Vehicle Class:
Lightweight Off-Road Motorcycle / Trail Bike
Target Demographic:
Beginner to intermediate riders, youth riders, recreational trail riders.
Key Competitors:
Honda CRF150F, Kawasaki KLX140, Suzuki DR-Z125
Vehicle Usp:
Reliability, ease of use, affordability, versatility for various trail conditions.
Engine Systems:
Top End (Cylinder, Piston, Valve Train), Bottom End (Crankshaft, Connecting Rod), Carburetion, Ignition System, Cooling System (if applicable, though typically air-cooled for this model), Exhaust System, Lubrication System
Chassis Systems:
Frame, Suspension (Front Fork, Rear Shock Absorber), Steering System, Braking System (Front & Rear), Wheel & Tire Information, Drive Chain & Sprockets, Swingarm
Electrical Systems:
Wiring Diagrams, Lighting System, Ignition System (CDI), Battery, Starting System (if electric start equipped), Indicators
Maintenance Procedures:
Oil Change, Air Filter Cleaning/Replacement, Spark Plug Service, Chain Adjustment & Lubrication, Brake Adjustment, Clutch Adjustment, Valve Clearance Adjustment, Carburetor Cleaning & Adjustment
Repair Procedures:
Engine Rebuild (Top & Bottom End), Carburetor Overhaul, Suspension Fork Seal Replacement, Shock Absorber Service, Brake System Bleeding & Pad Replacement, Clutch Assembly Service, Wheel Bearing Replacement, Electrical Component Diagnosis & Replacement
Troubleshooting Diagnostics:
Step-by-step diagnostic procedures for common performance issues, starting problems, electrical faults, and braking issues.
Depth Of Information:
Comprehensive, covering everything from basic pre-ride checks and routine maintenance to complete engine and chassis teardowns and rebuilds. Includes detailed torque specifications, clearances, and diagnostic flowcharts.
Engine Type:
Air-cooled, four-stroke, SOHC, two-valve
Bore X Stroke:
54 mm x 54.5 mm
Horsepower Estimate:
Approx. 10-12 HP @ 7500 RPM (varies slightly by model year and tuning)
Torque Estimate:
Approx. 7.5-8.5 lb-ft @ 6000 RPM (varies slightly by model year and tuning)
Fuel Delivery:
Carburetor
Carburetor Model:
Mikuni VM20SS (typical)
Fuel Type:
Unleaded gasoline (minimum 87 octane recommended)
Ignition Type:
CDI (Capacitor Discharge Ignition)
Lubrication Type:
Wet sump
Oil Capacity:
Approx. 1.0 Liters (0.87 US qt) (check manual for exact specification)
Starting Method:
Kick starter (standard on all models). Electric start available on TTR125E and TTR125LE models.
Transmission Type:
Constant mesh, 5-speed sequential
Clutch Type:
Wet, multi-plate
Gear Ratios:
Detailed gear ratios are provided in the manual (e.g., 1st: 2.833, 2nd: 1.706, 3rd: 1.300, 4th: 1.045, 5th: 0.870)
Transmission Oil Type:
Yamaha's recommended Yamalube (or equivalent API SG, SAE 10W-40 or 20W-40)
Overall Length:
Approx. 1835 mm (72.2 in)
Overall Width:
Approx. 775 mm (30.5 in)
Overall Height:
Approx. 1095 mm (43.1 in)
Seat Height:
Approx. 780 mm (30.7 in)
Wheelbase:
Approx. 1275 mm (50.2 in)
Wet Weight:
Approx. 104 kg (229 lbs) (varies by model variant, TTR125LE with electric start will be slightly heavier)
Fuel Tank Capacity:
6.0 Liters (1.6 US gal)
Front Suspension Type:
Telescopic fork
Front Fork Travel:
Approx. 170 mm (6.7 in)
Rear Suspension Type:
Swingarm, Monocross suspension
Rear Shock Travel:
Approx. 180 mm (7.1 in)
Front Tire Size:
70/100-19 42M
Rear Tire Size:
90/100-16 51M
Wheelbase Bolt Pattern:
Not applicable (motorcycle spoked wheels)
Crash Test Ratings:
Not applicable (motorcycle off-road use)
Braking System:
Front: Disc brake. Rear: Drum brake (standard for this class of bike).
Lighting:
Headlight, Taillight, Stoplight, Turn Signals (depending on regional compliance and model variant)
Throttle Limiter:
May be present on some models for younger riders (adjustable)
Oil Change Interval:
Every 1,000 km (600 miles) or 6 months (refer to manual for exact specification based on usage)
Air Filter Service:
Every 500 km (300 miles) or as needed based on dusty conditions.
Spark Plug Service:
Every 1,000 km (600 miles) or annually.
Valve Clearance Check:
Every 5,000 km (3,000 miles) or annually.
Engine Oil Specification:
API SG, SAE 10W-40 or 20W-40 (Yamalube recommended)
Fork Oil Type:
Specific weight and quantity detailed in the manual (e.g., Yamalube Fork Oil 10W or equivalent)
Common Wear Items:
Clutch plates, brake pads, chain and sprockets, wheel bearings, spark plug, air filter.
Potential Problems:
Carburetor clogging if not maintained, kick starter mechanism wear, potential for valve seat recession with very high mileage or poor fuel quality (though generally robust).
Oil Filter Part Number:
Internal screen filter (no disposable cartridge filter on this model)
Air Filter Part Number:
Yamaha P/N: 5FU-14451-00-00 or equivalent aftermarket
Yamaha Legacy:
Yamaha has a long-standing reputation for producing reliable and capable off-road motorcycles, from small-displacement beginner bikes to professional motocross machines.
Ttr Lineage:
The TTR line is Yamaha's durable and user-friendly entry-level off-road platform, known for its accessibility and robust engineering.
Production Years Covered:
2000-2006 (with this manual specifically covering 2005-2006)
Manufacturing Origin:
Typically manufactured in Japan or other Yamaha global facilities.
Model Awards:
While specific awards for the TTR 125 are rare, the model consistently receives praise in enthusiast reviews for its reliability, ease of use, and value as an entry-level trail bike.
Durability Rating:
High (due to simple, robust design and Yamaha's manufacturing quality)
