Category:
High-Performance Motocross/Supercross Competition Bike
Target Audience:
Professional motocross racers, serious amateur competitors, and dedicated off-road enthusiasts
Key Competitors 2011:
Yamaha YZ450F, Honda CRF450R, Kawasaki KX450F, Suzuki RM-Z450
Engine Architecture:
Single-cylinder, 4-stroke, DOHC, liquid-cooled
Chassis Design:
Lightweight, high-strength chrome-molybdenum steel frame
Suspension:
Advanced WP suspension components (USD front forks, Monoshock rear)
Performance Focus:
Emphasis on power delivery, handling agility, and race-proven components
Primary Coverage:
Engine Service and Repair
Secondary Coverage:
Maintenance, Troubleshooting, Diagnostics
Estimated Pages:
300-400 (typical for comprehensive engine manuals)
Type:
Official Factory Service Manual / Repair Manual
Language:
English (standard for most KTM service manuals)
Format:
Digital (PDF) - Optimized for Searchability and Printing
Engine Mechanical:
Complete disassembly, inspection, reassembly of all internal engine components (pistons, rings, connecting rods, crankshaft, valves, camshafts, timing chain, etc.)
Engine Lubrication:
Oil pump, oil filter, oil passages, oil cooler (if applicable), lubrication system troubleshooting
Cooling System:
Radiator, water pump, coolant passages, thermostat, coolant bleeding procedures
Fuel System:
Fuel injection system (throttle body, injectors, fuel pump, pressure regulator), fuel filter replacement
Ignition System:
Ignition coil, spark plug, CDI unit, timing sensor diagnosis
Exhaust System:
Muffler, header pipe, O2 sensor (if applicable) inspection and replacement
Scheduled Maintenance:
Oil and filter changes, air filter cleaning/replacement, spark plug inspection/replacement, valve clearance checks and adjustment
Troubleshooting Diagnostics:
Step-by-step diagnostic procedures for common engine problems, error code interpretation (if applicable)
Repair Rebuild:
Detailed instructions for component replacement and complete engine rebuilds
Torque Specifications:
Precise torque values for all critical fasteners
Special Tool Requirements:
Identification of any specialized tools needed for specific procedures
Level Of Detail:
Comprehensive - suitable for professional mechanics and experienced DIY enthusiasts
Diagnostic Capabilities:
Advanced diagnostics for engine performance issues, fuel delivery, and ignition timing
Rebuild Procedures:
Full engine rebuild instructions, including tolerances and clearances
Displacement 450:
Approx. 449.3 cc
Bore X Stroke 450:
Likely around 97 mm x 60.8 mm (typical for this era's 450cc)
Compression Ratio 450:
Typically around 12.0:1 to 12.5:1
Valvetrain:
DOHC, 4 valves per cylinder
Cooling Method:
Liquid-cooled
Engine Type:
Single-cylinder, 4-stroke
Oil Capacity Engine:
Approximately 0.7 - 0.8 Liters (engine oil only, dry fill)
Oil Capacity Total:
Approximately 1.0 - 1.1 Liters (including transmission/clutch sump)
Recommended Oil Viscosity:
SAE 10W-40 (typically JASO MA certified for wet clutch)
Oil Filter Part Number:
KTM Part Number 77038005000 (or equivalent aftermarket)
Horsepower Estimated 450:
Approx. 50-55 HP (at crank)
Torque Estimated 450:
Approx. 45-48 Nm (at crank)
Fuel Delivery:
Electronic Fuel Injection (EFI) - Keihin or Mikuni throttle body
Fuel Type:
Unleaded Gasoline, minimum 95 RON (Octane Rating)
Throttle Body Size:
Likely 42mm or 44mm
Displacement 505:
Approx. 505 cc
Bore X Stroke 505:
Likely a larger bore or longer stroke compared to the 450, e.g., 97 mm x 67.7 mm (typical for 505cc applications)
Horsepower Estimated 505:
Approx. 53-58 HP (at crank, increased torque)
Type:
Constant-mesh, 4-speed (common for SX-F models)
Clutch:
Wet multi-disc clutch, hydraulically operated (Sachs or Magura system)
Transmission Oil Type:
SAE 10W-40 or 10W-50, JASO MA certified motorcycle oil
Transmission Oil Capacity:
Approx. 0.3 - 0.4 Liters
Frame Type:
Central double-cradle, 25CrMo4 steel
Wheelbase:
Approx. 1470 mm ± 10 mm (57.9″ ± 0.4″)
Ground Clearance:
Approx. 350 mm (13.8″)
Dry Weight:
Approx. 105 kg (231.5 lbs)
Fuel Tank Capacity:
Approx. 7.0 Liters (1.85 US gal)
Seat Height:
Approx. 950 mm (37.4″)
Crash Safety Rating:
N/A (Off-road competition vehicles are not subject to road vehicle safety regulations)
Braking System Front:
Brembo 2-piston caliper with 260 mm wave disc
Braking System Rear:
Brembo 1-piston caliper with 220 mm wave disc
Handlebar Protection:
Integrated handlebar padding and handguards
Infotainment System:
N/A (Competition motocross bike, no infotainment features)
Traction Control:
N/A (Standard on 2011 models)
Launch Control:
N/A (Standard on 2011 models)
Bluetooth Connectivity:
N/A (Standard on 2011 models)
Engine Oil Change:
Every 10-15 hours of riding, or as recommended by KTM for specific racing conditions.
Air Filter Cleaning:
After every few rides, or more frequently in dusty conditions.
Valve Clearance Check:
Every 20-30 hours of riding, or as specified in the manual.
Spark Plug Inspection:
Every 10-15 hours of riding.
Coolant:
Mixture of distilled water and a high-quality antifreeze coolant (typically ethylene glycol-based) with corrosion inhibitors. Refer to manual for specific brand/type recommendations.
Brake Fluid:
DOT 4 hydraulic brake fluid
Common Wear Items:
Piston and rings, valve guides and seals, clutch plates, wheel bearings, linkage bearings, swingarm bearings.
Potential Failures:
Overheating due to coolant leaks or insufficient airflow, excessive engine wear from prolonged use without proper maintenance, clutch slip under heavy load.
Brand Focus:
KTM is renowned for its dominance in off-road motorsports, particularly motocross and rally racing.
Sx-F Lineage:
The SX-F line represents KTM's flagship 4-stroke motocross platform, continuously developed with race-winning technology.
2011 Model Updates:
The 2011 models saw updates including revised engine mapping, improved suspension settings, and chassis refinements based on racing feedback.
Manufacturing Location:
Mattighofen, Austria
Motocross Magazine Awards:
KTM SX-F models consistently receive high praise and 'bike of the year' awards from leading motocross publications for their performance and handling.
Performance Ratings:
Highly rated for engine power delivery, chassis balance, and suspension performance by professional riders and reviewers.
Emissions Certification:
N/A (Off-road competition vehicles are exempt from typical emissions standards)
