The 450 EXC Racing, produced between 2000 and 2003, is a formidable off-road motorcycle renowned for its potent LC4 4-stroke engine and competition-focused design. Engineered for the demanding world of enduro and cross-country racing, this model embodies the "Ready to Race" philosophy, delivering exceptional performance, durability, and handling. Its powerful single-cylinder engine, approximately 450cc in displacement, coupled with long-travel suspension and a robust chassis, makes it a highly capable machine designed to excel in challenging terrains and competitive environments. This Service Repair Manual provides comprehensive guidance for the engine and its associated systems for the 450 EXC Racing (2000-2003). It covers essential maintenance procedures, detailed repair instructions for all major engine mechanical components, fuel, ignition, lubrication, cooling, and transmission systems, as well as troubleshooting common issues. The manual is an indispensable resource for owners, mechanics, and technicians aiming to maintain, service, and repair this high-performance off-road vehicle, ensuring its optimal operation and longevity. 🏷️ Basic Information Identification Make: KTM Model: 450 EXC Racing Model Variant: Engine Year: 2000-2003 Codes Engine Code General: LC4 (4-stroke) 👋 Introduction Market Position Market Position: The KTM 450 EXC Racing was a prominent model in the off-road and enduro competition segment during its production years, known for its performance-oriented engine and robust chassis. Competitive Analysis Competitors 2000-2003: Competed against models such as Honda CRF450X, Yamaha YZ450F (off-road variants), Husqvarna TE450, and Suzuki RM-Z450 (early models). Key Features Vehicle Key Vehicle Features: Powerful single-cylinder engine, long-travel suspension, durable chassis, designed for competitive off-road riding. Manual Purpose Manual Purpose: To provide comprehensive repair and maintenance guidance for the engine and related systems of the KTM 450 EXC Racing models from 2000 to 2003. 📋 Manual Details Coverage Areas Systems Covered: Engine Mechanical, Fuel System, Ignition System, Lubrication System, Cooling System, Transmission (Internal Components related to engine operation), Carburetion/Fuel Injection, Exhaust System, Electrical System (Engine Related). Page Count Estimated Page Count: 300-400 Manual Type Manual Type: Service Repair Manual Language Language: English Format Format: PDF 📖 Manual Coverage Systems Covered Engine Mechanical: Complete disassembly and assembly, piston, rings, cylinder, connecting rod, crankshaft, bearings, cylinder head, valves, camshafts, timing chain/belt, seals, gaskets. Fuel System: Carburetor (e.g., Keihin, Mikuni) tuning, cleaning, and rebuilding; fuel pump operation (if applicable); fuel lines, filters. Ignition System: CDI unit, ignition coil, spark plug specifications, timing adjustment, stator/rotor testing. Lubrication System: Oil pump operation, oil filter replacement, oil change intervals, oil capacity, troubleshooting oil pressure issues. Cooling System: Radiator, coolant hoses, water pump, thermostat operation, coolant specifications and flushing procedures. Transmission Internal: Gearbox inspection, clutch operation, clutch plate replacement, gear selection mechanism. Electrical Engine: Wiring diagrams related to engine components, starter motor, alternator/generator, sensor testing (e.g., crankshaft position sensor). Procedures Included Maintenance Procedures: Routine checks, oil and filter changes, spark plug replacement, air filter cleaning/replacement, valve clearance adjustment, coolant flush, chain adjustment. Repair Procedures: Complete engine teardown and rebuild, piston and cylinder replacement, crankshaft and connecting rod service, valve guide and seal replacement, bearing replacement, transmission gear replacement, clutch service. Troubleshooting: Diagnosis of common starting issues, running problems, overheating, oil leaks, strange noises, electrical faults affecting the engine. Technical Depth Technical Depth: Comprehensive; covers everything from basic maintenance to full engine overhaul, including torque specifications, clearances, and diagnostic charts. 📊 Manual Specifications File Format File Format: PDF (Portable Document Format) Print Quality Print Quality: High Resolution; designed for clear viewing and printing of diagrams and text. Binding Type Binding Type: N/A (Digital PDF format) Paper Type Paper Type: N/A (Digital PDF format) ⚙️ Engine Specifications Primary Engine Engine Type: 4-Stroke, Single Cylinder, Liquid-Cooled, DOHC Engine Displacement: Approximately 450cc (specific bore/stroke may vary slightly by year/variant). Engine Designation: LC4 Engine Platform Performance Horsepower Estimate: Approx. 50-55 HP (stock, may vary by tuning and specific model year). Torque Estimate: Approx. 40-45 Nm (stock, may vary). Fuel System Fuel Delivery: Carburetor (e.g., Keihin FCR or similar). Fuel Type: Unleaded Gasoline Lubrication System Oil Type Recommendation: High-quality synthetic motorcycle oil, SAE 10W-40 or 15W-50 (refer to manual for exact specification). Oil Capacity Engine Only: Approx. 1.1 - 1.3 Liters (check manual for exact figure). Cooling System Coolant Type: Ethylene Glycol based antifreeze coolant mixture (50/50). Timing Valve Actuation: Dual Overhead Camshafts (DOHC), Chain Driven. Ignition Ignition System Type: Digital CDI (Capacitor Discharge Ignition). 🔧 Transmission Standard Transmission Type: 5-Speed Manual Optional Optional Transmission: N/A Features Clutch Type: Wet Multi-Plate Clutch Transmission Oil Type: Engine Oil (shared sump, check manual for specific grade). Transmission Oil Capacity: Included in overall engine oil capacity, refer to manual. 📐 Dimensions Exterior Wheelbase: Varies by specific model year, typically around 1450-1480 mm. Weights Dry Weight Estimate: Approx. 110-115 kg (without fluids). Fuel Tank Capacity: Approx. 7-9 Liters. 🛡️ Safety Features Ratings Safety Ratings: N/A (Off-road competition vehicle, not typically subject to road vehicle safety ratings). Active Features Active Safety Features: Effective Braking System (Front/Rear...