Basic Information Identification Make: Yamaha Model: Big Bear 400 Model Codes: YFM400FWNP, YFM400FWNM, YFM400NM Model Years Covered: 2000, 2001, 2002, 2003, 2004, 2005, 2006 Introduction Market Position Quad Type: Utility ATV Target User: Recreational riders, farm use, trail riding. Competitive Analysis Competitors: Honda FourTrax, Suzuki King Quad, Arctic Cat (competitors in the utility ATV segment during that era). Key Features Engine Type: Reliable 4-stroke, liquid-cooled engine. Drivetrain Type: Selectable 4WD (Four-Wheel Drive) with a 2WD option for different terrains. Transmission: Automatic transmission (V-belt, CVT type) with high/low range and reverse. Suspension Type: Independent front suspension for improved ride comfort and handling. Braking System: Robust disc brake system for effective stopping power. Manual Details Coverage Areas Manual Type: Shop Manual / Service & Repair Manual Language: English Format: PDF Download Device Compatibility: PC, MAC, Tablets, Smartphones Manual Coverage Systems Covered Engine Mechanical: Complete engine overhaul, including cylinder head, pistons, crankshaft, camshaft, valve train, and lubrication system. Engine Electrical: Ignition system (CDI, spark plug), starting system (starter motor, starter clutch), charging system (stator, regulator/rectifier), and wiring diagrams. Fuel System: Carburetor (Mikuni BSR33) specifications, cleaning, adjustment, fuel pump, fuel tank, and fuel lines. Transmission Drivetrain: 5-speed constant mesh transmission, automatic centrifugal clutch, final drive (shaft drive), differential, and driveshaft. Suspension: Front independent double-wishbone suspension, rear swingarm suspension, shock absorbers, and related components. Brakes: Front and rear hydraulic disc brakes, brake caliper service, brake lines, master cylinders, and brake fluid. Steering: Handlebar steering mechanism, tie rods, steering knuckle, and wheel alignment. Electrical System Components: Headlight, taillight, brake lights, indicators, battery, fuses, switches, and control units. Frame Chassis: Frame inspection, welds, and related chassis components. Bodywork Trim: Fender removal and installation, seat, fuel tank cover, and plastic trim components. Procedures Included Maintenance Schedules: Detailed recommended maintenance intervals for oil changes, filter replacement, valve adjustments, and more. Troubleshooting: Comprehensive diagnostic procedures for common and uncommon issues, symptom-based troubleshooting charts. Repair Procedures: Step-by-step instructions for all major component repairs and replacements. Rebuild Instructions: Detailed procedures for engine and transmission rebuilds. Wiring Diagrams: Complete and clear electrical wiring schematics for easy diagnosis and repair. Torque Specifications: Essential torque values for all critical fasteners and bolts. Special Tool Requirements: Identification of any specialized tools needed for specific procedures. Technical Depth Depth Level: Professional and in-depth, suitable for both novice mechanics and experienced technicians. Diagnostic Capability: Enables advanced diagnostics and systematic troubleshooting. Component Level Detail: Covers repair and overhaul down to individual component level. Manual Specifications File Format File Type: PDF (Portable Document Format) Searchability: Searchable text for quick information retrieval. Print Quality Resolution: High-resolution for clear diagrams and text. Scalability: Scalable for viewing on various screen sizes. Binding Type Binding: N/A (Digital Download) Paper Type Paper: N/A (Digital Download) Engine Specifications Primary Engine Engine Type: SOHC (Single Overhead Cam), 4-stroke, 5-valve, liquid-cooled, single-cylinder Engine Displacement: 386 cc (cubic centimeters) Bore X Stroke: 84.0 mm x 70.0 mm (approximate) Performance Horsepower: Estimated 21-23 HP (Horsepower) at around 5500 RPM (exact figures may vary by year and tuning). Torque: Estimated 23-25 lb-ft (pound-feet) at around 4500 RPM (exact figures may vary). Fuel System Fuel Delivery: Carburetor (Mikuni BSR33) Fuel Type: Unleaded gasoline Lubrication Oil Type: Yamalube 4 (or equivalent SAE 10W-40 API SG or higher) motorcycle oil. Oil Capacity: Approximately 2.2 liters (2.3 US qt) with filter change (refer to manual for exact capacity). Ignition Ignition System: CDI (Capacitor Discharge Ignition) Spark Plug: NGK CR7E (or equivalent - always verify with manual) Transmission Standard Transmission Type: Automatic (V-belt, CVT - Continuously Variable Transmission) Optional Gear Selection: High range (H), Low range (L), Neutral (N), Reverse (R). Features Clutch Type: Automatic centrifugal clutch Final Drive: Shaft drive with differential Transmission Fluid Type: Yamaha Genuine Gear Oil API GL-4 SAE 80W (or equivalent). Capacity approximately 0.13 L (0.14 US qt). Dimensions Exterior Overall Length: Approximately 77.2 inches (1960 mm) Overall Width: Approximately 43.1 inches (1095 mm) Overall Height: Approximately 45.5 inches (1155 mm) Wheelbase: Approximately 49.2 inches (1250 mm) Weights Dry Weight: Approximately 570 lbs (259 kg) - curb weight will be higher. Curb Weight: Typically around 590-600 lbs (268-272 kg) with all necessary fluids. Cargo Front Rack Capacity: Approximately 45 kg (99 lbs) Rear Rack Capacity: Approximately 85 kg (187 lbs) Tires Front Tire Size: AT25x8-12 Rear Tire Size: AT25x10-12 Wheels Wheel Bolt Pattern: Not applicable (hub-centric wheel mounting) Safety Features Ratings Atv Safety: Riders should always wear appropriate safety gear, including a helmet, goggles, gloves, and sturdy footwear. Follow all operational guidelines and terrain recommendations. Active Features Braking System: Hydraulic disc brakes on all wheels for reliable stopping power. Drivetrain Selection: Selectable 2WD/4WD for adapting to various traction conditions. Passive Features Handlebars: Ergonomically designed handlebars for control and comfort. Lighting: Dual 30W headlights, 30/30W brakelight/taillight for visibility. Technology Features Infotainment Infotainment System: Basic utility ATV, no integrated infotainment system. Driver Assistance...