The Yamaha YZ250B, produced in 1991, is a formidable motocross motorcycle renowned for its powerful liquid-cooled, 2-stroke engine featuring the Yamaha Power Valve System (YPVS). This first-generation model, part of the esteemed YZ250 lineage, was engineered for aggressive riding and competition, offering a potent blend of power delivery and agility. Its long-travel front forks and Monoshock rear suspension are designed to excel in demanding off-road conditions, making it a competitive choice against contemporaries like the Honda CR250R and Kawasaki KX250. The YZ250B's robust construction and performance-focused design underscore Yamaha's commitment to motorsport excellence.
This comprehensive service manual provides essential information for the maintenance, repair, and troubleshooting of your 1991 Yamaha YZ250B. It covers all critical systems, including the engine's top and bottom end, transmission, fuel and ignition systems, exhaust, suspension, brakes, wheels, and electrical components. Detailed procedures for disassembly, assembly, routine maintenance, and component rebuilds are included, along with diagnostic charts for common issues and specific technical data. This manual is an indispensable resource for owners, mechanics, and technicians aiming to preserve the performance and reliability of this iconic motocross machine.
