This manual covers the 450 SX-F, 525 SX, and 450 SXS-F models from the Second Generation SX/SX-F series, produced between 2007 and 2009. These competition motocross and supercross motorcycles embody the 'Ready to Race' ethos, offering a lightweight, powerful, and agile design. Engineered for high-performance off-road racing, these machines have a strong heritage of championship wins and are renowned for their potent engine performance and advanced suspension systems. This comprehensive Factory Service Repair Workshop Manual is designed to provide essential, in-depth technical knowledge for the maintenance, repair, and optimal performance tuning of your competition motorcycle. It offers detailed coverage of engine service, repair, and troubleshooting, alongside general maintenance procedures and diagnostics. Key areas include complete engine disassembly and assembly, fuel system servicing, ignition and cooling system maintenance, lubrication, exhaust, clutch, and transmission internal procedures, as well as electrical system checks. With over 300 pages of information, this manual is an invaluable resource for enthusiasts, privateer racers, professional mechanics, and dealerships seeking to maintain these specialized racing machines. 🏷️ Basic Information Identification Make: KTM Model: 450 SX-F / 525 SX / 450 SXS-F Model Variant: Competition Motocross / Supercross Generation Generation Name: Second Generation SX/SX-F Codes Chassis Codes: 450 SX-F (2007-2009), 525 SX (2007-2009), 450 SXS-F (2007-2009) 👋 Introduction Market Position Segment: High-performance Motocross/Supercross Off-Road Motorcycles Target Audience: Enthusiasts, Privateer Racers, Professional Mechanics, KTM Dealerships Competitive Analysis Key Competitors: Yamaha YZ450F, Honda CRF450R, Suzuki RM-Z450, Kawasaki KX450F Key Features Vehicle Philosophy: Lightweight, powerful, agile, and race-oriented design, embodying KTM's 'Ready to Race' ethos. Manual Value Proposition: Provides essential, in-depth technical knowledge for optimal maintenance, repair, and performance tuning of these specialized racing machines. 📋 Manual Details Coverage Areas Primary Focus: Engine Service, Repair, and Troubleshooting Secondary Focus: General Maintenance, Diagnostics Page Count Estimated Pages: 300+ Manual Type Type: Factory Service Repair Workshop Manual Language Language: English Format Format: Downloadable PDF 📖 Manual Coverage Systems Covered Engine Mechanical: Complete engine disassembly, assembly, inspection, and repair for all covered models. Fuel System: Carburetor (Mikuni VM40 for 525 SX, Keihin FCR for 450 SX-F/SXS-F) tuning, cleaning, and repair. Fuel injection system details (if applicable to specific sub-models within the range). Ignition System: Ignition timing, component testing (coil, CDI), troubleshooting. Cooling System: Radiator, coolant, water pump, thermostat inspection and service. Lubrication System: Oil pump, oil filter, oil passages, oil change procedures and specifications. Exhaust System: Exhaust pipe and muffler maintenance, inspection for damage. Clutch System: Clutch operation, disassembly, inspection, replacement of plates and springs. Transmission Internal: Gearbox disassembly, inspection of gears, shafts, and shift mechanisms. Electrical System: Basic electrical checks, wiring diagrams (if included), starter motor, stator. Procedures Included Routine Maintenance: Oil changes, filter replacements, chain adjustment, air filter cleaning, spark plug service. Engine Rebuild: Top-end rebuild (piston, rings, valves), bottom-end rebuild (crankshaft, connecting rod, bearings). Troubleshooting: Diagnostic flowcharts, common problems and their solutions. Component Replacement: Detailed steps for replacing wear items and major components. Torque Specifications: Crucial torque values for all critical fasteners and engine components. Special Tools: Identification of required special tools for specific procedures. Technical Depth Depth Level: Comprehensive Factory Level - Suitable for professional mechanics and advanced DIY enthusiasts. Diagnostic Capability: Advanced diagnostic procedures for engine performance and electrical issues. Rebuild Instructions: Detailed step-by-step instructions for complete engine disassembly and reassembly. 📊 Manual Specifications File Format Format Details: PDF (Portable Document Format), optimized for digital viewing and printing. Searchability: Text-searchable PDF for quick information retrieval. Print Quality Quality Description: High-resolution scans of original factory documentation, ensuring clarity of text and diagrams. Binding Type Binding: Not Applicable (Digital Download) Paper Type Paper: Not Applicable (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type 450: 4-stroke, single-cylinder, SOHC, 4 valves per cylinder Engine Type 525: 4-stroke, single-cylinder, SOHC, 4 valves per cylinder Bore X Stroke 450: 97 x 60.8 mm (approx.) Bore X Stroke 525: 97 x 69.2 mm (approx.) Displacement 450: 449.3 cc Displacement 525: 510.4 cc Compression Ratio Approx: 12.5:1 to 13.5:1 (model dependent) Performance Horsepower 450 Approx: 50-55 HP (at crankshaft) Horsepower 525 Approx: 55-60 HP (at crankshaft) Torque Approx: 45-50 Nm (model dependent) Fuel System Carburetor 450 Sx-F Sxs-F: Keihin FCR 41 (Flat CR carburetor) Carburetor 525 Sx: Mikuni VM40 Fuel Type: Unleaded gasoline, minimum 95 RON 🔧 Transmission Standard Transmission Type: Constant mesh, 5-speed sequential Optional Optional Transmissions: N/A (Race-spec bikes typically have a single, fixed transmission) Features Clutch Type: Hydraulically operated, multi-disc wet clutch (Brembo hydraulic system) Gear Ratios: Specific ratios are detailed within the manual, tailored for motocross racing. 📐 Dimensions Exterior Frame Type: CrMo Steel Central Double-Cradle Frame Wheelbase Approx: 1480 mm Ground Clearance Approx: 355 mm Weights Dry Weight 450 Approx: 107 kg Dry Weight 525 Approx: 108 kg 🛡️ Safety Features Ratings Safety Ratings: N/A (Competition motorcycles are not subject to typical road vehicle safety standards and testing). Active Features Braking System Front:...