Segment:
High-performance sport ATV
Key Selling Point:
Powerful engine, agile handling, competitive pricing.
Key Competitors:
Honda TRX450R, Suzuki LT-Z400, Kawasaki KFX400.
Manual Benefit 1:
Cost-effective way to maintain vehicle operation.
Manual Benefit 2:
Detailed illustrations and diagrams for clarity.
Manual Benefit 3:
Step-by-step instructions for all repair procedures.
Manual Benefit 4:
Printable pages for use in the workshop.
Manual Benefit 5:
Comprehensive coverage for all aspects of the vehicle.
Engine Mechanical:
Detailed coverage of internal engine components, assembly, disassembly, timing, valve adjustment.
Engine Electrical:
Ignition system, starting system, charging system, CDI unit, wiring diagrams.
Emission Control:
Information related to emission systems and regulations.
Fuel System:
Carburetor (likely Mikuni BSR42), fuel pump, fuel lines, and related components.
Suspension:
Front and rear suspension systems, shock absorbers, control arms, adjustments.
Clutch:
Clutch operation, maintenance, and repair procedures.
Transmission:
Manual transaxle system, gear shifting mechanisms, lubrication.
Drivetrain:
Driveshaft, axles, rear differential (if applicable), chain and sprockets.
Steering:
Steering column, tie rods, steering knuckles, alignment.
Brakes:
Front and rear brake systems, calipers, master cylinders, hydraulic lines, pad replacement.
Body Interior Exterior:
Body panels, plastics, fenders, seat, handlebars, general trim.
Body Electrical:
Lighting system, switches, fuses, battery, wiring harness.
Restraint:
Information related to operator restraint systems (e.g., handgrips, footpegs design).
General Maintenance:
Oil changes, filter replacements, chain adjustments, lubrication points.
Troubleshooting:
Diagnostic procedures for common and uncommon issues.
Engine Repair:
Complete engine rebuild, component replacement, tuning.
Electrical Diagnostics:
Fault finding for electrical systems using wiring diagrams.
Suspension Setup And Repair:
Adjustments, seal replacement, component overhaul.
Brake System Maintenance:
Bleeding, pad/rotor replacement, caliper servicing.
Diagnostic Level:
Advanced, including detailed electrical troubleshooting and wiring schematics.
Repair Complexity:
Comprehensive, from routine maintenance to complete engine and component rebuilds.
Target Audience:
Do-it-yourselfer (DIY) enthusiasts and experienced professional mechanics.
Engine Type:
4-Stroke, Liquid-Cooled, DOHC, 5-Valve, Single Cylinder
Bore X Stroke:
95.0 mm x 63.1 mm (approximate, specific measurements in manual)
Compression Ratio:
11.2:1 (typical for this model)
Carburetor:
Mikuni BSR42 (likely)
Horsepower:
Estimated 40-45 HP (stock, at crank - specific figures in manual)
Torque:
Refer to manual for specific torque figures.
Fuel Type:
Unleaded gasoline
Fuel Tank Capacity:
Approx. 2.6 US gal (9.8 L) (check manual for exact capacity)
Ignition System:
CDI (Capacitor Discharge Ignition)
Length:
Approx. 70.9 in (1800 mm)
Width:
Approx. 45.7 in (1160 mm)
Height:
Approx. 43.7 in (1110 mm)
Wheelbase:
Approx. 49.2 in (1250 mm)
Dry Weight:
Approx. 372 lbs (169 kg)
Curb Weight:
Refer to manual for specific curb weight.
Rack Capacity Front:
Not designed for significant cargo (sport ATV focus)
Rack Capacity Rear:
Not designed for significant cargo (sport ATV focus)
Engine Oil Change:
Every 600 miles or 6 months (refer to manual for exact recommendations and conditions).
Air Filter Cleaning:
More frequently in dusty conditions, inspect every 300 miles or 3 months, clean as needed.
Spark Plug Replacement:
Refer to manual for specific mileage or time interval.
Chain Lubrication Adjustment:
Lubricate every 300 miles or 3 months, check tension regularly.
Engine Oil Type:
Yamalube 4 (or equivalent) SAE 10W-40 API SG or higher.
Engine Oil Capacity:
Approx. 1.90 US qt (1.8 L) without filter change, 2.00 US qt (1.9 L) with filter change (verify in manual).
Coolant Type:
High-quality ethylene glycol-based antifreeze coolant with distilled water (50/50 mix).
Brake Fluid Type:
DOT 4 hydraulic brake fluid.
Common Wear Items:
Clutch plates, brake pads, wheel bearings, steering stem bearings, chain and sprockets.
Carburetor Tuning:
Can be sensitive to altitude and modifications; manual provides detailed tuning procedures.
Engine Decarbonization:
Periodic decarbonization may be recommended for optimal performance.
Yamaha Atv Legacy:
Yamaha has a long-standing reputation for building high-performance and reliable ATVs, dating back to the early '80s with models like the Tri-Moto.
Yfz450 Introduction:
The YFZ450 was a groundbreaking ATV for Yamaha, introduced in 2004, featuring a class-leading 5-valve DOHC engine derived from their WR450F motocross bike, and a lightweight aluminum frame.
Yfz450S Variant:
The 'S' designation typically indicates a specific version or package, though detailed differences between 2003 and 2004 'S' models would be clarified in the manual.
Manufacturing Location:
Likely manufactured in Japan or by Yamaha's global manufacturing partners.
