This manual covers 400 EXC, 450 EXC, SMR, and SXS models manufactured between 2000 and 2007. These high-performance motorcycles, built around the robust LC4 engine architecture, are renowned for their powerful, torquey performance and exceptional off-road capability. Featuring premium WP suspension for superior damping and adjustability, along with agile chassis designs, these bikes are engineered for demanding terrain and competitive use. Whether for Enduro, Motocross, or Supermoto applications, motorcycles of this era are recognized for their racing heritage and handling prowess, with a strong emphasis on rider control and durability. This comprehensive Workshop Service Manual provides detailed information essential for the maintenance, repair, and troubleshooting of your motorcycle. It covers a wide array of systems, including engine mechanicals, fuel and ignition systems, transmission, drivetrain, suspension, brakes, and the electrical system. Within its pages, you will find procedures for routine maintenance, in-depth engine rebuilds, suspension and brake servicing, and electrical diagnostics. The manual also includes technical specifications, torque values, and troubleshooting charts, enabling owners and technicians to effectively maintain and restore these high-performance machines to optimal working condition. 🏷️ Basic Information Identification Make: KTM Model: 400 EXC, 450 EXC, SMR, SXS Year: 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Codes Common Chassis Codes: LC4 (general family), specific variations for EXC/SMR/SXS models 👋 Introduction Market Position Vehicle Segment: High-performance off-road motorcycles (Enduro, Motocross, Supermoto variants). Competitive Analysis Competitors: Yamaha YZ/WR, Honda CRF/XR, Suzuki RM/DR, Kawasaki KX/KLX, Husqvarna, GasGas. Key Features Engine Philosophy: Powerful, torquey LC4 single-cylinder engines known for their robustness and off-road capability. Suspension Performance: Premium WP suspension components providing exceptional damping and adjustability for demanding terrain. Handling: Agile and responsive chassis design optimized for competitive off-road riding. 📋 Manual Details Coverage Areas Manual Type: Workshop Service Manual / Repair Manual Language: English Format: PDF Download Page Count Estimated Page Count: Varies by specific model variant and year; typically 300-600 pages for comprehensive coverage. 📖 Manual Coverage Systems Covered Engine Mechanical: Disassembly, assembly, inspection, repair of cylinder head, valves, piston, crankshaft, connecting rod, oil pump, and cooling system. Fuel System: Carburetor (Keihin, Mikuni variants), fuel pump, fuel tank, lines, and filtration. Ignition System: CDI unit, ignition coil, spark plug, stator, and wiring. Transmission Drivetrain: Gearbox disassembly, inspection, repair, clutch operation, chain and sprocket maintenance. Suspension Front: Fork disassembly, seal replacement, oil levels, spring rates, damping adjustments (WP USD forks common). Suspension Rear: Monoshock (WP PDS or linkage systems), shock absorber service, linkage bearing maintenance. Brakes Front: Brake caliper service, master cylinder overhaul, pad replacement, disc inspection, hydraulic lines. Brakes Rear: Brake caliper service, master cylinder overhaul, pad replacement, disc inspection, hydraulic lines. Electrical System: Wiring diagrams, lighting, starter motor, battery maintenance, charging system, fuse box, switchgear. Frame Chassis: Frame inspection, steering head bearing service, swingarm maintenance, subframe. Bodywork: Fairing removal and installation, seat, fuel tank mounting, fenders. Procedures Included Routine Maintenance: Oil changes, filter replacements, chain lubrication and adjustment, air filter cleaning/replacement, spark plug checks, valve clearance checks. Troubleshooting: Diagnostic tables for common starting, running, and electrical issues. Engine Rebuild: Complete engine disassembly, component inspection, torque specifications for critical fasteners, reassembly procedures. Suspension Service: Front fork seal replacement, rear shock absorber service (where applicable), linkage lubrication. Brake Service: Brake bleeding, caliper piston cleaning and lubrication, pad and disc replacement. Electrical Diagnostics: Using multimeters to test circuits, identifying faulty components based on symptoms. Carburetor Tuning: Adjustment of idle speed, mixture screws, jetting recommendations for altitude and conditions. Technical Depth Diagnostics Level: Advanced diagnostics including troubleshooting charts and component testing procedures. Repair Scope: Comprehensive repair procedures for major mechanical and electrical components. Rebuild Procedures: Detailed instructions for engine and transmission rebuilds. Technical Drawings: Includes exploded diagrams and illustrations of components and assemblies. 📊 Manual Specifications File Format File Format: PDF Searchable Text: Typically yes, allowing for easy keyword searches. Print Quality Print Quality: High-resolution scans suitable for printing. Binding Type Binding Type: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type: Four-stroke, single-cylinder, liquid-cooled (LC4 architecture). Displacement 400: Approximately 398cc. Displacement 450: Approximately 449cc (exact figures may vary slightly by year and sub-model). Bore X Stroke 400: Typical around 95mm x 70.5mm (check specific model year). Bore X Stroke 450: Typical around 97mm x 60.8mm (check specific model year). Performance Horsepower 400: Estimated 45-55 HP (may vary with tuning and exhaust). Horsepower 450: Estimated 50-60 HP (may vary with tuning and exhaust). Torque: Strong mid-range torque characteristic of LC4 engines. Fuel System Carburetor Type: Keihin FCR flat-slide or Mikuni VM (depending on year and model variant). Fuel Type: Unleaded Gasoline, 91 octane or higher recommended. Engine Features Valve Train: SOHC, 4 valves per cylinder. Starting System: Electric Starter (standard on most variants). Cooling System: Liquid-cooled. 🔧 Transmission Standard Transmission Type: 6-speed constant mesh manual gearbox. Clutch Type: Wet multi-plate clutch, hydraulically operated. Features Gear...