This manual covers the KTM 125 SX, 250 SX, 125 EXC, and 250 EXC models from the 2001 production year. These performance off-road motorcycles, part of the Second Generation SX/EXC Platform, are renowned for their potent 2-stroke engines, competitive chassis, and strong racing heritage. Built in Austria, KTM has a long-standing reputation for engineering quality and reliability in the off-road segment, with these models representing a significant evolution in their motocross and enduro offerings. They were designed to compete directly with other leading brands in their respective classes, known for their potent power delivery and agile handling.

The purpose of this factory service manual is to provide comprehensive technical information for the maintenance, repair, and overhaul of these KTM motorcycles. It details procedures for engine mechanical systems, including top-end and bottom-end rebuilds, transmission, clutch, ignition, and fuel systems. The manual also covers basic chassis and suspension repairs relevant to engine access, as well as engine-related electrical systems. With systematic troubleshooting charts, detailed specifications for tolerances and torques, and step-by-step disassembly and assembly instructions, this manual is an essential resource for owners, mechanics, and technicians seeking to maintain and repair their 2001 KTM 125/250 SX/EXC models with accuracy and completeness.