1977 Yamaha RD400 Service and Repair Manual

The 1977 RD400 carries the model code RD400D. Its manual is Yamaha part number LIT-11616-RD-40, the same book that serves the model from 1976 to 1979.

Because all four years live under one cover, the specification tables are where the D model separates from its neighbours. Look for that code before you take a clearance or a jetting figure as yours; the procedures themselves are shared across the range.

The structure is conventional factory layout. Maintenance and adjustment specifications come first, so a tune-up can be done without opening the engine. Then the engine work proper, from removal through the top end to the crank assembly, clutch and transmission, each step with its torque value. Autolube, fuel and ignition follow. The chassis chapters give service limits for forks, swingarm, wheel bearings, brakes and drive chain, and the electrical section has the wiring diagrams.

Written for a technician, not for a showroom.