1998-2000 Yamaha WR400F(K) Owner's Service Manual

Inside the 1998–2000 Yamaha WR400F(K) Service Documentation

• Covers 1998–2000 Yamaha WR400F(K) high-performance off-road motorcycles, including specific model code 5BF-28199-80 configurations
• Official OEM publication P/N 5BF-28199-80, first edition dated December 1997
• Includes 12 detailed torque specification tables and 15 exploded-view component diagrams for engine and chassis systems
• Downloads to your account within seconds of checkout
• Page spreads stay legible when printed at original size
• OCR text layer lets you jump to a torque spec by keyword
• This first edition serves as the foundational reference for the WR400F(K) series, providing critical factory-setting data and assembly tolerances for the 400 cc liquid-cooled power unit

Factory-Authorized Technical Scope

The 1998–2000 Yamaha WR400F(K) service manual covers mechanical operation, routine inspection, and system-level adjustment protocols. Seven core chapters organize technical data spanning the engine top end, transmission, chassis geometry, and electrical systems. Detailed maintenance schedules define service intervals for the dry-sump lubrication system and cooling components. Procedures for the KEIHIN FCR 39H carburetor and ignition systems provide the reference framework necessary for tuning the WR400F(K) engine for competitive closed-course environments.

Specification and Reference Highlights

Engine internal tolerances, including valve clearance specs of 0.15–0.20 mm (intake) and 0.25–0.30 mm (exhaust), are documented in the maintenance tables. Primary transmission reduction is specified at 62/21 (2.952) within the drive system section. Cylinder head stud bolt torque is established at 7 Nm for M6x1.0 threads in the assembly data. Standard cooling system capacity for the 1998–2000 Yamaha WR400F(K) is documented at 1.15 liters. For those requiring what an OEM service publication covers, this volume details component wear limits such as the 0.03 mm cam-chain runout limit.

Reference only — always consult a certified technician before performing service on this equipment. This official 578-page Yamaha OEM service manual covers the 1998–2000 Yamaha WR400F(K) motorcycle, documenting engine, chassis, electrical, and fuel-system specifications for the 5BF-series build.