Segment:
Entry-level to intermediate off-road/trail motorcycle.
Target Audience:
Young riders, recreational trail riders, beginner motocross racers.
Key Competitors:
Honda CRF100F/XR100R, Kawasaki KLX110, Suzuki DR-Z125.
Vehicle Strengths:
Reliable air-cooled engine, easy to ride, durable, available in kick-start and electric-start variants, long-travel suspension on LW models.
Manual Value Proposition:
Provides in-depth technical knowledge for owners and mechanics to maintain and repair the 2004 TT-R125 series, maximizing performance and longevity.
Primary Focus:
Service, Repair, Maintenance, Troubleshooting, Specifications
Model Variants Covered:
2004 Yamaha TT-R125, TT-R125E (Electric Start), TT-R125LW (Long Wheelbase), TT-R125LWE (Long Wheelbase Electric Start)
Estimated Page Count:
300-500 (typical for comprehensive service manuals of this era)
Type:
Service Repair Manual / Workshop Guide
Format:
Digital (likely PDF, as specified by availability)
Engine:
Engine disassembly, assembly, inspection, lubrication, cooling system, carburetor, fuel system, ignition system, exhaust system
Transmission:
Clutch, gearbox, shifting mechanism, lubrication
Chassis And Frame:
Frame inspection, steering system, front suspension, rear suspension (shock absorber, swingarm), wheels, spokes, hubs
Brakes:
Front and rear brake systems (likely drum brakes for this model), brake lever, cables, adjustments
Electrical System:
Wiring diagrams, battery, lighting (headlight, taillight), ignition system components, CDI unit, starter motor (for E/LWE models), fuses
Fuel System:
Fuel tank, fuel lines, carburetor (likely Mikuni VM series), fuel filter, petcock
Bodywork And Plastics:
Seat, fenders, fuel tank cover, side panels, graphics
Routine Maintenance:
Oil changes, air filter cleaning/replacement, spark plug inspection/replacement, chain adjustment, lubrication points
Troubleshooting:
Diagnostic charts for common problems, symptoms, and potential causes
Major Repairs:
Engine rebuilds, transmission overhauls, suspension component replacement
Carburetor Tuning:
Adjustment of idle speed, mixture, jetting recommendations
Electrical Diagnosis:
Testing of ignition system components, battery, starter circuit
Depth:
Comprehensive, covering complete disassembly, repair, and reassembly with detailed diagrams and specifications. Suitable for both home mechanics and professional technicians.
Engine Type:
Four-stroke, SOHC, 2-valve
Displacement:
124 cc (7.58 cu in)
Bore X Stroke:
54.0 mm x 54.5 mm (2.13 in x 2.15 in)
Cooling System:
Forced air-cooled
Horsepower:
Approx. 10-12 HP (estimated for the era and displacement)
Torque:
Approx. 7-8 lb-ft (estimated for the era and displacement)
Carburetor Model:
Mikuni VM20SS (likely)
Fuel Capacity:
1.2 Gallons (4.5 L)
Oil Type:
Yamalube 4 (or equivalent SAE 10W-30 API SG or higher, JASO MA)
Oil Capacity:
0.90 Liters (0.95 US qt) without filter change; 0.95 Liters (1.00 US qt) with filter change.
Transmission Type:
Constant-mesh 5-speed manual
Clutch Type:
Wet, multi-plate
Final Drive:
Chain drive, RK 428SB (or equivalent)
Transmission Oil Type:
Yamalube Gear Oil (or equivalent SAE 80 API GL-4)
Transmission Oil Capacity:
0.58 Liters (0.61 US qt)
Length:
71.1 in (1805 mm) for standard TT-R125; 76.9 in (1955 mm) for TT-R125LW
Height:
41.3 in (1050 mm) for standard TT-R125; 43.9 in (1115 mm) for TT-R125LW
Wheelbase:
49.2 in (1250 mm) for standard TT-R125; 52.4 in (1330 mm) for TT-R125LW
Ground Clearance:
10.0 in (255 mm) for standard TT-R125; 11.5 in (292 mm) for TT-R125LW
Dry Weight:
Approx. 174 lbs (79 kg) for TT-R125E; 170 lbs (77 kg) for TT-R125
Wet Weight:
Not officially specified, but typically around 185-190 lbs.
Seat Height:
30.7 in (780 mm) for standard TT-R125; 32.1 in (815 mm) for TT-R125LW
Safety Ratings:
N/A (Off-road motorcycles are not subject to the same crash testing as street vehicles).
Braking System:
Front and rear drum brakes. The manual covers adjustment and inspection of these.
Frame Construction:
Steel semi-double cradle frame for durability.
Lighting:
Headlight, taillight/stoplight. Manual includes wiring and bulb replacement.
Infotainment Systems:
N/A (Basic off-road motorcycle).
Driver Assistance Features:
N/A (Basic off-road motorcycle).
Connectivity Features:
N/A (Basic off-road motorcycle).
Ignition Type:
CDI (Capacitor Discharge Ignition)
Starter Type:
Kick starter (all models); Electric starter (TT-R125E, TT-R125LWE)
Engine Oil Change:
Every 1000 km (600 miles) or 6 months, whichever comes first, under normal use. More frequent changes recommended for hard riding/racing.
Air Filter Cleaning:
Every 500 km (300 miles) or more frequently in dusty conditions.
Spark Plug Inspection:
Every 1000 km (600 miles).
Chain Lubrication:
Every 500 km (300 miles) and after washing/riding in rain.
Valve Clearance Check:
Every 4000 km (2500 miles).
Engine Oil Spec:
SAE 10W-30 API SG or higher, JASO MA. (Yamalube 4 Recommended)
Transmission Oil Spec:
SAE 80 API GL-4 Gear Oil. (Yamalube Gear Oil Recommended)
Coolant Type:
N/A (Air-cooled engine)
Common Wear Items:
Clutch plates, brake shoes, chain and sprockets, carburetor jets due to fuel quality, wheel bearings.
Carburetor Cleaning:
Frequent cleaning of the Mikuni VM20SS carburetor may be required due to its small bore and susceptibility to dirt ingress or fuel deposits.
Suspension Seals:
Fork seal leaks can occur with aggressive riding or age, requiring replacement. Manual details fork oil changes and seal replacement.
Electric Starter Reliability:
On E/LWE models, starter motors and associated circuitry can be a point of failure if not properly maintained or if subjected to abuse. The manual covers troubleshooting these components.
Yamaha Legacy:
Yamaha Motor Corporation has a long and storied history in motorsports, renowned for innovation and performance in motorcycles, ATVs, and snowmobiles.
Tt-R Lineage:
The TT-R line has been Yamaha's dedicated off-road trail bike range, evolving from smaller displacements to cater to a growing youth and recreational market. The TT-R125 succeeded earlier models like the TT-R100 and XR100-based bikes.
Production Period:
The TT-R125 series was produced for many years, with significant updates occurring over time. The 2004 model represents a specific iteration within this successful lineage.
Model Recognition:
While not typically receiving 'awards' like cars, the TT-R125 series has consistently been recognized by riders and publications as a durable, user-friendly, and capable entry-level trail bike.
Industry Reputation:
Highly regarded for its reliability and ease of maintenance, making it a popular choice for families and new riders.
