1987-1988 Honda TRX125 Fourtrax Factory Service Manual (P/N 6101000)

• Covers the Honda TRX125 Fourtrax, featuring the 4-stroke 124.8 cc engine, 5-speed constant-mesh transmission, and wet multi-plate automatic clutch
• Official OEM publication (P/N 6101000) providing direct factory specifications for the 1987 and 1988 model years
• Contains 193 pages of technical data, including engine assembly illustrations, electrical wiring schematics, and torque tables for over 40 chassis and engine components
• Documents the single-cylinder configuration and reverse-gear transmission mechanics for accurate diagnostic and shop work

Technical Structure and Contents

This service publication details the exact procedures for machine upkeep, diagnostics, and complete teardown. Content is organized logically from broad general information to highly specific engine, chassis, and electrical system modules. Detailed sections clarify the removal, installation, and assembly requirements for the 124.8 cc power plant. Meanwhile, the chassis chapters focus directly on steering geometry, brake systems, and final drive maintenance to keep bench work efficient. Prioritize shop safety when performing any maintenance; always verify torque values and stabilize the vehicle before beginning heavy teardown procedures to prevent injury or component failure.

Specification Highlights

Accurate factory data is critical for restoring original performance without relying on guesswork. Key technical benchmarks include a cylinder head bolt torque of 28–30 N-m (20–22 ft-lb) and intake and exhaust valve clearances set precisely at 0.08 mm. The baseline for cylinder compression is specified at 13.3 ± 1.0 kg/cm², and the fuel system capacity is rated at 7.5 liters.