For the 1983 season Yamaha published a separate service manual for the XT550 rather than reissuing the previous one. It is part number LIT-11616-XT-51, and the bike it documents carries model code XT550K.
The distinction is worth noting when shopping. The 1982 XT550 uses a different part number entirely, so a manual bought on the model name alone can turn out to be the wrong year. Read the code off your frame label first.
Coverage runs through the engine and running gear as the factory laid it out: measurement against service limits, torque specifications, valve and ignition settings, fuel system adjustment, and a wiring diagram for the harness as delivered. There is no padding, no general advice on how to use a spanner, just the procedures and the numbers Yamaha expected a dealer technician to work to on a 1983 XT550.
