The Kawasaki KFX400 is a performance-oriented All-Terrain Vehicle (ATV) designed for sport riding and off-road enthusiasts. Produced from 2003 to 2006, this model is recognized for its agile handling, powerful 398cc liquid-cooled engine, and robust construction, drawing on Kawasaki's extensive legacy in ATV manufacturing. Engineered with a strong steel frame and featuring a responsive 5-speed manual transmission with reverse, the KFX400 offers a dynamic riding experience. Its design prioritizes rider control and durability, making it a capable machine for various off-road terrains and a popular choice for those seeking a blend of performance and reliability in a sport ATV. This comprehensive service and repair manual provides detailed guidance for the maintenance and repair of the Kawasaki KFX400 ATV, covering model years 2003 through 2006. The manual encompasses all essential systems, including the engine, transmission, chassis, and electrical components, with step-by-step procedures for routine maintenance, troubleshooting, and complete overhauls. It features abundant diagrams and torque specifications to assist owners, mechanics, and technicians in understanding complex procedures and ensuring the longevity and optimal performance of their vehicle. The manual is presented in a high-resolution, searchable, and printable English format compatible with both Windows and MacOS.