Yamaha KT100S Service and Repair Manual

Under Yamaha part number LIT-11626-78-70, this is the factory service literature for the KT100S, a unit carrying the model code KT100SB. The book is specific to that engine and nothing else shares it.

Coverage is mechanical and detailed: crankcase splitting, crankshaft and bearing inspection, piston and ring measurement against service limits, cylinder condition, and carburettor settings with the jetting Yamaha specified. Torque values are given for each fastener group, and the assembly order is spelled out where sequence matters.

Troubleshooting works from the symptom backward, which is the useful direction when an engine will not hold a tune. There are also the adjustment figures a rebuilder needs rather than guesses about them.

Confirm KT100SB on your engine before ordering. It is the single reference point that tells you this literature matches what is on your bench.