This manual covers the Yamaha YZ125, a performance-oriented motocross motorcycle renowned for its powerful two-stroke engine and agile handling. Yamaha has a significant legacy in motocross, with the YZ series consistently evolving to deliver competitive performance. This parts catalogue, specifically for the YZ125-P model variant 5NY1-2-3-4, provides comprehensive part number listings and detailed visual diagrams essential for maintaining and repairing this iconic machine. It is designed for owners, independent repair shops, and DIY enthusiasts seeking accurate part identification and procurement, enabling cost-effective maintenance.

The purpose of this manual is to serve as an indispensable resource for all aspects of Yamaha YZ125 parts identification and ordering. It details components across all major systems, including the engine, fuel and air system, braking, electrical, chassis, and more, offering a granular breakdown of assemblies with clear, exploded-view diagrams. This level of detail ensures correct assembly and disassembly, facilitating the acquisition of necessary parts to keep the motorcycle in optimal condition. It is structured to be a primary reference tool, mirroring the information used by professional garages, thereby empowering users to perform accurate repairs and maintenance efficiently.