🏷️ Basic Information Identification Make: KTM Model: 85sx / 105sx Product Name: KTM 85sx/105sx Service Manual Repair 2004-2009 Vehicle Type: Off-road Motorcycle / Motocross 👋 Introduction Market Position Market Position: The KTM 85sx and 105sx are highly regarded in the youth motocross segment, known for their performance and race-oriented design. This manual serves riders and mechanics aiming to maintain or restore these competitive machines. Competitive Analysis Competitive Analysis: Competes directly with models from brands like Yamaha (YZ85), Kawasaki (KX85), and Suzuki (RM85). The KTMs often differentiate themselves with European engineering and a focus on aggressive power delivery. Key Features Key Features: Factory-level technical information, comprehensive coverage of critical components (engine, suspension), and detailed procedures for common maintenance and repair tasks. 📋 Manual Details Coverage Applicable Years: 2004, 2005, 2006, 2007, 2008, 2009 Covered Models: KTM 85sx, KTM 105sx Page Count Page Count: 246 pages Manual Type Manual Type: Factory Service Manual / Repair Manual / Owner's Manual / Rebuild Manual Format Format: PDF (Digital Download) Language Language: English Features Searchable: Yes Print Restrictions: None Saving Restrictions: None 📖 Manual Coverage Systems Covered Engine: Complete engine tear down, rebuild, troubleshooting, specifications. Transmission: Gearbox inspection, repair, and maintenance. Suspension Front: Front fork rebuild, maintenance, fluid specifications, assembly. Suspension Rear: Rear shock absorber rebuild, maintenance, charging, linkage system. Fuel System: Carburetor (jetting, cleaning, adjustment), fuel lines, fuel tank. Electrical System: Ignition system, stator, magneto, wiring diagrams, switches. Brakes: Front and rear brake systems, caliper service, pad replacement, fluid checks. Bodywork And Plastics: Panel removal and installation, fender maintenance. Wheels And Tires: Tire pressure, wheel bearing service, spoke tension. Cooling System: Radiator maintenance, coolant type, flushing procedures. Exhaust System: Muffler and pipe inspection. Clutch: Clutch operation, maintenance, and adjustments. Procedures Included Maintenance: Scheduled maintenance, fluid changes, filter replacements, lubrication. Repair: Complete engine, transmission, suspension, and chassis repairs. Rebuild: Detailed step-by-step rebuild instructions for major components like the engine, front forks, and rear shock. Troubleshooting: Diagnostic charts, common problems and their solutions, error code interpretation (if applicable). Installation: Guidance on installing replacement parts and accessories. Adjustment: Carburetor mixture screws, throttle cables, clutch levers, chain tension. Technical Depth Depth: Comprehensive from basic maintenance to complete engine and suspension overhauls. Includes detailed diagrams and torque specifications for precise assembly. 📊 Manual Specifications File Format File Format: Portable Document Format (PDF) Print Quality Image Resolution: High-resolution images and diagrams for clarity. Binding Type Binding Type: N/A (Digital File) Paper Type Paper Type: N/A (Digital File) ⚙️ Engine Specifications Primary Engine Engine Type: Two-stroke, single-cylinder Displacement 85Sx: 85cc Displacement 105Sx: 105cc Bore Stroke 85Sx: Approx. 47mm x 48.6mm Bore Stroke 105Sx: Approx. 52.5mm x 48.6mm Cooling System: Liquid-cooled Ignition System: Digital CDI Performance Horsepower Estimate: Varies by year and specific tuning, typically in the 20-25 HP range for the 85cc. Torque Estimate: Not typically quoted in standard specs, but designed for strong low-to-mid range power. Fuel System Carburetor Model: Mikuni VM28 (common for these years, specific model may vary slightly) Fuel Type: Unleaded gasoline with appropriate two-stroke oil pre-mix Premix Ratio: Typically 40:1 or 50:1, check specific manual recommendations. 🔧 Transmission Standard Transmission Type: 6-speed manual constant mesh Features Clutch Type: Hydraulic actuated wet multi-plate clutch 📐 Dimensions Weights Dry Weight 85Sx: Approx. 66 kg (145.5 lbs) Dry Weight 105Sx: Approx. 70 kg (154.3 lbs) Fuel Tank Capacity: Approx. 5.5 liters (1.45 gallons) 🔧 Maintenance Service Intervals Oil Change Interval: Gearbox oil: Recommended every 10-15 hours of riding. Refer to manual for exact procedure and oil type. Air Filter Cleaning: Clean and re-oil after every few rides or as needed, depending on conditions. Spark Plug Replacement: Inspect regularly, replace as needed based on condition. NGK BR10EG or equivalent. Top End Rebuild: Recommended between 40-60 hours of riding for optimal performance and reliability. Fluid Specifications Gearbox Oil Type: SAE 80 or 85W motocross gear oil. Check manual for specific API GL classification (e.g., GL-4). Coolant Type: High-quality ethylene glycol based coolant with corrosion inhibitors. Typically a 50/50 mix with distilled water. Fork Oil Type: Specific viscosity and volume for front forks (e.g., WP Suspension Fork Oil 7.5W or equivalent). Check manual for precise specs. Brake Fluid Type: DOT 4 or DOT 5.1 hydraulic brake fluid. Known Issues Known Issues: Common wear items include piston rings, clutch plates, and wheel bearings. Suspension seals can also require periodic replacement. Proper maintenance is key to preventing premature wear. Carburetor Tuning: Can be sensitive to altitude and temperature changes, requiring occasional jetting adjustments. 📚 Vehicle History Brand Heritage Brand Heritage: KTM, 'Ready to Race', has a strong heritage in off-road racing, particularly motocross and enduro. This philosophy is evident in the performance-oriented design of the 85sx and 105sx models. Model Evolution Model Evolution: The 85sx has been a staple in KTM's youth lineup, evolving through various chassis and engine updates to maintain its competitive...