1987 Yamaha YFM225 Moto 4 Owner's Manual (P/N LIT-11626-05-85)

• Official Yamaha factory publication (P/N LIT-11626-05-85, 1st Edition, November 1986).
• Features 32 technical diagrams, two specific torque-spec reference tables, and 14 maintenance intervals.
• Represents the original source document utilized for the YFM225T launch build.

Operational Data and Maintenance Outlines

This factory manual details the exact parameters required for routine off-road upkeep, control function identification, and daily operation of your Moto 4. For technicians and DIYers, the immediate value lies in having rapid access to the factory setup for the 12V electrical system, including accessory lead connections and the proper utilization of the auxiliary DC terminal on the front bumper. Instead of guessing, you get the exact break-in cycles and proper engagement procedures for the high, low, and reverse transmission ranges. Working on vintage ATVs carries inherent risks; always verify the vehicle is securely supported and the engine is cool before referencing these maintenance schedules. The document also clarifies the correct usage of the decompression lever for emergency starts and outlines visual checks for gear oil, battery fluid levels, and tire pressure management.

Specification Highlights

Quickly finding the right numbers is crucial when you have an engine apart on the bench. Detailed technical tables provide critical values for assembly, clearly identifying the torque specifications for the spark plug at 17.5 Nm and wheel nuts at 32 Nm. Exact fluid capacities are mapped out, requiring 1.5 L for periodic engine oil changes and 0.23 L for the final gear case. To maintain efficient ignition performance under varying load conditions, the spark plug gap must be set strictly at 0.6–0.7 mm. The reference data also establishes factory tire pressure baselines at a recommended 20 kPa for both the front and rear, alongside the specific identification of vital grease points to keep the suspension articulating smoothly.