with the very best Honda NSRS.

For Ja­son, how­ever, the 3MA, ever since those im­pres­sion­able days in­west Ire­land, was ‘the one’. “It’s just kind of the unique­ness of it,” he says to­day. “The carbs out the front, the cans out the rear...”

Want­ing specif­i­cally a project to re­build rather than a fin­ished bike, Ja­son’s search took quite a while. “Even­tu­ally I came across

one on ebay about two years ago, bought it blind from some­where in Kent, and had it de­liv­ered up here.”

If he’d in­spected it in per­son he might have re­alised it was a bit of a mess. “It had been off the road since 1993, the tank was blue, the pow­er­valves were held to­gether with nails and it didn’t have brakes,” Ja­son re­mem­bers. On the plus side, though, it was largely com­plete and he paid just £1300.

“The guy had had it since ’93 and had been slowly ob­tain­ing the bits and loosely as­sem­bling it – he more or less had 95 per cent of it.”

Bet­ter still – it worked, although it also im­me­di­ately showed signs of a fault that would taint the whole re­build.

“When I first got it back I at­tempted to start it, which it did,” says Ja­son. “It ran,

and pissed oil out of ev­ery pow­er­valve ori­fice. It ticked over OK – but it was re­ally hes­i­tant to rev.you had to slowly roll the throt­tle be­fore it would clear and rev freely above 4000rpm. I ran it for a few min­utes then started dis­as­sem­bling it.”

Af­ter strip­ping, box­ing, bag­ging, mea­sur­ing and in­spect­ing pretty much every­thing, Ja­son or­dered re­place­ment bear­ings be­fore turn­ing to clean­ing and re­fin­ish­ing the chas­sis.

“To be hon­est I’m not very pleased with my choice of pow­der­coater. It’s OK from a dis­tance but not so good close up. He also man­aged to lose half my rear caliper!”af­ter that Ja­son went totriple-s (“Who do some very good work”) be­fore he started re­assem­bling with new bear­ings and so on.

Then he started on that fa­mous re­ver­se­cylin­der twin.

“By that point I hadn’t touched the en­gine yet. It still had 27 years of cor­ro­sion. So I stripped that and did the same.”

Crank runout mea­sured true so Ja­son changed only the outer bear­ings and not the cen­tre.while apart he had the cases aquablasted then he turned to the top end.

“There was some dam­age on the Nikasil lin­ers and a nick in one ex­haust port,” says Ja­son. “And as I men­tioned, one of the pow­er­valves was held to­gether with a piece of nail so I needed some pow­er­valve com­po­nents, too. But I man­aged to source a set of bar­rels with com­plete pow­er­valves on thetzr fo­rum and had them shipped off to thetun­ing­works in Sleaford.”

The bar­rels were cleaned and re-nikasiled and the top end was re­assem­bled.then the TZR’S fu­elling is­sue resur­faced.

“I had the carbs aquablasted and re­placed all the jets and nee­dles and then, two or three months ago, the day came to start it,” Ja­son says. “I was quite sur­prised – it fired up rel­a­tively eas­ily.”

But all was not well. “It seemed to be func­tion­ing right, tick­ing over smoothly and not now piss­ing oil out of ev­ery ori­fice – but it was still not tak­ing throt­tle,” says Ja­son. “You still had to roll the throt­tle re­ally slowly and let it build.then it’d start clear­ing it­self and rev.”

And no mat­ter what he tried, he couldn’t get to the root of the prob­lem.

“The carbs have been on and off about 20 times in the last cou­ple of months try­ing to fig­ure it out,” he says, re­call­ing the frus­tra­tion. “Ev­ery sin­gle com­po­nent taken out was ei­ther re­placed with new or aqua blasted or ul­tra­son­i­cally cleaned. I was try­ing dif­fer­ent nee­dles, dif­fer­ent nee­dle heights…”

Fi­nally Ja­son re­al­ized that a tiny, pressed-in, brass noz­zle jet was miss­ing on both carbs.

“What hap­pens is that some­times, when you re­move the emul­sion tube, they can fall out.they’re very, very small and easy to miss.”

They’re also hard to come by. “I had to go to Fowlers and get them or­dered from Ja­pan,” Ja­son says. “For 70 quid! But they went in and then it ran much, much bet­ter. It’s still not the sharpest on the throt­tle but

I’ve been told that in re­al­ity that’s as good as I’m go­ing to get.”

But even with the en­gine now sorted, Ja­son’s prob­lems weren’t over.

“When I orig­i­nally started to dis­as­sem­ble it I’d no­ticed some of the frame lugs the en­gine mounts on had been cut, ro­tated 180 de­grees and rewelded,” Ja­son says. “The only ex­pla­na­tion was that the pre­vi­ous owner thought the frame had been used in Su­per Sin­gles rac­ing with some kind of four-stroke sin­gle in it. I’ve since found ref­er­ences to the 3MA frame be­ing used in sin­gles rac­ers so it ties in with what he was say­ing…”

The only rem­edy was to have the lugs cut, ro­tated back and rewelded while the side­stand – or rather, the lack of one (an­other in­di­ca­tor of a rac­ing past) – re­quired sim­i­lar re­me­dial ac­tion.

“A lo­cal ma­chine shop welded a piece on for me and I just filed it down and tried to get it back to how it orig­i­nally looked,” says Ja­son ca­su­ally. thank­fully, most of the rest was more straight­for­ward.

Forks were dis­as­sem­bled, aqua-blasted and re­built, still with the orig­i­nal springs.the rear shock, too, was stripped, cleaned and re­fin­ished. wheels were stripped, blasted, coated and had new bear­ings and seals.

The discs are the orig­i­nals while the calipers have been re­built, painted and given braided lines. “And I must say I’m quite im­pressed with how good the front brakes are,” Ja­son adds.

Switchgear and clocks were sim­ply cleaned while most of the wiring was good, too.

And the re­sult, fol­low­ing the re­paint­ing of the blue tank back to orig­i­nal white/red by Fast Line in Pre­ston plus the ad­di­tion of some tem­po­rary Chi­nese-made replica body­work, is as you see be­fore you now.

“There’s still some things I need to change, like some of the fas­ten­ers, maybe re­build the shock and the Chi­nese body­work… but that’s just a stop-gap,” Ja­son says.

For the time be­ing the orig­i­nal fair­ings are in the at­tic await­ing a re­paint. “Orig­i­nally I got some re­ally, re­ally ex­pen­sive quotes to do the whole body­work which drove me down the route of get­ting this Chi­nese stuff,” Ja­son says. “They’re only £300 or so and they’re OK for now. Plus I needed the belly pan ‘V’ piece which was miss­ing. I’d also like to do a cou­ple of track days on it. It’s so small and light they’re bril­liant fun on track – so that’s an­other rea­son for the Chi­nese body­work. Even­tu­ally, though, I do want to put the OE stuff back on and get them painted the same as the tank.” And what about af­ter that? “I’m get­ting pretty des­per­ate to start on some­thing else,” he ad­mits. “Although I’m not sure what.”then he casts a mis­chievous glance at his DR-Z. “Maybe a su­per­moto with a 500 sin­gle-cylin­der two-stroke in it,” he adds. “And of course it’s got to be a two-stroke, every­one knows they’re a lot more fun.”

A fit two-stroke is worth any amount of resto pain

“And this is an­other one of me swim­ming with dol­phins”

One of the best rears around

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