Antique, Vintage, and Historic Parts for the Yamaha RD400

The RD400 and a few related motorcycles were only produced for a few years, which makes them sought-after bikes by some Yamaha collectors. Yamaha produced RD400 bikes from 1975 until the 1980 model year. Even though these bikes are a vintage standby, several aftermarket manufacturers focus on producing parts that perform like antique or vintage original components.

What speeds must RD400 parts be certified to withstand?

None of the Yamaha RD400 bikes that were on sale from 1976 to1980 could exceed 107 miles per hour. Unless youve done a racing rebuild, you wont have to use parts certified to go beyond this speed. Some restoration crews have opted to use newer racing components. If this is the case, then youll find racer supply parts that work equally as well as those that were originally installed on these classic Yamaha motorcycles.

Should you use classic original parts when restoring Yamaha RD400 motorcycles?

Yamaha didnt put replacement parts on sale for much longer after they discontinued the Yamaha RD400. This can make it hard to find rear wheels and other parts that are fully original to these bikes. Whether you want to use genuine vintage components or aftermarket parts is up to you. You shouldnt be afraid to combine them on your 400 series ride as well. You might want to have an untouched engine but a new rear brake assembly. These kinds of differences are not visible to the naked eye and do not undermine the vintage appearance of your bike.

What makes the 1979 version of the 400 so different?

The RD series received capacitor discharge electronic ignition units in 1979. Yamaha also installed thinner spokes on that years equipment. The foot peg was moved and several minor engine modifications were made that year as well. If you see an RD with something called a CDI box attached to it, then youre actually looking at one that features this electronic igniter.

What kind of stoppers did the stock units come with?

Both stock stop units featured front and rear discs. This gave the bike the ability to come to a standstill after finishing up a quarter-mile from a standstill in around 14.01 seconds. These stoppers were designed to stand up to a certain amount of mileage before burning up. Most aftermarket parts are manufactured to match the stock specifications.

What kind of frame do 400 series rides feature?

All of the various versions of the 400 series feature a tubular twin cradle frame. This helps to distribute the weight of the air-cooled two-stroke straight twin motor without making one side of the frame feel heavier than the other. This additionally helps to reduce the amount of vibration when riding at highway speeds.