1985–2000 Yamaha XT350N/NC Factory Service Manual (P/N LIT-11616-04–73)

• Covers the 1985 XT350N (model code 57T) and California XT350NC (model code 56R) from starting frame numbers JYA57T00*FA000101 / JYA56R00*FA000101 and engine numbers 57T-000101 / 56R-000101; Yamaha factory publication P/N LIT-11616-04-73, 1st Edition, October 1984.
• Covers engine removal and in-frame service options, followed by disassembly, inspection, repair, reassembly, valve timing, and installation for the DOHC four-valve top end, piston, crankshaft, balancer system, clutch, six-speed transmission, shifter, kick starter, oil pump, and crankcases.
• Details the linked primary and secondary carburetors, including section views, disassembly, inspection, assembly, fuel-level adjustment, full-throttle adjustment, synchronization, and air-cleaner/crankcase-ventilation service.
• Includes front and rear wheel service, wheel-bearing replacement, hydraulic front-brake caliper and master-cylinder repair, brake bleeding, front-fork overhaul, steering-head work, rear suspension and swingarm service, and drive-chain inspection and installation.
• Provides the XT350N/NC circuit diagram, electrical component-location drawings, charging, ignition, lighting, and signal-system troubleshooting charts, system tests, exploded assembly views, lubrication drawings, cable-routing diagrams, and the related torque, capacity, clearance, wear-limit, and electrical specifications.

Engine and Maintenance Details

Yamaha identifies this publication specifically for the XT350N and XT350NC configurations. The 215-page PDF is the first-edition base manual for model codes 57T and 56R; it is not a blanket 1985–2000 XT350 publication and does not include later-model supplements. The model-identification pages keep the standard and California versions separate through their frame numbers, engine numbers, and carburetor identification marks.

The periodic inspection chapter covers the work normally performed during scheduled service: valve-clearance inspection, decompression-cable adjustment, spark-plug service, crankcase-ventilation and fuel-line checks, wet-element air-filter maintenance, engine-oil and filter service, oil-strainer cleaning, clutch adjustment, ignition-timing checks, and compression testing. Separate tables organize emission-control items and the broader maintenance and lubrication schedule. Chassis checks cover brake condition and adjustment, drive-chain care, cable lubrication, control pivots, steering bearings, wheel bearings, tires, spokes, suspension, battery electrolyte, headlight aim, and circuit-breaker inspection.

The engine-overhaul chapter goes well beyond routine maintenance. It begins with removal preparation and identifies four major jobs that can be handled with the engine still in the frame: piston, clutch, carburetor, and AC magneto service. Full teardown coverage follows for the camshafts, cylinder head, cylinder, piston, clutch, primary drive and balancer gears, cam-chain components, kick-start mechanism, oil pump, shift system, CDI magneto, crankcases, transmission, bearings, and oil seals. Inspection and repair sections add factory wear limits and checks for the valves and seats, camshaft and chain, crankshaft and connecting rod, gears, clutch pack, shifter, balancer drive, and crankcase assemblies. Reassembly includes crankshaft and balancer installation, transmission and shifter setup, crankcase closing, cam timing, final adjustment, and engine remounting.

Several cautions show why the factory sequence matters. After oil and filter work, the manual requires confirmation of oil flow; continued running without it can seize the engine. During cam-timing assembly, excessive camshaft rotation can damage the piston and valves. Before the crankcase screws are torqued, transmission operation must be checked so a shift-assembly problem is not trapped inside the closed cases.

Carburetion, Chassis, and Electrical Repair

The carburetion chapter is specific to the XT350’s staged primary/secondary setup rather than a generic single-carb layout. It provides a labeled section view and exploded assembly, then covers disassembly, component inspection, reassembly, float-level setting, full-throttle linkage adjustment, carburetor synchronization, and the air-cleaner and crankcase-ventilation system.

Chassis repair coverage includes spoke-wheel inspection, bearing replacement, rear-wheel and drum-brake service, front disc-brake pad replacement, caliper and master-cylinder disassembly, hydraulic bleeding, fork removal and internal overhaul, steering-head bearing adjustment and replacement, rear shock and linkage handling, swingarm removal, and drive-chain inspection. The manual warns that fork oil must be kept off the front brake and that the nitrogen-charged rear shock must not be opened, heated, or damaged.

Electrical diagnosis is organized by system. The XT350N/NC circuit diagram and component-location drawings lead into charging-system fault tracing, battery and generator checks, rectifier/regulator diagnosis, ignition troubleshooting for weak or missing spark, ignition-control circuit operation, neutral- and sidestand-switch checks, CDI-unit testing, and separate lighting and signal-system charts. The latter isolate headlight and high-beam, turn-signal, brake-light, neutral-light, horn, and switch faults rather than leaving the reader with only a wiring schematic.

Specification Highlights

The appendices consolidate general and maintenance specifications for the engine, chassis, and electrical system. Coverage includes component-specific torque tables, approved lubricants and fluids, capacities, valve and bearing clearances, cylinder, piston, and ring limits, clutch and transmission inspection data, fork and shock specifications, wheel and brake wear limits, chain settings, ignition and charging test values, and a general fastener-torque chart.

A dedicated special-tool section identifies Yamaha tools and part numbers used in the repair procedures. Examples include the universal clutch holder YM-91042, flywheel puller YM-01189 with attachment YM-1382, crankcase separator YU-01135, crankshaft installing set YU-90050, front-fork seal driver YM-08010, and electrical tester set YU-33260. Particularly useful drawings include the carburetor section view, engine and transmission exploded assemblies, XT350N/NC circuit diagram, electrical component views, lubrication diagram, and three-page cable-routing layout.

Motorcycle repair involves fuel, hot engine parts, hydraulic brakes, pressurized suspension components, and live electrical circuits. Support the motorcycle securely and follow Yamaha’s model-specific cautions and test conditions for the 57T or 56R configuration being serviced.