1989-1991 Yamaha YFM250 Moto 4 ATV Service Manual (P/N LIT-11616-06-62 / LIT-11616-YF-25)

• Official OEM publication for the 3GH model series (LIT-11616-06-62 / LIT-11616-YF-25), first edition August 1988
• Covers routine maintenance and complete overhauls for the 1989–1991 ATV models
• Packed with technical diagrams, torque specifications, and exploded-view illustrations for all engine and chassis systems

Engine and Drivetrain Specs

This service manual covers everything from routine maintenance to full teardowns for the air-cooled 229.6cc SOHC engine and five-speed transmission. The opening sections cover machine identification, serial number locations, and essential service tools. From there, you get the factory periodic maintenance schedule, which maps out exact intervals for spark plug inspection, valve clearance verification, and lubrication. It also breaks down engine removal, overhaul tolerances, and clutch inspection limits, alongside detailed shaft drive and gear lash measurements.

Chassis and Electrical Data

Get direct access to OEM baselines for the front and rear braking systems, including cable free-play adjustments and shoe thickness wear limits. The electrical section maps out complete circuit wiring diagrams, starter relay resistance, and charging system output values. Important factory specifications—such as the 0.05–0.09 mm intake valve clearance, the 1,450–1,550 RPM idle speed, and the 180–220 ohm magneto pickup coil resistance at 20°C—are clearly detailed.

Working on ATVs involves heavy suspension components and electrical systems. Always review the factory safety guidelines and specific torque settings outlined in this manual before starting any major teardowns. This 112-page reference provides the exact data and baseline metrics needed to maintain and service your machine safely and accurately.