2000-2002 Yamaha WR400F(M) Factory Service Manual (P/N 5GS-28199-30, 1st Edition)

• Official Yamaha publication P/N 5GS-28199-30 (1st Edition, November 1999) covering 2000–2002 WR400F, WR400FM, and WR400F(M) racing models for US, European, Canadian, and Oceania markets
• 87 pages of factory reference material, including precise lubrication routing, cable charts, and comprehensive fastener torque tables
• Features the specialized tuning data required for suspension setup and chassis maintenance specific to the 5GS model-code build

Document Structure and Coverage

Knowing exactly where to find the right spec saves hours on the bench. This factory reference breaks down the WR400F into seven focused chapters. It starts with vehicle identification and control functions before diving into prep work for a teardown. From there, the middle sections provide the technical blueprint for both top-end and bottom-end engine work, along with chassis, steering, and suspension data. The final chapters deliver detailed electrical system diagrams and a dedicated tuning reference. Before applying force to any engine or suspension component, always cross-reference these factory torque specs and observe standard workshop safety practices to prevent component failure.

Specification Highlights

The WR400F utilizes a 399 cc, liquid-cooled, four-stroke DOHC powerplant. Getting the dry-sump lubrication system right is critical, and the contents include exact oil flow charts to verify correct line routing. You get hard numbers for engine tolerances. For instance, cylinder head warp limits are strictly capped at 0.05 mm. Intake valve clearances sit between 0.15 and 0.20 mm in the engine specification tables. Fuel delivery is handled by a KEIHIN FCR-MX39 carburetor feeding from a 12-liter tank. For routine fluid changes, the crankcase drain bolt torque is specified at a firm 20 Nm. This overview details the contents of the official OEM publication and serves as a reference for available technical data, rather than a step-by-step repair guide.