The Husqvarna SM 400 and SM 450 R models, produced between 2001 and 2004, represent a blend of off-road heritage and on-road performance, positioning them in the supermoto segment. These motorcycles are known for their robust single-cylinder, liquid-cooled engines, offering impressive power for their class, with the SM 400 typically around 40-45 HP and the SM 450 R around 45-50 HP. Engineered with a focus on agility and responsiveness, they feature a 5-speed constant mesh transmission and wet multi-plate clutch, making them adept for both spirited riding and general use. The manufacturer's legacy contributes to the perceived reliability and performance capabilities of these models, which were part of a significant era for the brand. This comprehensive Service Repair Workshop Manual provides extensive A-Z coverage for all repairs pertaining to the Husqvarna SM 400 and SM 450 R models from 2001-2004. It is meticulously designed to assist owners and professional mechanics alike, offering detailed procedures for engine and clutch service, transmission overhauls, cooling, fuel, and exhaust systems, as well as ignition and electrical components. The manual also covers brake systems, wheels, tires, steering, suspension, and frame/bodywork, complete with wiring diagrams and fault-finding troubleshooting guides. With high-quality illustrations and professional-grade information, this English-language manual ensures thorough understanding and effective maintenance and repair for these motorcycles.