1986 Yamaha IT200S Owner's Manual and Service (P/N LIT-11626-05-15)

• Exact factory coverage: The 125-page PDF reproduces Yamaha’s factory manual for the 1986 IT200S competition off-road motorcycle, model code 1TY. The identification data lists VIN *JYA1TY00GA015101 and engine starting number 43G-015101. Publication P/N LIT-11626-05-15**, First Edition, October 1985.

• Top-end and induction repair: Covers VM34SS Mikuni carburetor removal, disassembly, inspection, float service, and standard jetting; Y.E.I.S. chamber and hose checks; reed-valve inspection; muffler maintenance; and cylinder head, cylinder, piston, and ring teardown, measurement, and assembly.

• Clutch, transmission, and bottom-end work: Details clutch-pack inspection and mechanism adjustment, primary drive and kick-starter service, shifter checks, engine removal and mounting, crankcase separation, bearing and oil-seal inspection, six-speed transmission service, crankshaft checks, and crankcase assembly.

• Brakes, steering, and suspension: Includes wheel, sprocket, and chain service; front-disc caliper and master-cylinder repair; hydraulic brake bleeding; rear-drum inspection; front-fork oil, seal, bushing, and damper-rod work; steering-head service; Monocross rear-shock settings and removal; and swingarm-linkage inspection.

• Electrical diagnosis and troubleshooting: Provides no-spark and weak-spark fault isolation, CDI magneto source- and pickup-coil tests, ignition-coil and engine-stop-switch checks, lighting output and regulator diagnosis, plus engine, clutch, transmission, brake, steering, and wheel troubleshooting charts.

• Factory reference material: Exploded views identify the carburetor, clutch, transmission and shifter, front disc brake, front fork, and Monocross rear shock assemblies. The PDF also supplies wiring and cable-routing diagrams, maintenance schedules, torque tables, capacities, inspection limits, suspension data, and electrical test specifications.

Yamaha built this volume as both an owner’s reference and a repair manual. The opening chapters cover controls, premix and transmission-oil requirements, pre-operation checks, break-in, lubrication, cleaning, and storage before moving into workshop procedures. Its sequential service format is suited to experienced owners and working mechanics who can use precision measuring equipment and model-specific pullers, holders, and drivers. The manual identifies the IT200S as a competition-only machine and not legal for street operation.

Engine and Drivetrain Detail

The engine chapters go well beyond routine maintenance. Carburetor coverage identifies standard and optional jet components and their Yamaha part numbers, while the top-end sections provide inspection criteria for cylinder-head warpage, cylinder bore condition, piston clearance, ring gaps, and piston-pin and small-end condition. Clutch plates, springs, push rod, kick mechanism, gears, shift forks, guide bars, shift cam, transmission shafts, bearings, seals, and crankshaft are each tied to inspection or repair criteria.

Major service-tool requirements are identified by name and P/N, including the YU-01135 crankcase separator, YU-90058/YU-90060/YU-90063 crankshaft installer set, YM-33962/YM-01326 fork-cylinder tools, and YU-03112 Yamaha Pocket Tester. Rotor, clutch, steering, and fork-seal tools are also specified. A crankcase warning explains that forcing uneven separation or striking a gasket surface can damage the case halves and sealing face; the assembly section also calls for transmission operation to be checked before the case screws are tightened.

Chassis, Brake, and Suspension Detail

Brake coverage distinguishes the hydraulic front disc from the mechanical rear drum. The front section addresses pad replacement, caliper piston and seal service, master-cylinder inspection, bleeding, disc checks, and fluid-handling precautions. Wheel chapters add axle, bearing, spoke, rim-runout, brake-drum, sprocket, chain, speedometer-drive, and installation checks.

The fork chapter covers oil replacement, spring options, oil-level and air-pressure data, complete removal and disassembly, damper-rod and guide-bushing inspection, seal installation, and reassembly. It specifically warns that bottoming the inner tube during guide-bushing removal can damage the oil-lock piece. Steering-head bearing service and swingarm, relay-arm, connecting-rod, collar, bushing, and seal inspection round out the chassis repair coverage.

Scope and Safety Notes

Detailed carburetor and suspension race-tuning procedures are outside this publication; Yamaha directs the reader to the separate Race Preparation and Tuning Manual. The De Carbon rear-shock section covers settings, handling, removal, spring removal, and installation, but not internal shock overhaul or nitrogen charging. Because the remote reservoir is pressurized, the manual prohibits disassembly of the cylinder, tank, hose fittings, and related fasteners and assigns disposal of a worn or damaged unit to a Yamaha dealer.

Crankshaft removal, measurement, and installation are included, but crankshaft repair beyond the listed tolerances is also referred to a Yamaha dealer. These limits matter when choosing this manual for a full competition rebuild.