Yamaha YPVS Special

Yamaha YPVS Special

Yamaha YPVS specialThe “Valve of Joy”

Those of you who regularly attend the many shows up and down the UK will have no doubt have caught sight of this fine looking machine at some point in time. Owned and lovingly built by Andy Holmes, more commonly known throughout the RD world as “Trig”, this distinctive looking Yamaha is the result of around three years tinkering to achieve his desires.

Trig is little more used to four wheels as in the past he has been a regular competitor on the UK Kart racing scene using a number of bike engined karts, stringing together an impressive tally of trophies and championship placings in the eleven years that he took part. A nasty crash while competing in the 2000 UK championships saw him retire from the sport enabling him to concentrate fully upon his newfound, two wheeled, passion.

The RD began with a standard LCII, complete with the all important matching engine and chassis numbers, which Trig then chose to “improve” in selected areas, the results of those modifications really are as good as it gets in the world of RD specials. He has created a superbly turned out, respectfully and tastefully modified special as first-rate in every aspect as the original machine. Heads can be seen turning whenever folk pass the “Valve of Joy”, not that many do actually walk on by without stopping to admire for a little while as, what looks at first sight like a clean std Yamaha is, the more one stares at it, a finely crafted and radically improved special.

Yamaha YPVSAll this effort and yet the machine has been completed without the great expense usually reported, or the turmoil and heartache for that matter, as each and every stage has been guided and carried out by Trig himself along with few selected friends.

The cracking paint work for instance, silky smooth and very professionally applied, was actually completed in exchange for a set of F2 power jet carbs. Whilst we are on the subject of the paint, yes we all agree, if it is green then it ought to be a Kwak, but lets face it, the scheme does rather work. A “green meanie” was actually not the inspiration, the shade is Roulette Green and, along with the superbly complimentary silver frame, is a colour scheme more normally associated with the Hinckley made Triumph Speed Triple.

Set off completely by the many polished ally bits and endless amounts of dome headed stainless steel bolts, albeit it tastefully done, the unmistakable shape of the power valve, more usually spied in black or white, actually works well in this “traitors” colour scheme. Of course it helps that the original lay out of graphics and style have been retained firmly asserting the fact that the Yam design team got it pretty much right back in 1983 when the YPVS first hit the scene

YPVS specialEngine wise, this particular Power Valve is virtually standard except for a welded crank centre, for extra stability, and the usual reed valve spacers giving a smidgeon more mid range smoothness. This bucks, quite considerably, the current trend of tuning, porting and other such techniques in constant search of the unattainable, also, where many have gone down the K&N air filter route, the original air box still remains.

In keeping with the whole “Valve of Joy” concept, a pair of uniquely made pipes, hand crafted by Tee Emm racings, Andy Bown, yet another member of the small, but mechanically capable, Trig appreciation society, add considerably to the few performance enhancements found on the bike. Soon these mild steel pipes will be replaced by a pair of stainless items from the same fabricator hopefully adding further still to the power delivery and business like look already exuded in bucket loads by the bike.

The retro style TZ wire wheels, fantastic looking and like every piece of alloy on the bike, very well polished, are not just aesthetic as they do greatly aid turn in and general manoeuvrability. For the front, a pair of simple but very well turned out spacers either side sorted the job out while the rear gave some much more serious head aches which once again have been over come by Trig and his Coalville engineering mafia!!

Yamaha YPVS 350 specialAiding the light weight wire wheels when trying to manipulate the bike around the twists and turns is the extra bit of width provided by the off road type handle bars, coupled with a pair of top yolk mounted risers. These also keep the rider well upright, reducing much weight off the front tyre during acceleration, and results in unintended wheelie displays all over the place in second and third, anyway that’s my case for the defence your worship.

Modifications still left to be completed are the rebuilding of the spoke wheels as they are from a very early model TZ and the rims are too narrow for the correct fit tyres to be implemented, the rear rim would be more suited to the front fitment tyre while a wider WM 2.5 item needs to be sought to keep the 120/80 section rubber in check. Even though the profile isn’t yet quite right, the Bridgestone BT45 tyres still hold everything in firm order even when hustling around the Donington Park circuit.

Other aspects of the running gear have been more radically improved with twin CBR 600 brake calipers which grab, via the standard Yamaha master cylinder and stainless steel hoses, a pair of dinner plate size, FZR1000 disc rotors. These give a harsh, almost brutal impact upon the little bikes trajectory should the lever be pulled too hard and the forks feel as if they may well yield under the strain of modern day anchoring when fully applied. The set up is perfectly controllable however and one finger braking is all you may ever need in normal use. Certainly buzzing around the Donington track produced nothing but great stopping power allied to superb feel and predictable handling.

350 YPVS specialThe up rating of the braking with modern items doesn’t look at all out of place on this twenty year old giant killer although, like the fitting of the wheels, much machining work has been carried out to get this professional looking result. Trig would love to claim the credit for this superb level of workmanship, and nearly did the crafty geezer, but when pushed admitted to it being the result of yet another handy to have mate, Jay, who spent many an hour setting up large chunks of raw aluminium billet turning them into the beautifully machined pieces you see here.

