Yamaha RD350
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The RD350 was a motorcycle produced by Yamaha. It was the premier sport lightweight of the early 70's and was evolved from the piston port (pre-reed valve intake tract), front drum-braked, 5 speed Yamaha 350cc "R5".
Well developed for its time, it featured a reliable aircooled, parallel twin, 6 speed (in some markets, such as the UK, the first model was sold in 5-speed form), reed valve equipped intake tract two-stroke engine. It was in production as a purple with white side details RD350 (1973), the RD350A, simple purple tank with "Yamaha" on the tank and the orange with white, 1975 (RD350B). The B model (in the UK at least) also featured a silver and black colour scheme.
All models were equipped with "Autolube" automatic oil injection, relieving the user from the need to be mixing gasoline and two-stroke oil.
Rim sizes were 18" WM2 (1.85") front and 18" WM3 (2.15"), both being of chromed, wire spoked steel construction. In the UK, rim sizes were 1.60 front and 1.85 rear.
Brakes were: single front disc brake and a rear drum brake, which Cycle Magazine described the combination as the best in its class.
The frame dimensions of the street 350 were very similar to the famous Yamaha TZ250 and TZ350 series factory road race bikes, differing mainly in weight and front fork rake - the RD being ~27 degrees and the TZ being ~25 degrees. The frames appeared similar, side by side, with the street frame adorned with many brackets for the street equipment. The weight difference was substantial though, with the street going RD frame weighing almost twice as much as the "TZ" roadrace race frame.
The stock bike made about 32 to 35 true rear-wheel HP at about 7500 rpm - very fast then, but as of 2006, some 600cc bikes now make about 100 HP. A contemporary of the RD was the Kawasaki H2 750cc Triple, said to make 72 to 75 true HP (tested by Cycle Magazine at 55bhp).
The 350 evolved into the more refined and cleaner running RD400C in 1976, the "D" and "E" in 77-78 and the final model, the white 1979 RD400F.
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[edit] The RD Name
There was a myth that RD stood for "Racing Death" and "Road Death" and that it was the Japanese revenge for the atomic bombings of Hiroshima and Nagasaki, as it claimed the lives of many US riders, but this is pure fiction (according to Japanese representatives). It was thought by some RD stood for "race developed." But a long time Yamaha mechanic recently dispelled this myth on the UK Yamaha RD forum, this is his explanation and he has worked with and raced them since the seventies: "We always understood it to be a series of letters that explain the bikes make up and function two stroke twin." The RD was a gas guzzler that would deliver anywhere between 6 - 24 KMs to a litre.
XS = 4 stroke tourer
XV = 4 stroke V
DT = 2 stroke trail
RD = 2 stroke road
[edit] Popularity
The bike was a very snappy performer and was popular with beginner riders. However, the combination of a stiff suspension, relatively abrupt power delivery and very powerful brakes to the inexperienced riders led it to being regarded as being "too fast" for new riders (uncontrollable 1st gear wheelies in the hands of careless riders were not an uncommon problem). Its good performance, light weight, and easy maintenance made it a world favorite but it ultimately suffered at the hands of increasingly stringent noise and tighter emissions standards in the US market and changing consumer appeal.
[edit] The RD in India
The RD350B was manufactured in India between 1983-1989 under the brand name Rajdoot 350. This motorcycle was detuned from the original 39 crankshaft bhp to 30.5 bhp and then finally 27 bhp in the quest of better economy. This bike has a great cult status in India and is seeing great resurgence with the youth of today.
