Target User:
ATV enthusiasts, DIY mechanics, repair shops, and owners seeking to maintain or repair their Yamaha Bruin.
Value Proposition:
Provides comprehensive, authoritative technical guidance to enable owners to perform a wide range of maintenance and repair tasks, saving on labor costs and ensuring proper vehicle function.
Competitor Manuals:
This manual competes with factory service manuals, other aftermarket repair guides, and online forums by offering a consolidated, detailed, and officially recognized source of information.
Detail Level:
Extremely high level of detail, covering everything from routine checks to complete overhauls.
Organization:
Features a comprehensive table of contents for easy navigation and quick access to specific information.
Illustrations Diagrams:
Implied to contain numerous illustrations and diagrams to aid in understanding complex procedures.
Engine:
Detailed diagnostics, repair, rebuild procedures for all engine components, including top-end, bottom-end, cooling system, lubrication system, and ignition system.
Transmission:
Coverage for transmission inspection, disassembly, reassembly, adjustments, and fluid specifications.
Drivetrain:
Front and rear differential service, drive shafts, CV joints, and wheel hub maintenance.
Suspension:
Front and rear suspension component inspection, replacement, and alignment procedures.
Brakes:
Brake system diagnostics, master cylinder, caliper, rotor, brake line, and bleeding procedures.
Steering:
Steering column, tie rods, rack and pinion, and steering column adjustments.
Electrical System:
Battery, charging system (stator, regulator/rectifier), starting system, lighting, instrumentation, and wiring diagrams.
Fuel System:
Carburetor service and adjustment, fuel pump, fuel lines, and fuel tank maintenance.
Cooling System:
Radiator, fan, thermostat, water pump, and coolant specifications.
Exhaust System:
Muffler, exhaust pipes, and gasket replacement.
Body And Frame:
Chassis inspection, body panel removal and installation, seat, and rack components.
Maintenance:
Scheduled maintenance, oil changes, filter replacements, lubrication points, and general upkeep.
Troubleshooting:
Diagnostic charts for common problems and their solutions across all vehicle systems.
Repair:
Step-by-step repair instructions for virtually every component and system on the ATV.
Rebuild:
Detailed procedures for complete engine and transmission rebuilds.
Disassembly Reassembly:
Comprehensive guidance for taking apart and putting back together all major vehicle assemblies.
Wiring Diagrams:
High-quality, detailed wiring schematics for accurate electrical troubleshooting and repair.
Diagnostic Tools:
Information on required tools, specialized equipment, and diagnostic procedures.
Torque Specifications:
Precise torque values for all fasteners and critical components.
Clearances And Tolerances:
Specifications for critical component clearances and wear tolerances.
Service Limits:
Information on component wear limits and when parts should be replaced.
Performance Tuning:
While not primarily a tuning manual, it provides the baseline specifications for proper engine operation.
Engine Type 350:
348cc, 4-stroke, SOHC, 2-valve, air-cooled, single-cylinder
Engine Type 400:
386cc, 4-stroke, SOHC, 2-valve, liquid-cooled, single-cylinder
Bore X Stroke 350:
83 mm x 64.5 mm (approximate, requires manual verification)
Bore X Stroke 400:
94 mm x 69 mm (approximate, requires manual verification)
Compression Ratio 350:
9.2:1 (typical, requires manual verification)
Compression Ratio 400:
8.8:1 (typical, requires manual verification)
Horsepower 350:
Approx. 17-20 HP (requires manual verification)
Horsepower 400:
Approx. 21-24 HP (requires manual verification)
Torque 350:
Approx. 18-20 lb-ft (requires manual verification)
Torque 400:
Approx. 23-25 lb-ft (requires manual verification)
Fuel Delivery 350:
Mikuni BSR33 carburetor
Fuel Delivery 400:
Mikuni BSR33 carburetor
Fuel Type:
Unleaded gasoline, minimum 87 octane
Transmission Type:
Automatic (Ultramatic®), V-belt, automatic transmission
Gear Selection:
High, Low, Neutral, Reverse
Transmission Options:
N/A (all models in this range feature the Ultramatic® transmission)
Drive System:
2WD/4WD selectable, shaft drive
Final Drive:
Sealed chain, sprockets, and drive shafts
Length:
Approx. 76.4 in (1940 mm) (requires manual verification)
Width:
Approx. 44.3 in (1125 mm) (requires manual verification)
Height:
Approx. 44.1 in (1120 mm) (requires manual verification)
Wheelbase:
Approx. 49.2 in (1250 mm) (requires manual verification)
Front Rack Capacity:
Approx. 88 lbs (40 kg) (requires manual verification)
Rear Rack Capacity:
Approx. 176 lbs (80 kg) (requires manual verification)
Dry Weight 350:
Approx. 525 lbs (238 kg) (requires manual verification)
Dry Weight 400:
Approx. 569 lbs (258 kg) (requires manual verification)
Towing Capacity:
Approx. 1,124 lbs (510 kg) (requires manual verification)
Engine Oil Change:
Every 1,000 km or 6 months (typical, consult manual for precise interval).
Air Filter Cleaning:
Every 300 km or as needed in dusty conditions (consult manual).
Spark Plug Inspection:
Every 1,000 km or 6 months (consult manual).
Gear Oil Change:
Every 6,000 km or 2 years (typical, consult manual).
Engine Oil Type:
Yamalube 4 (or equivalent) SAE 10W-40 API SG or higher (consult manual for exact specification).
Engine Oil Capacity:
Approx. 1.7 L / 1.8 US qt (without filter change), 1.9 L / 2.0 US qt (with filter change) (requires manual verification).
Coolant Type 400:
Yamaha Coolant 50% or equivalent ethylene glycol-based coolant (requires manual verification).
Coolant Capacity 400:
Approx. 1.7 L / 1.8 US qt (requires manual verification).
Common Wear Items:
CV boots, brake pads, tires, battery, and drive belts are common wear items requiring periodic inspection and replacement.
Carburetor Cleaning:
Carburetors may require periodic cleaning and adjustment, especially if the ATV is stored for extended periods.
Charging System Issues:
Stator or regulator/rectifier failures can occur, impacting battery charging. Manual provides diagnostic steps.
Yamaha Legacy:
Yamaha Motor Corporation is renowned for its long history in motorsports, motorcycles, and marine engines, bringing a legacy of engineering and reliability to its ATV line.
Bruin Introduction:
The Bruin series was Yamaha's entry into the mid-size utility ATV market, offering a balance of power, comfort, and capability.
Model Differences:
The 350 model offered a lighter, air-cooled engine for basic utility tasks, while the 400 provided increased power and liquid cooling for more demanding applications.
Manufacturing Location:
Typically manufactured in Japan or by Yamaha's global manufacturing partners.
Model Successors:
The Bruin was succeeded by Yamaha's Grizzly line, which incorporated more advanced features and performance.
