2004–2006 Yamaha Bruin 350 (YFM350BAT) 4x2 Owner's Manual (P/N LIT-11626-18-10)

• Yamaha Bruin 350 manual set combining YFM350BAT owner information with YFM350AS service coverage and its required YFM400FAR base manual.
• Engine repair coverage extends from cylinder-head and valve work to crankcase separation, crankshaft replacement, and balancer-gear alignment.
• V-belt automatic transmission sections cover primary and secondary sheave disassembly, centrifugal-clutch inspection, and internal transmission removal and reassembly.
• Shaft-drive procedures include middle-gear shim selection, universal-joint service, and rear final-drive disassembly, gear positioning, and backlash adjustment.
• Front hydraulic-disc and rear drum brake repair covers master-cylinder and caliper service, brake bleeding, shoe inspection, and pedal/lever adjustment.
• Electrical fault-finding covers ignition, starting, charging, and lighting, with YFM350AS wiring and dedicated oil-temperature warning and cooling-fan circuits.

Manual Set and Model Coverage

The set contains 656 pages across two PDFs. The owner’s manual is a 173-page PDF, publication LIT-11626-18-10, first edition March 2004.

The 483-page service PDF combines the 366-page YFM400FAR Service Manual, LIT-11616-16-02 (April 2002), with the 117-page YFM350AS Supplementary Service Manual, LIT-11616-17-33 (August 2003).

The supplement identifies model code 5WH1 and must be used with the base manual—not as a standalone repair guide. Its air-cooled SOHC single-cylinder engine and oil-cooler coverage differ from the liquid-cooled 400 configuration. The base manual’s front differential and 2WD/4WD selector chapters belong to the 400 configuration, not the 350.

Engine, Carburetor, and Chassis Service

The 350 supplement details oil-pump disassembly, oil-cooler and fan removal, and crankshaft installation. Cylinder and valve-train service includes piston/ring inspection, valve-guide and seat work, and cam-chain timing checks. Tool references include the YM-04134 sheave spring compressor and YU-90050 crankshaft installer set.

Carburetor repair covers the Mikuni BSR33, including float and needle-valve inspection, diaphragm checks, fuel-level measurement, and idle adjustment. Steering and suspension sections address tie rods, steering-stem bearings, ball-joint replacement, toe-in, and swingarm removal and inspection.

Yamaha flags insufficient shaft-drive gear lash as a cause of gear-tooth damage. The front-brake sections also warn that unsuitable solvents can swell and distort internal rubber seals.

Wiring Diagrams and Diagnostic Charts

The Oil Flow Diagrams trace lubrication through the engine, filter, and oil cooler. Cable Routing drawings identify harness, hose, and control-cable paths. The Signal System Circuit Diagram and Cooling System Circuit Diagram accompany checks of the thermo unit, diode, fan relay, and fan motor. The full YFM350AS Wiring Diagram provides wire-color identification and component references.

Diagnosis goes beyond symptom lists: the service sections supply coil-resistance tests, charging-voltage checks, switch-continuity tables, and starter-motor inspection limits.

Operation and Safety Protocols

The owner’s manual explains the main switch, drive select lever, speed limiter, and fuel system management. Pre-operation inspection requirements cover brake condition, tires, fluid levels, and throttle operation. Riding guidance addresses steep climbs, descents, and rough terrain, alongside loading and transport precautions.

Routine owner maintenance includes oil/filter changes, final-gear oil service, air-filter cleaning, spark-arrester cleaning, and storage preparation. A troubleshooting chart separates basic fuel, compression, ignition, and battery checks.

Always review these OEM safety guidelines prior to operation or servicing, particularly the precautions for supporting the ATV and working on its brakes.

Technical Specifications and Load Limits

The reference sections provide component-specific tightening torques, lubrication requirements, fluid capacities, engine clearances, and wear limits. Load guidance distinguishes front and rear carrier limits from overall vehicle load, trailer-pulling capacity, and hitch tongue load, rather than treating carrier ratings as the ATV’s total payload.