The 2004 Firebolt XB9R and XB12R represent a distinctive era in American sportbike engineering, known for their performance-oriented design and V-Twin power. These motorcycles, originating from an innovative approach, feature a unique chassis design that integrates the fuel tank and emphasizes mass centralization for superior handling. With their derived V-Twin engines, offering displacements of 984cc for the XB9R and 1203cc for the XB12R, these models deliver robust torque and spirited performance. The Firebolt's sportbike segment positioning and its philosophy of cutting-edge engineering have made it a notable machine for enthusiasts seeking a blend of power and agile dynamics. This comprehensive workshop manual serves as an essential resource for the maintenance, repair, and understanding of the 2004 Firebolt XB9R and XB12R. It covers a wide array of systems, including detailed procedures for the engine, transmission, drivetrain, chassis, suspension, and electrical systems. Owners and technicians will find guidance on routine maintenance, major repairs, advanced troubleshooting, and diagnostics. The manual's format ensures accessibility and ease of use, providing the necessary technical specifications and procedural information to keep these performance motorcycles in optimal condition.