1986-1991 Honda CR250R Service Manual (P/N 61351-KZ4-870)

• Official Honda publication P/N 61351-KZ4-870 detailing system maintenance and technical specifications across 309 pages.
• Covers 1986–1991 Honda CR250R motocross bikes equipped with liquid-cooled 2-stroke engines and Pro-Link rear suspension systems.
• Features 12 detailed wiring diagrams and electrical system schematics, 15 exploded-view engine/chassis diagrams, and 12 engine-specific torque data tables.
• High-resolution charts and visual assets preserved for accurate shop-floor reference.
• Documents the full production run evolution, from the 1986 base model through the post-1990 H.P.P. system updates.

Component and System Documentation

The 1986–1991 Honda CR250R service manual offers an in-depth breakdown of the mechanical systems behind this iconic motocross machine. Dedicated chapters focus on engine removal, cylinder head teardowns, piston assembly, and the intricacies of the H.P.P. (Honda Power Port) system. For the chassis, the text addresses front and rear suspension settings, hydraulic brake maintenance, and drivetrain configurations. Electrical system coverage includes ignition timing, CDI unit pinouts, and precise cable routing guidelines across all production years. Proper handling of these high-performance components requires professional care. Always observe standard shop safety protocols and relieve system pressures before beginning teardowns to prevent injury or equipment damage.

Specifications and Reference Data

Accurate technical data is critical for any bench rebuild or routine maintenance. This documentation provides exact engine clearances, maintenance schedules, system diagnostics, and torque settings for hundreds of fasteners. For instance, engine mounting bolt torque values are specified at 60–70 Nm for units manufactured after 1989. You will also find cylinder head nut torque specs listed at 24–29 Nm within the engine assembly section. Transmission oil capacity is detailed at 0.63 liters for the 1989 and later builds upon disassembly. Having these exact mechanical parameters on hand takes the guesswork out of professional-grade service work on the liquid-cooled two-stroke platform.