This manual covers the 125 SX, 200 SX, 125 MXC, 200 MXC, 125 EXC, and 200 EXC models from the 2003 model year. These are high-performance, liquid-cooled, two-stroke off-road motorcycles known for their powerful engines and agile handling. The SX variants are designed for motocross racing, while the EXC and MXC models are built for enduro and cross-country riding, respectively, often featuring additional equipment for trail use. Austrian heritage in motorcycle manufacturing is evident in the robust engineering and competitive spirit embodied by these machines, which have a strong lineage in motorsport. This comprehensive service repair manual provides detailed instructions and technical specifications essential for the maintenance, diagnosis, and repair of your motorcycle. It covers all major systems, including engine mechanicals, electrical components, fuel system, cooling, transmission, suspension, brakes, wheels, tires, and chassis. The manual offers step-by-step procedures for routine maintenance, troubleshooting common issues, and complete rebuilds, ensuring that owners and technicians can effectively keep these off-road machines in optimal condition. With over 300 pages of information, this English-language guide is an invaluable resource for preserving the performance and longevity of your 2003 model. 🏷️ Basic Information Identification Make: KTM Model: 125 SX, 200 SX, 125 MXC, 200 MXC, 125 EXC, 200 EXC Year: 2003 Codes Engine Code 125: LC2 125 Engine Code 200: LC2 200 👋 Introduction Market Position Segment: Off-road motorcycles (Motocross, Enduro, Cross-Country). Target Audience: KTM owners performing DIY maintenance, repairs, and rebuilds. Competitive Analysis Competitors 2003: Yamaha YZ125/250, Suzuki RM125, Honda CR125R, Kawasaki KX125; Husqvarna, Beta. Key Features Manual Value Proposition: Provides in-depth technical knowledge crucial for maintaining and repairing high-performance KTM off-road machines. Kew Selling Points: Covers multiple popular models and variants within the 125cc and 200cc displacement range for the specific year. 📋 Manual Details Coverage Areas Models Covered: KTM 125 SX, 200 SX, 125 MXC, 200 MXC, 125 EXC, 200 EXC Model Years: 2003 Page Count Estimated Pages: 300+ Manual Type Type: Full Service Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Mechanical: Complete engine overhaul, rebuild procedures, piston, cylinder, crankshaft, connecting rod, valve timing, lubrication system. Engine Electrical: Ignition system, CDI unit, spark plug, stator, wiring diagrams, troubleshooting electrical faults. Fuel System: Carburetor tuning and rebuilding (Mikuni VM series), fuel tank, fuel lines, fuel filter replacement. Cooling System: Radiator, coolant, water pump, hoses, thermostat (if applicable). Transmission: Gearbox disassembly and assembly, clutch operation and replacement, shift mechanism, gearbox oil specifications and change intervals. Suspension Front: Front fork disassembly, service, seal replacement, oil level and type, spring rates, damping adjustments. Brakes Front: Brake caliper service, master cylinder overhaul, brake pad replacement, fluid type and bleeding procedure, rotor specifications. Wheels Tires: Wheel bearing maintenance, spoke tensioning, tire pressure recommendations, tire size specifications. Frame Chassis: Frame inspection, steering head bearing service, swingarm maintenance. Exhaust System: Exhaust pipe and silencer maintenance, checking for leaks. Suspension Rear Suspension Rear: Rear shock absorber service, linkage maintenance, spring preload adjustment. Brakes Rear Brakes Rear: Rear brake system service, caliper, master cylinder, pad replacement, fluid type, bleeding. Procedures Included Maintenance: Routine checks, lubrication points, air filter cleaning/replacement, spark plug replacement, chain adjustment and lubrication. Troubleshooting: Diagnostic flowcharts for common problems, electrical fault finding, engine performance issues. Repair: Step-by-step instructions for component replacement and repair across all major systems. Rebuild: Detailed procedures for complete engine and gearbox rebuilds. Installation: Instructions for installing common aftermarket parts or performing specific upgrades. Technical Depth Depth: Comprehensive, covering everything from basic maintenance to full engine and gearbox rebuilds. 📊 Manual Specifications File Format File Type: PDF Searchable: Yes (typically for PDF manuals) Print Quality Printability: Printable (standard PDF feature) Binding Type Binding: N/A (Digital PDF) Paper Type Paper Quality: N/A (Digital PDF) ⚙️ Engine Specifications Primary Engine Type 125: Single-cylinder, 2-stroke, liquid-cooled (LC2). Bore X Stroke 125: 54.0 mm x 54.5 mm (typical). Displacement 125: 124.8 cc Type 200: Single-cylinder, 2-stroke, liquid-cooled (LC2). Bore X Stroke 200: 62.5 mm x 65.0 mm (typical). Displacement 200: 197.5 cc Performance Horsepower 125 Est: ~30-35 HP Horsepower 200 Est: ~40-45 HP Fuel System Carburetor Model: Mikuni VM28SS (common for 125/200 SX models, other variants may use different specs). Fuel Type: Unleaded gasoline (minimum 91 octane recommended), mixed with 2-stroke oil. Premix Ratio: Typically 40:1 or 50:1 (refer to manual for exact specification). Lubrication Oil Type Premix: High-quality 2-stroke motorcycle oil. 🔧 Transmission Standard Type: 6-speed constant mesh manual transmission. Features Clutch Type: Wet multi-plate clutch. Gearbox Oil Type: SAE 10W-40 motorcycle gear oil (refer to manual for exact specification). Gearbox Oil Capacity: Approx. 0.65 Liters (refer to manual for exact specification). 📐 Dimensions Exterior Frame Type: Chromium-molybdenum steel trellis frame. Weights Dry Weight 125 Approx: 90-95 kg Dry Weight 200 Approx: 95-100 kg Fuel Capacity: 7.5 - 9.0 Liters (varies by model variant). 🛡️ Safety Features Ratings Crash Test Ratings: N/A...