The general advice from those who know is don‘t buy a secondhand two stroke. Indeed, those brought up in the sixties and seventies would tell you not to buy a new stroker! So there I was, ignoring all that accumulated knowledge, just 18 years old, a couple of hundred notes in my pocket, looking at this dodgy old 1974 Yamaha RD200. Before I knew what I had done I had handed over the money and buzzed off down the road on my new pride and joy!
Well, it seemed like a good idea at the time. I had just passed my test on a borrowed bike and needed some cheap wheels to gain some experience, not to mention kicks. The Yam had started first kick, wailed nicely and everything appeared to work, although the owner declined to give me a test ride. So that first ride was all the more interesting. In retrospect I could easily have been ripped off, but the 59000 miler got me the 40 miles home without incident.
The Yamaha was not much faster than the 12hp TZR on which I took my test. The twin cylinder engine buzzed to a surprising degree and the presence of reed valves did not help, as then claimed, in the production of low speed torque. 5-6000 revs were needed before it began to motor in anything approaching a reasonable manner. Flicking the bike into the red in the lower gears was the only way to get the speedo past 70mph in fourth. Several attempts were made to do more than 80mph but they all failed dismally.
Handling behaviour was reminiscent of an old Honda 50 I once owned, bouncing about on soft suspension, scraping the stands and exhaust in corners and generally wallowing when flat out, my head down on the clocks and arms waving about above my ears.
The TLS front brake was a real tear jerker. It either grabbed on viciously or refused to work altogether. The linings and shoes were all shot to pieces, looked like someone had attacked them with an hatchet. A CB175 wheel a breaker sold me for a fiver fitted in with a bit of bodging, about ten times better but took three weeks to track down. In which time I crashed the bike three times, solely due to that damnable brake. New, it was probably ace.
The first crash was the most serious. On a damp road that the first rainfall of the summer had turned treacherous. The front wheel locked solid, the tyre just skidded away from under the bike and before I knew what had hit me I was down on the road.
The exhaust all but burnt a hole in my leg and the crack my kneecap took gave me a clear picture what it would be like to be a Mafia victim. I still twitch violently whenever I think about it, which is all too often given the dubious nature of the RD's chassis. The other two crashes were low speed slides in which I fell clear of the machine. No serious damage was sustained by the Yamaha.
Gradual loss of power led me to the conclusion that the silencers and top end of the engine needed a decoke. Various bolts broke off when I tried to undo them and the baffles were so gunged up they refused to come out until I poured petrol down the silencers (after removing them) and set them alight. This made the decoke process easier but ruined the chrome finish. The piston tops and combustion chambers were cleaned up, polished to a mirror finish.
The reassembled motor finally fired up after a bump start, refused to run cleanly, down to a massive leak in the carb inlets. That fixed with Araldite, performance was back to the previously sluggard levels. I disassembled the motor again and took a file to the ports and attached some expansion chambers meant for a YPVS. The jets were so far out the machine refused to run, had to go up three sizes all round. The machine was as dead as a dodo below 7000rpm then screamed crazily right through the red zone, going off the rev counter.
Vibration levels were as amazing as the kick in the guts, and the demented wasp like sound flicking off the surrounding neighbourhood at about 200 decibels. The way the front wheel leapt off the ground was mind warping and an indicated 100mph scared the hell out of me, the chassis giving a strong impression of falling apart under me.
In retrospect, a bloody silly thing to do to such an old engine but for 2800 miles extreme fun was enjoyed. Then, naturally, the motor failed, after one 125 mile blast, melting together its various components until its only useful function would have been as a piece of modern, demented sculpture. Well, why the hell not, artists get away with a lot worse in the name of art, don’t they? There followed a period of total neglect of the RD. It wasn't until a mate of a mate of a mate was tracked down with a crashed RD200, rotting away at the back of his garage, plus a spare box of engine bits that any hope was available.
The motor was seized but a few hammer blows and a spare set of pistons soon sorted that. I decided to stick with a stock engine this time, once bitten, etc. After about a week’s work the RD emerged once more from my shed to take on the world.
This composite Yamaha was dog slow, 70mph flat out but surprisingly economical at 60mpg (the tuned one had been doing about 25mpg), although it needed a new set of spark plugs every 2500 miles and dedicated feeding of the oil tank. I lopped along on it well enough, a reliable commuter that did the 18 mile daily chore without complaint for the next four months. I was quite pleased as I had only paid sixty notes for the crashed machine. I did have to close my eyes to the fact that I was often buzzed by dorks on mopeds, who would often speed past having modded their motors to do much more than the proscribed 30mph.
Gradual loss of speed convinced me that a decoke was necessary... I couldn’t resist taking a file to the ports and fitting the spannies and re-jetted carbs. I never learn, the motor lasted exactly 436 miles before the main bearings started rumbling. A rebuilt crankshaft, new barrels and pistons later, I was back on the road.
With stock but decoked exhaust and standard carbs, this was arguably the best version of the RD I had managed. The speedo needle quivered around the 85mph mark (down hill, following wind, etc), fuel stayed constant at around 60mpg and acceleration was almost fierce in the lower gears.
No more could tuned mopeds be a cause for great loss of face and embarrassment. This improved performance convinced me that I could burn off restricted TZR125s. Just possible down the straights, the difficulties emerged when the road became twisty. Gradual deterioration of the already poor and apparently original suspension meant that the front wheel walked away from the machine in a series of disturbing pogo actions whenever the bike was banked over in an ever so slightly bumpy bend (which given the state of our roads was every time). The result was that she was dead easy to fall off.
The solution came at the breakers, as usual, in the form of a complete TZR250 front end. It was not that brilliant as the smaller front wheel gave the machine an aggressive cant forwards and a tendency to fall rapidly into bends... but it was about a hundred times more stable. As soon as I'd sorted the front, after a fashion, the rear swinging arm bearings went. 20 miles later one of the shocks broke, but it had done at least 100000 miles so I could not really complain.
The general condition of the chassis was, not surprisingly, poor, in desperate need of the attention of a spray gun but not likely to get it. Hammerite was half heartedly applied where deemed necessary to surprising effect. Other imponderables included lack of sidepanels, broken kickstart lever, missing air filters and a seat that was more foam than cover (soaking up the water like a sponge).
A change of employment meant a sudden, large rise in income which necessitated trading in the little Yamaha against a new FZR600. The RD was valued at £750, but that was off the recommended price off which I would probably have got a £750 discount if I was paying cash. The RD had impressed me more than it depressed me, enough to stick with the marque but take more note of the advice about buying strokers.
Adrian