This manual covers the KTM 125 SX, 200 SX, 125 EXC, and 200 EXC models, produced from 2003 onward. These performance-oriented off-road motorcycles are renowned for their racing heritage and are designed for motocross and enduro competition. Featuring liquid-cooled, two-stroke engines with capacities of 125cc and 200cc, they are equipped with advanced systems such as KTM PowerJet or similar power valve controls and often V-Force reed block induction. The chassis typically utilizes a chromium-molybdenum steel frame, WP USD front forks, and a WP Monoshock PDS rear suspension, contributing to their agile handling and off-road capability.

This comprehensive service repair manual provides in-depth guidance for engine service, repair, and overhaul, covering all essential mechanical components, fuel delivery, ignition, and exhaust systems. It details routine maintenance procedures, engine rebuilds, and troubleshooting common issues. The manual is an indispensable resource for KTM owners, mechanics, and technicians, offering detailed procedures, schematics, and specifications necessary for maintaining and repairing these high-performance machines. Its scope ensures that users can perform everything from basic service intervals to complete engine teardown and diagnostics.