Yamaha RD350

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1973 Yamaha RD350 in red.jpg
Yamaha RD350
Manufacturer
Also called RD350 (6-speed), RD 350 (6-speed), RD350 (5-speed), RD 350 (5-speed), RD350LC YPVS (reduced effect), RD 350 LC YPVS (reduced effect), RD350LC YPVS, RD 350 LC YPVS, RD350 (reduced effect), RD 350 (reduced effect), RD350F (reduced effect), RD 350 F (reduced effect), RD350N (reduced effect), RD 350 N (reduced effect), RD350N, RD 350 N, RD350R YPVS, RD 350R YPVS, RD350LC, RD350F, RD 350 LC, RD 350 F, RD350B, RD 350
Production 1973 - 1975
Class Naked
Predecessor Yamaha R5
Successor Yamaha RD350LC, Yamaha RD400, Yamaha RZ350
Engine
350cc twin, two-stroke
Bore / Stroke 64.0mm x 54.0mm
Compression ratio 6.6:1
Top Speed 116 mph (187 km/h)
Horsepower 48.95 HP (36.5 KW) @ 9000RPM
Air Filter K&N YA-0700 `73-75[1]
Spark Plug NGK B8HS 73-75
Battery YUASA 12N5-5A-3B 73-75
Transmission Gear box: 6-speed
Final Drive: chain
Final Drive Chain: 530x92
Front Sprocket 15T
Rear Sprocket 40T
Brakes Front: single disc
Rear: drum
Front Tire 90/90-18
Rear Tire 110/80-18
Weight 162.0 kg (wet)
Fuel Capacity 4.49 Gallon (17.00 Liters)
Related Yamaha RD200
Yamaha RZ350, Yamaha TZ350
Competition Kawasaki S2
Suzuki GT380
Manuals Service Manual

Brochures ·


The Yamaha RD350R was a 350cc twin cylinder two-stroke street motorcycle produced by Yamaha between 1973 1975. It could reach a top speed of 116 mph (187 km/h). Claimed horsepower was 48.95 HP (36.5 KW) @ 9000 RPM.


History[edit]

1973 Yamaha RD350 front angled

The RD350 was well developed for the time, air-cooled, two cylinder, Autolube equipped (automatic oil injection), 6 speed (in some markets, such as the UK, the first model was sold in 5-speed form) two-stroke, street motorcycle produced by Yamaha. It was the premier sport lightweight of the early 70's. It was evolved from the front drum-braked, 5 speed Yamaha 350cc "R5".

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). 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. 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. Many enthusiasts would convert their RD350 to specifications similar to a TZ350, such machines would then be reasonably competitive in club racing events.

The bike made about 32 to 35 rear-wheel HP - 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 so-called "cleaner running" RD400C in 1976, the "D" and "E" in 77-78 and the final model, the white 1979 RD400F.

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 etc"

  • XS = 4 stroke tourer
  • XV = 4 stroke V
  • DT = 2 stroke trail
  • RD = 2 stroke road

The PR guys jumped on the race developed band wagon.

The bike was a very snappy performer and many new riders purchased the bike. The combination of a stiff suspension, abrupt power delivery, very powerful brakes and inexperienced riders was not a good one. It was regarded as being "too fast" for most new riders.

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. The US was the first country to impose extremely tight emission standards for new vehicles.


  1. Uncontrollable 1st gear wheelies in the hands of careless riders were the biggest problem.



Engine[edit]

The engine was a air cooled twin, two-stroke. A 64.0mm bore x 54.0mm stroke result in a displacement of just 350.0 cubic centimeters. Fuel was supplied via a port control. Yamaha did make a liquid-cooled variant in the Yamaha RZ350. The Yamaha Banshee engine was based on a very similar design.

Drive[edit]

The bike has a 6-speed transmission.

Chassis[edit]

It came with a 90/90-18 front tire and a 110/80-18 rear tire. Stopping was achieved via double disc in the front and a single disc in the rear. The RD350R YPVS was fitted with a 4.49 Gallon (17.00 Liters) fuel tank.


1973[edit]

1974[edit]


1975[edit]



In Media[edit]


See Also[edit]


External links[edit]

References[edit]

  1. 2019 K&L Supply Co Catalog. K&L Supply Co. 2019. 




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