This manual provides comprehensive service and repair information for the KTM 400 LC4 engine, covering production years from 1998 through 2005. The LC4 engine is renowned for its robust torque and rugged performance, making it a staple in KTM's high-performance single-cylinder off-road and supermoto motorcycles. Its design emphasizes strong low-to-mid-range power delivery, ideal for demanding riding conditions.

This service repair manual is designed to assist owners, mechanics, and technicians in maintaining and repairing the KTM 400 LC4 engine. It details essential procedures including routine maintenance, engine assembly and disassembly, lubrication and cooling systems, fuel and ignition systems, valve train adjustments, and troubleshooting common issues. With precise torque specifications and component testing guidance, this manual ensures the longevity and optimal performance of your LC4 engine.