This manual covers the Yamaha DT50MX and DT80MX models from 1980, renowned lightweight dual-sport motorcycles popular for their robust two-stroke engines and accessible mechanics. These bikes were designed for both on-road and off-road use, offering a blend of trail capability and everyday usability. Yamaha's legacy in building durable and performance-oriented motorcycles, particularly in the two-stroke segment, is evident in these models. The DT series pioneered the dual-sport market, and the 'MX' designation signifies a more aggressive, off-road-focused variant known for its reliability and simple engineering, making it ideal for young riders and off-road enthusiasts.

The purpose of this Service & Repair Manual is to provide comprehensive guidance for the maintenance and repair of your Yamaha DT50MX or DT80MX. It details procedures for engine systems, including top-end and bottom-end overhauls, lubrication, cooling, ignition, and exhaust. The manual also covers transmission systems, fuel systems with carburetor tuning, electrical systems with wiring diagrams, chassis components, braking systems, and wheels and tires. Included are routine maintenance tasks, troubleshooting guides for common issues, detailed technical specifications, and safety guidelines. This manual is an essential resource for owners, mechanics, and technicians to ensure the continued performance and longevity of these iconic Yamaha motorcycles.