The Yamaha RD400 is a lightweight, two-stroke motorcycle produced by Yamaha from 1976 to 1979. Known for its sporty design and agile handling, it features a 399cc engine that delivers impressive power for its size. The bike is popular among enthusiasts for its performance and classic styling. With a top speed of around 110 mph, the RD400 was designed for both street and racing use. It includes a six-speed transmission and a distinctive twin-cylinder layout, making it a favorite among riders looking for a fun and engaging riding experience.