Market Segment:
Utility ATV, Entry-level/Mid-range
Key Competitors 1999:
Honda FourTrax 300, Suzuki QuadRunner 250, Kawasaki Bayou 220
Target User:
Recreational riders, light farm work, trail riding
Manual Benefit:
Enables users to perform maintenance, repairs, and understand the vehicle for problem prevention.
Coverage Areas:
General Information, Specifications, Periodic Inspections and Adjustments, Engine Overhaul, Chassis, Drive Train, Carburation, Electrical, Troubleshooting
Manual Type:
Digital Service Repair Manual
Manual Completeness:
Full service and repair manual, not a condensed version.
Systems Covered:
Engine, Fuel System (Carburetor), Drivetrain (Transmission, Final Drive), Chassis, Suspension, Brakes, Electrical System (Ignition, Lighting, Starting), Troubleshooting
Procedures Included:
Routine Maintenance, Component Overhaul, Repair Procedures, Diagnostic Steps, Troubleshooting Guides, Adjustment Procedures
Suspension Service:
Front and rear suspension inspection, lubrication, shock absorber replacement, and adjustment procedures.
Carburetor Overhaul:
Step-by-step disassembly, cleaning, reassembly, jetting specifications, float adjustment, and idle speed settings.
Technical Depth:
Comprehensive (from basic adjustments to full engine rebuilds)
Engine Rebuild Scope:
Complete engine disassembly, inspection, component replacement (pistons, rings, valves, seals, gaskets), and reassembly.
Troubleshooting Methodology:
Systematic diagnostic charts and flowcharts for common and uncommon issues, covering engine performance, electrical faults, and drivetrain problems.
Electrical System Details:
Wiring diagrams, starter system, charging system (stator, regulator/rectifier), lighting circuits, ignition system components.
Viewing Requirements:
Adobe PDF Reader or equivalent
Operating System Compatibility:
All Versions of Windows & Mac, Smartphones, Tablets
Extraction Method:
Standard file extraction (e.g., WinZip)
Searchability:
Likely text-searchable within PDF reader, depending on original document quality.
Engine Type:
Four-stroke, SOHC
Displacement:
230cc (approx.)
Bore X Stroke:
70.0 mm x 64.0 mm (typical for this displacement class, manual will confirm exact)
Cooling System:
Air-cooled
Horsepower Estimate:
15-20 HP (estimated, manual will provide specific rating)
Torque Estimate:
14-17 lb-ft (estimated, manual will provide specific rating)
Fuel Delivery:
Carburetor
Carburetor Model Estimate:
Mikuni VM Series (typical for Yamaha, manual will confirm specific model and jetting)
Fuel Type:
Unleaded gasoline
Oil Type:
Yamalube 4 (or equivalent SAE 10W-30 API SE, SF, or SG classification) - Manual will specify exact.
Oil Capacity:
Approx. 1.5 Liters (Manual will confirm exact capacity with/without filter change).
Ignition System:
CDI (Capacitor Discharge Ignition)
Spark Plug Type Estimate:
NGK CR6HSA (Manual will confirm exact plug and gap).
Transmission Type:
Automatic (CVT - Continuously Variable Transmission)
Drive System:
2WD (Two-Wheel Drive)
Gear Selection:
Forward, Neutral, Reverse
Transmission Fluid Type:
Yamaha Gear Oil (or equivalent SAE 80W API GL-4) - Manual will specify exact.
Transmission Fluid Capacity:
Approx. 0.2 Liters (Manual will confirm exact capacity).
Length:
Approx. 72.8 inches (Manual will provide precise measurement)
Width:
Approx. 41.3 inches (Manual will provide precise measurement)
Height:
Approx. 42.1 inches (Manual will provide precise measurement)
Dry Weight:
Approx. 463 lbs (Manual will confirm exact)
Fuel Capacity:
Approx. 2.6 Gallons (Manual will confirm exact)
Front Tire Size:
AT 23x8-12 (Manual will confirm exact)
Rear Tire Size:
AT 22x10-10 (Manual will confirm exact)
Wheel Bolt Pattern Estimate:
4x110mm (typical for Yamaha ATVs of this era, manual will confirm)
Atv Safety Standards:
Compliant with ANSI/SVIA 1-2001 standards (as mandated for US models)
Braking System:
Hydraulic disc brakes front and rear
Parking Brake:
Mechanical parking brake, typically lever-actuated on rear brake.
Throttle Limiter:
Thumb throttle with return spring
Kill Switch:
Engine shut-off switch on handlebars
Display Features:
Basic LCD display showing odometer, trip meter, neutral indicator, high beam indicator.
Throttle Control:
Ergonomic thumb throttle for precise speed control.
Charging Port:
Typically a 12V accessory outlet or battery tender lead for charging accessories or maintaining battery charge.
Oil Change Interval:
Every 1,000 km or 6 months (Manual will confirm specific interval and conditions)
Air Filter Cleaning:
Every 500 km or as needed based on operating conditions (Manual will confirm)
Spark Plug Inspection:
Every 1,000 km (Manual will confirm)
Valve Clearance Adjustment:
Every 2,000 km or 1 year (Manual will confirm)
Engine Oil Spec:
SAE 10W-30 API SE, SF, or SG Classification (Yamalube 4 recommended)
Gear Oil Spec:
SAE 80W API GL-4 Gear Oil (Yamaha Gear Oil recommended)
Common Wear Items:
Brake pads, wheel bearings, CV joint boots, carburetor jets (prone to clogging if fuel is stale).
Carburetor Tuning:
Difficulty starting, rough idle can often be resolved by cleaning and proper adjustment of the carburetor.
Electrical Connections:
Corrosion on electrical connectors can lead to intermittent issues, especially in wet environments.
Drive Belt Wear:
While shaft drive, maintenance on U-joints and differentials is critical for longevity.
Parent Company:
Yamaha Motor Corporation, Japan
Timberwolf Lineage:
The Timberwolf was Yamaha's entry into the mid-size utility ATV market, known for its reliability and ease of use.
Production Period:
The YFB 250 Timberwolf was produced from the mid-1990s through the early 2000s, with the 1999 model representing a significant iteration.
