Model:
450 SX-F / 525 SX / 450 SXS-F
Model Variant:
Competition Motocross / Supercross
Generation Name:
Second Generation SX/SX-F
Chassis Codes:
450 SX-F (2007-2009), 525 SX (2007-2009), 450 SXS-F (2007-2009)
Segment:
High-performance Motocross/Supercross Off-Road Motorcycles
Target Audience:
Enthusiasts, Privateer Racers, Professional Mechanics, KTM Dealerships
Key Competitors:
Yamaha YZ450F, Honda CRF450R, Suzuki RM-Z450, Kawasaki KX450F
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.
Primary Focus:
Engine Service, Repair, and Troubleshooting
Secondary Focus:
General Maintenance, Diagnostics
Type:
Factory Service Repair Workshop Manual
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.
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.
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.
Format Details:
PDF (Portable Document Format), optimized for digital viewing and printing.
Searchability:
Text-searchable PDF for quick information retrieval.
Quality Description:
High-resolution scans of original factory documentation, ensuring clarity of text and diagrams.
Binding:
Not Applicable (Digital Download)
Paper:
Not Applicable (Digital Download)
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)
Horsepower 450 Approx:
50-55 HP (at crankshaft)
Horsepower 525 Approx:
55-60 HP (at crankshaft)
Torque Approx:
45-50 Nm (model dependent)
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 Type:
Constant mesh, 5-speed sequential
Optional Transmissions:
N/A (Race-spec bikes typically have a single, fixed transmission)
Clutch Type:
Hydraulically operated, multi-disc wet clutch (Brembo hydraulic system)
Gear Ratios:
Specific ratios are detailed within the manual, tailored for motocross racing.
Safety Ratings:
N/A (Competition motorcycles are not subject to typical road vehicle safety standards and testing).
Braking System Front:
Hydraulic disc brake, Brembo caliper, 260mm disc
Braking System Rear:
Hydraulic disc brake, Brembo caliper, 220mm disc
Suspension Front:
WP USD (Upside-Down) forks, adjustable compression and rebound damping. Specific model details (e.g., 50mm Extreme M) are in the manual.
Suspension Rear:
WP Monoshock with adjustable preload, compression, and rebound damping.
Infotainment System:
N/A (Purely performance-focused racing machine, no infotainment features).
Driver Assistance:
N/A (No electronic rider aids like traction control or ABS on these models).
Connectivity Features:
N/A (No Bluetooth, Wi-Fi, or smartphone integration).
Oil Change Engine:
Every 15-25 operating hours or after significant race events (refer to manual for precise recommendations).
Air Filter Cleaning:
After every ride or as needed depending on conditions.
Valve Clearance Check:
Every 30-50 operating hours.
Engine Oil Type:
High-quality 4-stroke motorcycle oil, JASO MA/MA2 certified, SAE 10W-40 or 10W-50 recommended (specific viscosity depends on operating temperature, refer to manual).
Clutch Fluid Type:
Brake fluid DOT 4 or DOT 5.1 (for Brembo hydraulic clutch).
Coolant Type:
Ethylene glycol-based coolant with anti-corrosion additives, mixed 50/50 with distilled water.
Engine Wear:
Piston, rings, and valve wear can occur with high hours; regular inspection is crucial. Potential for cam chain tensioner wear.
Clutch Slippage:
Can occur with aggressive use or if oil is contaminated; proper maintenance is key.
Carburetor Tuning:
May require adjustment for altitude or temperature changes.
Ktm Focus:
KTM has a long-standing heritage in off-road racing, particularly in motocross, enduro, and rally raid, known for producing powerful, purpose-built machines.
Sx Series Development:
The SX and SX-F series represent KTM's flagship motocross offerings, evolving significantly year-on-year with advancements in engine technology, chassis design, and suspension.
Manufacturing Location:
Austria (KTM AG)
Racing Success:
KTM SX/SX-F models have a strong history of winning championships and races across various national and international motocross and supercross events.
Motorcycle Press Reviews:
Consistently rated highly by motorcycle publications for power delivery, suspension performance, and handling.
Homologation:
Not road-legal; designed exclusively for closed-course competition.
