This manual provides comprehensive information for the 2003 KTM 640 LC4 DUKE II, a naked sportbike renowned for its potent single-cylinder LC4 engine and agile handling. Built with characteristic performance ethos, this model offers a raw and engaging riding experience, making it suitable for urban commuting, spirited rides, and even occasional light off-road excursions. Its lightweight chassis, combined with WP suspension components, contributes to its sharp responsiveness. The 640 LC4 DUKE II represents successful expansion into the street motorcycle market, building on the legacy of the versatile LC4 engine platform.

This English-language manual is designed to guide owners and technicians through the operation, maintenance, and basic troubleshooting of the 2003 KTM 640 LC4 DUKE II. It covers essential aspects including pre-ride inspections, routine maintenance procedures such as oil and filter changes, air filter care, and chain adjustments. The manual also details the engine, fuel, ignition, transmission, chassis, suspension, braking, wheel, and electrical systems, offering explanations of controls and instruments. While focusing on user-level maintenance and basic diagnostics, it provides the necessary knowledge to keep the motorcycle in optimal condition.