🏷️ Basic Information Identification Make: Yamaha Model: WR426F Year: 2004 Type: Dual-Sport / Motocross Motorcycle Codes Engine Code: Likely based on the YZ426F engine, specific code not provided but typically an 'SOHC 4-valve' configuration 👋 Introduction Market Position Market Segment: High-performance off-road motorcycle, designed for competition and recreational trail riding. Competitive Analysis Competitors: Competed directly with models like the Honda CR250R/CRF450R, Kawasaki KX250/KX450F, Suzuki RM250/RM-Z450, and KTM EXC/SX models of the era. Key Features Features: Powerful 4-stroke engine, advanced suspension, robust chassis, designed for durability and performance in demanding off-road conditions. 📋 Manual Details Coverage Areas General Coverage: Complete service, repair, maintenance, troubleshooting, and diagnostics for the Yamaha WR426F 2004 model. Page Count Estimated Page Count: N/A (Digital download, page count not specified but described as comprehensive) Manual Type Type: Full Service Repair Manual Language Language: English Format File Format: PDF Delivery Method: Instant Download Printability: Full Printable Requirements Software Requirements: Adobe PDF Reader, WinRAR Compatibility: All Versions of Windows & Mac 📖 Manual Coverage Systems Covered Powertrain: Engine, carburetor, transmission, clutch, gearbox. Chassis: Frame, suspension (front forks, rear shock absorber), wheels, tires, brakes (front and rear), steering. Electrical: Ignition system, lighting, charging system, starter, wiring diagrams, troubleshooting. Bodywork: Plastics, seat, fuel tank, fenders, exhaust system. Procedures Included Maintenance: Regular service, oil changes, filter replacements, lubrication, valve adjustments, chain maintenance. Repair: Engine rebuild, transmission overhauls, suspension repairs, brake system servicing, electrical component replacement. Diagnostics: Troubleshooting common issues, identifying fault causes, diagnostic procedures for electrical and mechanical systems. Rebuilding: Complete engine and component rebuild procedures. Technical Depth Depth: Comprehensive, suitable for professional technicians and experienced DIY mechanics, covering detailed diagnostic and repair procedures. 📊 Manual Specifications File Format Format: PDF Print Quality Quality: High-resolution, suitable for printing individual pages or the entire manual. Binding Type Binding: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type: 4-Stroke, Liquid-Cooled, DOHC, 5-Valve Single Cylinder Displacement: 426cc (Actual displacement 426cc) Bore X Stroke: Approx. 95 mm x 60.8 mm (Specific figures may vary slightly based on exact model variation) Performance Horsepower: Estimated 45-50 HP (at crankshaft, dependent on tuning and exhaust) Torque: Estimated 40-45 Nm (at crankshaft) Fuel System Carburetor: Keihin FCR 39mm (Flat CR) Fuel Type: Unleaded gasoline (Octane rating recommendation typically 91 or higher) Lubrication Oil Type: Yamalube 4T 10W-40 or equivalent high-quality motorcycle specific 4-stroke engine oil Oil Capacity: Approx. 1.1 L (without filter change), 1.2 L (with filter change) 🔧 Transmission Standard Transmission Type: 5-Speed Constant Mesh Optional Clutch Type: Wet, Multiple Disc Features Gear Ratios: Detailed gear ratios are provided within the manual. Final Drive: O-ring sealed chain Transmission Oil: Yamalube 4-stroke motorcycle oil (same as engine oil) or equivalent. Transmission Oil Capacity: Approx. 0.7 L 📐 Dimensions Exterior Overall Length: Approx. 2,170 mm (85.4 in) Overall Width: Approx. 825 mm (32.5 in) Overall Height: Approx. 1,275 mm (50.2 in) Seat Height: Approx. 985 mm (38.8 in) Wheelbase: Approx. 1,475 mm (58.1 in) Weights Dry Weight: Approx. 116 kg (255.7 lbs) Wet Weight: Approx. 121 kg (267 lbs) (with all fluids, excluding fuel) Fuel Tank Capacity: Approx. 8.0 Liters (2.1 US gal) 🛡️ Safety Features Ratings Safety Certification: N/A (Motorcycles are generally not subjected to automotive crash testing standards) Active Features Braking System: Hydraulic disc brakes, front and rear. Suspension: Fully adjustable suspension for optimized handling and rider control. Passive Features Lighting: Headlight, taillight, brake light for visibility. 💡 Technology Features Infotainment Infotainment System: N/A (Basic motorcycle, no electronic infotainment systems) Driver Assistance Assistance Features: N/A (Off-road performance oriented, no rider-assist technologies like ABS or traction control) 🔧 Maintenance Service Intervals Oil Change: Every 1,000 km (600 miles) or 6 months, or more frequently under severe use. Air Filter Cleaning: Every 500 km (300 miles) or after each significant dusty ride. Spark Plug Inspection: Every 1,000 km (600 miles). Valve Clearance Check: Every 4,000 km (2,500 miles). Fluid Specifications Coolant: Permanent type antifreeze coolant (50% mixture with distilled water). Brake Fluid: DOT 4 hydraulic brake fluid. Known Issues Common Problems: Carburetor tuning sensitivity, occasional cam chain noise (especially with high mileage), wear on suspension components, kickstart mechanism wear. Overheating under extreme conditions if cooling system is not maintained. 📚 Vehicle History Brand Heritage Heritage: Yamaha has a long-standing history in off-road racing and motorcycle development, with the WR series building upon their successful YZ motocross platforms. Model Evolution Evolution: The WR426F was a significant model in Yamaha's transition to 4-stroke off-road competition, following earlier 2-stroke models and preceding the fuel-injected WR450F. It offered a potent blend of torque and power. Production Production Years: The WR426F was produced from approximately 2001 to 2002. The 2004 model information in the product name likely refers to a manual that also covers related models or perhaps is a common aftermarket manual designation that might include earlier...