1978 Yamaha GT80 Service and Repair Manual

Four seasons and two models in one binding. LIT-11616-GT-81 is the factory service manual for the GT80 across 1978 to 1981 and it covers the DT80 too. The 1978 code is GT80E.

Verify GT80E on the frame plate. Where the models or years differ, the specification pages list them separately.

Procedures run in factory order: engine removal, teardown, inspection with wear limits, then reassembly with the torque values specified. Carburation and ignition settings are given as figures. The chassis chapters handle forks, rear suspension, brakes and wheels, and the electrical section supplies the wiring diagram with component test values.

Troubleshooting is arranged by symptom. On a small two-stroke that has spent decades being maintained by eye, working from the published clearances usually solves more than another round of parts swapping.