🏷️ Basic Information Identification Make: Yamaha Model: Big Bear 400 Model Years Covered: 2000, 2001, 2002, 2003, 2004 Codes Chassis Codes: YFM400F (4x4), YFM400 (4x2) 👋 Introduction Market Position Positioning: The Yamaha Big Bear 400 was positioned as a rugged, reliable utility ATV for work and recreational trail riding, known for its comfort and capability. Competitive Analysis Competitors: Competed with models like the Honda Foreman 400/450, Suzuki Vinson 500, and Kawasaki Prairie 360/400. Key Features Features: Independent front suspension (IFS), automatic transmission, reliable single-cylinder engine, durable build quality, excellent towing and carrying capacity. Value Proposition Manual Value: This workshop manual provides essential information for maintaining the longevity and performance of the Yamaha Big Bear 400, covering all critical repair and service procedures. 📋 Manual Details Coverage Areas Primary Coverage: Complete Service, Repair, Maintenance, Troubleshooting, Diagnostics Secondary Coverage: Wiring Diagrams, Specifications, Exploded Views, Assembly/Disassembly Procedures Page Count Estimated Page Count: Hundreds of pages (specific count not provided, but indicative of comprehensive coverage) Manual Type Type: Workshop Service Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine: Complete overhaul, inspection, tuning, carburetor, cooling system, lubrication Transmission: Clutch, gearbox, final drive, drive shafts, differential (where applicable) Chassis: Frame, suspension (front and rear), steering, wheels, tires Brakes: Hydraulic system, calipers, master cylinder, brake lines, parking brake Electrical: Ignition system, lighting, starting system, charging system, battery, wiring diagrams Bodywork: Body panels, fenders, racks, seat, plastics Procedures Included Maintenance: Oil changes, filter replacements, spark plug service, valve adjustments, lubrication points Repair: Engine rebuilds, transmission repairs, suspension component replacement, brake system overhaul Troubleshooting: Diagnostic flowcharts, fault finding for engine, electrical, and mechanical issues Diagnostics: Component testing, electrical system diagnosis, performance checks Technical Depth Depth: Comprehensive factory-level detail, suitable for professional technicians and advanced DIY users Detail Level: Includes step-by-step instructions, torque specifications, clearances, and special tool requirements 📊 Manual Specifications File Format Format: PDF Searchability: Likely text-searchable within the PDF Print Quality Printability: Designed for printing individual pages or sections as needed Binding Type Binding Type: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type: 4-stroke, SOHC, air-cooled Displacement: 386cc Bore X Stroke: 83 mm x 71 mm Compression Ratio: 8.6:1 Performance Horsepower: Approx. 20-22 HP (at crankshaft, estimated) Torque: Approx. 22-24 lb-ft (at crankshaft, estimated) Fuel System Fuel Delivery: Carburetor (Mikuni BSR33) Fuel Type: Unleaded gasoline, 87 octane minimum Ignition Ignition System: CDI (Capacitor Discharge Ignition) Lubrication Oil Type: Yamalube 4 (or equivalent API SE, SF, SG, SH, SJ or higher, SAE 10W-40 or 20W-50) Oil Capacity W Filter: 2.20 Liters (2.32 US qt) Cooling System Cooling Method: Air-cooled with oil cooler 🔧 Transmission Standard Type: Automatic (Yamaha Ultramatic®) Drive System: Shaft drive (2WD/4WD selectable) Features Gear Selection: High, Low, Neutral, Reverse, Park Fluid Specifications Transmission Fluid: Yamalube SAE 10W-30 API SF (or equivalent) Transmission Fluid Capacity: 0.70 Liters (0.74 US qt) 📐 Dimensions Exterior Length: 2000mm (78.7 in) Width: 1120mm (44.1 in) Height: 1150mm (45.3 in) Wheelbase: 1260mm (49.6 in) Ground Clearance: 235mm (9.3 in) Weights Dry Weight: 253 kg (558 lbs) for 4x4 Curb Weight: 277 kg (611 lbs) for 4x4 (approx.) Cargo Front Rack Capacity: 90 kg (200 lbs) Rear Rack Capacity: 180 kg (400 lbs) Towing Capacity: 500 kg (1102 lbs) Wheels And Tires Front Tire Size: AT25x8-12 Rear Tire Size: AT25x10-12 Wheel Bolt Pattern: 4-stud, 110mm PCD (typical for Yamaha ATVs) 🛡️ Safety Features Ratings Atv Safety Standards: Designed and manufactured to meet current ANSI/SVIA safety standards. Active Features Selectable 4Wd: Provides enhanced traction for challenging terrain. Engine Braking: Ultramatic transmission provides inherent engine braking for descents. Passive Features Lighting: Dual 30W halogen headlights, 15W taillight/stoplight. Ergonomics: Comfortable seat and handlebar positioning for rider control. 💡 Technology Features Infotainment Infotainment System: N/A (Utility ATV) Driver Assistance Driver Assistance: N/A (Utility ATV) Connectivity Connectivity: N/A (Utility ATV) Instrumentation Dashboard Features: Speedometer, odometer, trip meter, neutral indicator, reverse indicator, 2WD/4WD indicator, high/low gear indicator. 🔧 Maintenance Service Intervals Initial Service: First service typically recommended at 1000 km (600 miles) or 6 months, whichever comes first. Engine Oil Change: Every 1000 km (600 miles) or 6 months. Air Filter Cleaning: Every 1000 km (600 miles) or annually, more frequently in dusty conditions. Spark Plug Replacement: Check every 2000 km (1200 miles) or annually; replace as needed (NGK CR7E or equivalent). Valve Clearance Check: Check every 4000 km (2400 miles) or 2 years. Fluid Specifications Brake Fluid: DOT 3 or DOT 4 hydraulic brake fluid. Coolant Type: N/A (Air-cooled engine) Known Issues Common Wear Items: CV joint boots, brake pads, wheel bearings, carburetor jets (can clog). Carburetor Tuning: Carburetors can sometimes require adjustment or cleaning due to fuel variability or age. Suspension Bushings: Rubber suspension bushings can degrade over time and require replacement for optimal handling. 📚 Vehicle History Brand Heritage...