Segment:
Entry-level to intermediate off-road/trail riding motorcycle.
Target Audience:
Beginner riders, youth riders, and recreational trail riders seeking a capable and user-friendly off-road machine.
Competitors 2002:
Honda CRF100F/CRF150F, Kawasaki KLX125/KLX140, Suzuki DR-Z125.
Engine Type:
Air-cooled, SOHC, four-stroke engine.
Suspension Features:
Long-travel suspension with adjustable front forks and a monoshock rear suspension (depending on LWE variant).
Frame Type:
Steel semi-double cradle frame.
Variants Distinction:
E (Electric Start), R (Kick Start), LWE (Long Wheelbase/Electric Start - often implying higher specification).
Engine:
Full engine overhaul, including carburetor, ignition system, lubrication, cooling (air-cooled), and top-end/bottom-end rebuild procedures.
Transmission:
Complete transmission system coverage, including clutch operation, gear shifting mechanisms, internal components, and lubrication.
Chassis:
Frame, subframe, suspension (front forks, rear shock absorber), steering system, and wheel assemblies.
Brakes:
Front and rear brake system inspection, maintenance, and repair, including hydraulic components, pads, and bleeding procedures.
Electrical:
Wiring diagrams, lighting system, battery, ignition system components, and troubleshooting electrical faults.
Fuel System:
Carburetor disassembly, cleaning, adjustment, and troubleshooting specific to the TT-R125 models.
Exhaust System:
Exhaust pipe and muffler inspection and maintenance.
Scheduled Maintenance:
Detailed recommended service intervals for oil changes, filter replacements, valve clearance checks, and general inspections.
Troubleshooting:
Comprehensive diagnostic flowcharts and symptom-based troubleshooting guides for common operational issues.
Engine Repair:
Step-by-step instructions for engine disassembly, component inspection, reassembly, and torque specifications.
Suspension Service:
Fork seal replacement, oil changes, and rear shock absorber adjustments.
Carburetor Tuning:
Jetting adjustments, idle speed settings, and mixture screw procedures.
Electrical Diagnostics:
Troubleshooting electrical circuits, testing components, and interpreting wiring diagrams.
Tire And Wheel Service:
Tire replacement, balancing, and wheel bearing maintenance.
Depth:
Expert-level technical details, suitable for professional technicians and experienced DIY enthusiasts. Covers everything from routine maintenance to complete engine and transmission rebuilds.
File Type:
PDF (Portable Document Format)
Searchability:
Likely text-searchable (depending on original scan quality), allowing for quick keyword lookup.
Quality:
Digital reproduction of original factory documentation. Quality is dependent on the source scan, but aims for clarity in diagrams and text.
Binding:
N/A (Digital PDF download)
Paper:
N/A (Digital PDF download)
Engine Type:
Four-stroke, SOHC, air-cooled
Displacement:
124 cc (7.57 cubic inches)
Bore X Stroke:
54.0 mm x 54.5 mm (2.13 in x 2.15 in)
Valve Train:
SOHC (Single Overhead Camshaft)
Horsepower Est:
Approx. 10-12 HP (exact figures often not publicly disclosed by Yamaha for off-road models)
Torque Est:
Approx. 6-8 lb-ft (exact figures not always disclosed)
Carburetor:
Mikuni VM20SS (or similar 20mm constant velocity carburetor)
Fuel Type:
Unleaded gasoline
Oil Type:
Yamalube 4 (or equivalent API SG, SAE 10W-40 motorcycle oil)
Ignition System:
CDI (Capacitor Discharge Ignition)
Length:
Approx. 1840 mm (72.4 in)
Width:
Approx. 780 mm (30.7 in)
Height:
Approx. 1115 mm (43.9 in)
Seat Height:
Approx. 790 mm (31.1 in)
Wheelbase:
Approx. 1270 mm (50.0 in) (Standard), Approx. 1335 mm (52.6 in) (LWE)
Wet Weight Est:
Approx. 94 kg (207 lbs) (E/R), Approx. 98 kg (216 lbs) (LWE)
Fuel Capacity:
6.1 Liters (1.6 US gal)
Rear Tire:
100/90-16M/C 54P
Safety Ratings:
N/A (Off-road motorcycles are not typically subjected to road-legal safety rating tests like NCAP).
Active Safety Features:
Reliable braking system, stable chassis design for off-road conditions.
Passive Safety Features:
Durable construction, designed to withstand off-road abuse. LWE variant may offer slightly more stability.
Engine Oil Change:
Every 1,000 km (600 miles) or 6 months, whichever comes first.
Air Filter Cleaning:
Every 1000 km (600 miles) or more frequently in dusty conditions.
Valve Clearance Check:
Every 4,000 km (2,500 miles)
Engine Oil Capacity:
0.95 Liters (1.0 US qt) when filter is not removed; 1.05 Liters (1.1 US qt) when filter is removed.
Engine Oil Specification:
SAE 10W-40 API SG (or equivalent motorcycle-specific oil)
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid
Common Wear Items:
Clutch plates, brake pads, tires, and carburetor jets due to off-road use and normal wear.
Carburetor Cleaning:
Carburetors can be prone to clogging if fuel is not fresh or if the bike sits for extended periods; regular cleaning is recommended.
Suspension Maintenance:
Fork seals can leak, and rear shock absorber may require servicing or replacement over time, especially with heavy use.
Brand Focus:
Yamaha has a long-standing reputation for producing high-performance motorcycles, including a strong presence in off-road and motocross disciplines since the 1960s.
Predecessors:
The TT-R series evolved from Yamaha's earlier trail and off-road models, focusing on user-friendliness and reliability for younger or less experienced riders.
Significance 2002:
The 2002 TT-R125 was a key player in the 125cc four-stroke trail bike segment, offering a balance of performance, ease of use, and Yamaha's renowned build quality.
Production Period:
The TT-R125 model line was produced for many years, with the 2002 model representing an early iteration of this popular platform.
