Yamaha RD350 The Story
Miniature superbike
One of my neighbours had an early Yamaha 250, probably a DS6. It was painted a very contemporary purple with white pin-striping and was my first contact with two stroke twins of any kind. Until the RD350 appeared I wasn't interested in Yamaha's smaller twins as they were part of the generation of bikes that had been well and truly swept aside by the first generation of Japanese superbikes.
However, the situation changed when the RD350 appeared and began to gain a reputation as a giant slayer, easily dispatching bikes twice its size in drag races and through the twisties. Performance, reliability and reasonable build quality helped establish the RD as a bike to be taken seriously. It might not have had the sheer power or torque spread of bigger machines but when it hit the powerband it was time to hang on and how! And it would do it day after day. The bike was also very flickable and reacted instantly to steering input, no doubt the product of low weight and good mass centalization.
For Yamaha the RD represented a major technical leap over its previous generation of piston port twins. by introducing reed valves to control induction. This change permitted port timing optimised for torque spread and generally improved the civility of the powerplant and made it more pleasant to use.
The RD350 was never very common in NZ where the most popular bikes around were big Japanese and British fourstrokes. There was some resistence to two strokes, they weren't "serious enough" for the true biker and were only fit to serve as rungs on the way up the capacity ladder to a real bike. Also working against higher RD sales was its capacity, a 350cc just wasn't big enough for the serious biker. As soon as you could you flogged your 350 and moved on to something bigger. This was a pity as the RD was a miniature superbike in all but name, offering an intense and exhilarating ride for very little money.

Of course, as with any bike, there were a few flies in the ointment. Fuel consumption, when you rang its neck, meant finding a petrol station after a hundred miles or so. But this was probably a good thing as your butt and fingers would be going numb by then from the vibration coming through the tank and bars. Another annoyance was the idiot light that lit up every time you hit the brakes, this was not so much of a pain during the day but at night it was a needless distraction and probably outweighed the potential benefits of knowing the tail-light bulb had blown.
Exceptional though the bike was it didn't escape some of the common bugbears of Japanese bikes of the time, notably the duration of the chrome and paintwork.
Over time the black finish on the barrels would start to flake off leaving the engine looking old before its time and the metalflake on the '73 model would soon fade under the ozone saturated Kiwi sun. From 1973 when the trouble-ridden TX750 was dropped until the bigger 400 appeared 3 years later the RD was the only true sports bike in the Yamaha range. This was a demanding role for a "lowly" 350 but one the bike carried off admirably. And of course the bike paved the way for the RD400, perhaps the epitome of the seventies Japanese sporting two stroke.
Today the little RD has taken its place amongst the superbikes of the period and justifiably so, particulary if you compare it to its comtempraries, none of which had its  all round competence and ability. And, before I forget, it was a great looking little machine too!