2003-2007 GAS GAS EC FSE 400/450 Service Manual

This official OEM publication from December 2002 details the production racer series for the 2003–2007 GAS GAS EC FSE 400 and EC FSE 450. It serves as the definitive reference for the 4-stroke, single-cylinder DOHC engine, providing exact baseline settings for shop work.

• Covers essential service and maintenance criteria for the long-stroke engine configuration and the Magneti Marelli injection system.
• Contains 21 detailed technical figures and component location diagrams.
• Features an extensive torque specification table for precise reassembly.

Engine and Chassis Documentation

The manual delivers precise technical data for the liquid-cooled, 4-cycle powerplant. It breaks down essential parameters for ignition system management and cooling system maintenance. Mechanics and DIY builders get the exact baseline settings needed for accurate diagnostics. The documentation also covers suspension tuning. It provides specific factory settings for both front fork and rear shock absorber rebound and compression damping.

Specification Highlights

This documentation outlines critical reference values required for daily workshop tasks. It specifies a 9 Nm (6 ft-lbs) torque for the water pump cover drain plug and 27 Nm (20 ft-lbs) for the spark plug. Transmission oil capacity requires 1800 cc of 5W50 API SF or SG fluid. Engine displacement is confirmed at either 399 cc or 449 cc, depending on the exact model variant. The coolant system capacity sits at 1.1 liters, and the steering stem head nut requires 44 Nm (4.5 kg-m) of torque.

Servicing competition-grade motorcycles involves significant mechanical risk and requires proper tooling. Always verify your equipment conditions and follow standard workshop safety protocols before applying these specifications.