This workshop service repair manual covers YZ125 off-road motorcycles manufactured for the model years 2001, 2002, and 2003. The YZ125 is renowned for its powerful liquid-cooled, 124cc two-stroke engine, featuring the Power Valve System (YPVS) for optimized power delivery. Known for its agile handling, lightweight construction, and competitive performance in the 125cc motocross class, the YZ125 has a strong heritage in motorsports. This manual is designed for owners, mechanics, and enthusiasts seeking to maintain and repair this iconic off-road machine.

This comprehensive manual provides detailed, factory-authorized information essential for the upkeep and repair of your YZ125. It covers all major systems, including the engine, fuel system, transmission, suspension, brakes, and electrical system, offering step-by-step instructions for disassembly, assembly, inspection, and troubleshooting. You will find procedures for routine maintenance, component replacement, torque specifications, and the identification of specialized tools. With detailed diagrams and illustrations, this manual serves as an indispensable resource for ensuring the optimal performance and longevity of your 2001-2003 YZ125.