The RD400 is a

two-stroke A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a Thermodynamic power cycle, power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being comple ...

air cooled Air-cooled engines rely on the circulation of air directly over heat dissipation fins or hot areas of the engine to cool them in order to keep the engine within operating temperatures. In all combustion engines, a great percentage of the heat ge ...

six-speed

motorcycle A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...

produced by

Yamaha Yamaha may refer to: * Yamaha Corporation, a Japanese company with a wide range of products and services, established in 1887. The company is the largest shareholder of Yamaha Motor Company (below). ** Yamaha Music Foundation, an organization estab ...

from 1976 until 1979. It evolved directly from the

Yamaha RD350 The RD350 is a two-stroke motorcycle produced by Yamaha from 1973 to 1975. It evolved directly from the piston port (pre-reed valve intake tract), front drum-braked, five-speed Yamaha 350 cc "R5". The engine is an air-cooled, parallel twin, six- ...

The 350 evolved into the RD400C in 1976, the "D" and "E" in '77–'78 and the final model, the white 1979 RD400F. (The model year for the first RD400, which was sold in the U.S. in the summer of 1975, was 1976.) The RD series was discontinued due to new emissions rules in the late 70's and eventually all road motorcycles were 4-stroke engines and did not burn oil with the fuel mixture to lubricate the pistons. The RD400 came with a unique self-cancelling light system that measured wheel rotations after the indicator lights were enabled. Also, for convenience, the RD did not require pre-mix fuel in the tank since it came with a 2-stroke oil pump which delivered the appropriate amount of oil when the throttle was engaged. The brakes were single disc front and rear. It could complete a standing quarter-mile in 14.01 seconds. The RD400C was the first motorcycle by a major manufacturer to be fitted with cast wheels. In 1979 the RD was fitted with a capacitor discharge electronic ignition (CDI) unit, as well as thinner spoked cast wheels, a new foot peg position, and some minor engine modifications.

References

{{reflist, refs= {{cite magazine , last=Gingerelli , first=Dain , date=July 1993 , title=RD Days , url=https://magazine.cycleworld.com/article/1993/7/1/rd-days , magazine=

Cycle World ''Cycle World'' is a motorcycling magazine in the United States. It was founded in 1962 by Joe Parkhurst, who was inducted to the Motorcycle Hall of Fame as "the person responsible for bringing a new era of objective journalism" to the US. ''Cyc ...

, pages=76–86, location= , publisher= , access-date=

RD400 The RD400 is a two-stroke air cooled six-speed motorcycle produced by Yamaha from 1976 until 1979. It evolved directly from the Yamaha RD350 The 350 evolved into the RD400C in 1976, the "D" and "E" in '77–'78 and the final model, the white 19 ...

Motorcycles introduced in 1975 Two-stroke motorcycles Motorcycles powered by straight-twin engines Standard motorcycles

See also

References