Once the discs had been spaced out sufficiently away from each side of the wheel hub to give the calipers adequate clearance from the spokes, it was then a relatively simple task to fabricate a pair of calliper mounting plates. This time Trig really did get stuck in himself, he had probably run out of favours or such like to trade in, carefully cutting out the intricately shaped aluminium plates required to mate the Honda stoppers with the vintage Yamaha fork legs. With the wheels being from a pukka race bike there is no facility to drive a speedo, for a while Trig used the bike without one, but a remedy was soon to hand. A simple scooter type speedo drive was found with the same gear ratio as the Yamaha item and this has bolted almost straight on, taking its drive from a simple slot formed into the front hub.

Yamaha YPVSOn the top of the fork sliders is bolted the all-important, well they were back in the 80’s, Micron fork brace. It is difficult to say exactly what impact these things actually have upon the stability of the front end as a well set up “Power Valve” always was a pretty good handling bike, and the TZ racers they were based upon never had them, but they do look good and don’t appear to have any adverse effects so what the hell.

The rear brake disc had to be spaced out to line up with both the TZ hub and the swing arm mounted calliper bracket. A large aluminium hub was once more machined out of billet, again courtesy of Jay and his CNC machinery, to bridge the gap and a disc taken from a Fazer 600 was then bolted directly to this. A small single piston, fully floating Brembo calliper, borrowed from a KTM typically has little or no effect upon halting the proceedings and can be literally stood on before anything appears to be happening at speed. It is rather handy for wheelies though as, so I’m reliably informed, just enough pressure is available to keep the wheel aloft while holding the throttle pinned firmly against its stop.

All of this jiggery pokery at the back end is neatly bolted onto the obligatory polished aluminium, box section Metmachex swing arm. This huge chunk of metal disappears completely into the silver frame and polished alloy almost without trace rather than standing out like a facial impediment for all to see. The swing arm not only looks good, it is significantly stronger that the standard yam item and also makes chain adjustment a whole lot easier thanks to its eccentric cam, although ride height is also altered with excessive movement of the inserts. As it is currently set up the wheelbase and steering head angle, trail etc appear to be virtually unaltered and in use the “Valve of Joy” is a sprightly performer just like the original machine was and still is.

Yamaha YPVS TestThe engine is strong, only so much more so than the original set up, thanks to those big section pipes, and eager to be let off the leash for a gallop around. The power delivery is sharp and exciting, mainly due to the lack of a cush drive in the race wheel, and yet progressive and easy to keep in check, especially on a track such as this, a tight twisty B road would no doubt produce an even greater sense of exhilaration and speed. With a top end realistically around the 120mph mark and acceleration to match most machines up to this point, a well set up YPVS could be all one could ever need to get the right kicks.

Although Trig is yet to get the “Valve of Joy” onto a dyno to establish the actual impact that the exhausts have, it does feel far stronger in the mid range with quite a boost at 8500rpm where maximum torque is produced. The fatter pipes do make the engine quickly run out of steam once at the 9500 redline but with such a sturdy pull low down and all the way up to that point the gearing can be altered to suit the demands of the power plant.

Handling wise, once the wheel is firmly back on the tarmac, the steering is super quick, almost quirky, but there is no need for a steering damper to calm things as the front tyre does it’s stuff and holds a tight line no matter. It’s the same story on the anchors as the front tyre pay’s no respect to the awesome power of the multi piston callipers as they bight into those huge discs, deciding instead to just grip and get on with it.

Yamaha YPVS ReviewThis bike likes to be doing something and, when not braking, simply begs to be hard on the gas, somehow it all just comes together. At the rear a brand new F2 shock has been acquired, the later version being a far better performer more able to handle the immense grip and corner speeds available from the latest rubber.

Of course no classic bike restorer or builder would be able to achieve much without a few good retail outlets and Trig is quick to thank those that have aided his quest for the ultimate RD, in particular Albert at his local shop, R&J Motorcycles of Coalville and the long time Yamaha expert and regular advertiser in mechanics, Motolink. Ever a keen eye on the worlds market place for the hard to find Yam parts the proprietor of Motolink, Keith is also a mine on information on most types of the breed and can well be worth a call when others fail to supply.

Another great font of information and assistance can be found on www.yamaha-rd.com, here you will find a constant source of info and inspiration for all LC matters, so get logging on and joining in.

The results of Trig and his loyal band of friends, work throughout the bike is both superb and very professional looking, with the outcome so far being an eminently usable and practical machine.

Like I stated at the beginning this is as good as it gets, with all of the right nods being made to the past and the present on the way to achieving great Joy.

Yamaha YPVS Trigs “Valve of Joy” Specifications

  • Engine; 347cc twin cylinder water cooled two stroke YPVS exhaust port and reed valve induction, 6 speed
  • Power; 58 bhp @ 9500 rpm
  • Torque; 29 ftlbs @ 8500 rpm
  • Carbs; 26mm Mikunis
  • Frame; Yamaha steel twin cradle, Metmachex box section swing arm
  • Suspension; 35 mm air assisted front forks, rising rate rear with F2 unit and remotely adjustable spring rate
  • Brakes; 2 x CBR 600 calipers 320mm Yamaha discs, Single piston floating rear caliper 220mm disc
  • Tyres; 100/80 x 18 Bridgestone BT 45 front, 120/80 x 18 Bridgestone BT 45 rear
  • Weight; 175kgs (std) “Valve of Joy” approx 165 kgs

Yamaha YPVS Special

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