The Yamaha WR426F, produced from 2000 to 2008, represents a robust and capable off-road motorcycle, built upon Yamaha's extensive heritage in competitive two-wheeled performance. Known for its powerful engine and adept handling, this model has been a favored choice for riders engaged in various off-road disciplines. Its design emphasizes reliability and performance, making it a strong contender in its class and a respected machine within the off-road community. This Factory Service Repair Manual provides comprehensive English-language guidance for the Yamaha WR426F, covering all model years from 2000 through 2008. It details a wide array of maintenance and repair procedures, including general information, fuel system, cooling system, engine top-end, clutch, lubrication system, engine removal and installation, crankshaft and transmission, wheels and tires, final drive, brakes, suspension, steering, frame, and electrical systems. The manual also includes detailed engine management, wiring diagrams, electrical troubleshooting, and specific guidance on diagnostics, tuning, and part testing, empowering owners and technicians to maintain and repair the vehicle with factory-level accuracy.