1987-1995 Yamaha YFM350ER Moto 4 ATV Service & Repair Manual (P/N LIT-11616-07-01)

• Covers 1987–1995 Yamaha YFM350ER and YFM350ERT Moto 4 ATVs, detailing engine, chassis, and electrical system diagnostics.
• Original OEM publication P/N LIT-11616-07-01 (First edition, April 1986).
• Features over 80 exploded-view component diagrams, internal tolerance charts, valve clearance tables, and complete electrical schematics.
• Logs specific YFM350-series frame and engine serial number prefixes used for the original Moto 4 launch build.

This factory publication details exact maintenance and mechanical procedures for the Moto 4 series. It systematically breaks down engine overhauls, chassis management, and periodic inspections. Sections follow a strict teardown and assembly sequence. You will find specific inspection standards and component removal steps. Exploded-view illustrations map out every fastener and gasket required for the YFM350ER.

Reviewing all provided safety limits and torque requirements is critical before turning a wrench. Factory documentation assumes a baseline understanding of standard workshop safety protocols and proper tool operation to prevent injury or component damage.

Critical systems like carburetion, cooling, and electrical circuitry get full coverage. The organization runs from valve clearance adjustments to final drive gear lash measurements and crankcase splitting. Specialized inspection data for transmission gears, clutch housings, and steering shaft bushings gives you exact reference values for deep teardowns.

Specification and Data Preview

Technical specs run throughout the manual to establish strict wear limits for the 350 cc power plant. Intake valve clearance for the YFM350ER sits at 0.06–0.10 mm. The engine assembly data mandates a crankshaft runout limit of 0.06 mm. Final gear oil capacity is documented at 0.13 liters. Routine service work goes faster with consolidated reference values for spark plug gaps, battery charging currents, and tire inflation pressures. Cylinder head bolt torque values follow a multi-stage sequence to guarantee proper sealing during final assembly.