🏷️ Basic Information

Make:

Yamaha

Model:

TTR125

Year:

2002

Engine Code:

Likely a 125cc 4-stroke OHV, specific code varies but often denoted by frame VIN

👋 Introduction

Market Position:

The Yamaha TTR125 is a popular entry-level to intermediate off-road (dirt bike) motorcycle, known for its user-friendliness, reliability, and suitability for trail riding and recreational use. The 2002 model represents a key year in its development.

Competitive Analysis:

Competes directly with other small-displacement off-road motorcycles from manufacturers like Honda (CRF150F), Kawasaki (KLX125), and Suzuki (DR-Z125). Its key strengths are its robust engine, accessible ergonomics, and Yamaha's reputation for quality.

Key Features:

User-friendly power delivery, capable suspension for trail riding, durable construction, and a relatively low seat height for rider confidence. Available in both kick-start and electric-start variants, though the 2002 model is predominantly kick-start.

📋 Manual Details

Coverage Areas:

Engine, Chassis, Electrical System, Suspension, Brakes, Fuel System, Lubrication, Cooling, Transmission, Troubleshooting, Maintenance, General Repair

Page Count:

Estimated 200-300 pages (based on typical service manuals for this class of motorcycle)

Manual Type:

Service Repair Workshop Manual

Completeness:

Full Factory Service Manual (FSM) equivalent

Language:

English

Format:

Downloadable PDF

📖 Manual Coverage

Systems Covered:

Engine Assembly/Disassembly, Carburetor Tuning and Overhaul, Ignition System Diagnostics, Electrical Wiring Diagrams, Clutch Operation and Adjustment, Transmission Gearbox Servicing, Suspension Fork and Shock Absorber Maintenance, Brake System Inspection and Repair, Fuel Tank and Petcock Servicing, Exhaust System Components, Frame and Bodywork Inspection, Wheel and Tire Maintenance, Chain Drive System Adjustment

Procedures Included:

Regular Maintenance Tasks, Oil Changes, Filter Replacement, Spark Plug Service, Valve Clearance Adjustment, Carburetor Cleaning and Synchronization, Brake Pad Replacement, Chain Lubrication and Adjustment, Tire Pressure Checks, Suspension Adjustment, Electrical Troubleshooting Guides, Engine Rebuild Procedures, Transmission Overhaul, Clutch Adjustment, Wheel Bearing Service, Torque Specifications for all fasteners

Technical Depth:

Comprehensive, covering everything from basic owner maintenance to full engine and transmission rebuilds. Includes detailed diagnostic procedures and schematics.

Diagnostic Tools:

While specialized electronic diagnostic tools are not used for this era of motorcycle, the manual covers standard diagnostic procedures using multimeters for electrical components and visual inspection for mechanical issues.

Troubleshooting:

Extensive section covering common performance issues, electrical faults, starting problems, and drivability concerns with systematic diagnostic trees.

📊 Manual Specifications

File Format:

PDF (Portable Document Format)

Print Quality:

High-resolution scans, clear illustrations and diagrams suitable for printing.

Binding Type:

N/A (Digital Download)

Paper Type:

N/A (Digital Download)

Searchable Text:

Yes, PDF format allows for text searching of keywords and topics.

Interactivity:

Hyperlinked Table of Contents and Index for easy navigation.

⚙️ Engine Specifications

Primary Engine:

124cc, Air-Cooled, Four-Stroke, SOHC, Single Cylinder

Horsepower:

Approximately 10-12 HP (est. at crankshaft)

Torque:

Approximately 7-8 lb-ft (est. at crankshaft)

Fuel System:

Carburetor (likely a Mikuni VM Series, specific size ~22mm)

Ignition:

CDI (Capacitor Discharge Ignition)

Lubrication:

Wet Sump

Bore X Stroke:

54.0 mm x 54.5 mm

Compression Ratio:

Approximately 9.5:1

Cooling System:

Air Cooled

Carburetor Model:

Likely Mikuni VM20SS or similar (specific designation crucial)

🔧 Transmission

Transmission:

5-Speed Constant Mesh

Optional:

N/A (standard transmission for the model)

Features:

Clutch operated by hand lever, reliable gearbox design for off-road use.

Clutch Type:

Wet, Multiple-disc

📐 Dimensions

Overall Length:

Approximately 1855 mm (73.0 in)

Overall Width:

Approximately 770 mm (30.3 in)

Overall Height:

Approximately 1085 mm (42.7 in)

Wheelbase:

1275 mm (50.2 in)

Ground Clearance:

Approximately 315 mm (12.4 in)

Front Tire Size:

80/100-21 51M

Rear Tire Size:

100/100-18 59M

Dry Weight:

Approximately 82 kg (181 lbs)

Fuel Capacity:

Approximately 5.5 Liters (1.45 US gal)

Seat Height:

Approximately 805 mm (31.7 in)

🛡️ Safety Features

Ratings:

N/A (Off-road motorcycles are not typically subject to DOT safety ratings).

Active Features:

Responsive braking system, predictable handling characteristics.

Passive Features:

Sturdy frame, impact-absorbing suspension.

💡 Technology Features

Infotainment:

N/A (Basic off-road motorcycle with no infotainment features)

🔧 Maintenance

Service Intervals:

Initial break-in service (around 600 miles/1000 km), then regular checks every 3 months or 2000 miles (3000 km). Specific intervals for oil changes (e.g., every 1000 miles/1600 km or annually), air filter cleaning/replacement, spark plug checks, and chain lubrication detailed in manual.

Engine Oil Type:

Yamalube 4 (or equivalent motorcycle specific 4-stroke oil), SAE 10W-40 or 20W-40 recommended. API service SG or higher.

Engine Oil Capacity:

Approximately 1.0 Liter (1.1 US qt) without filter change, 1.1 Liter (1.2 US qt) with filter change.

Brake Fluid:

DOT 3 or DOT 4 brake fluid (check reservoir cap for specific recommendation)

Known Issues:

Potential carburetor jetting issues if not properly maintained, chain wear, occasional clutch plate wear with heavy use. Manual will cover diagnosis and repair for these and more.

Air Filter Part Number:

Likely 5FC-14451-00-00 (verify with VIN and manual)

Oil Filter Part Number:

N/A (This model uses a screen/mesh type oil filter for the wet clutch system, not a disposable cartridge filter)

Recommended Spark Plug:

NGK CR9E or similar (verify in manual)

Valve Clearance Intake:

0.05 - 0.10 mm (Cold)

Valve Clearance Exhaust:

0.05 - 0.10 mm (Cold)

Chain Lubrication Interval:

Every 500 km (300 miles) or after riding in wet conditions.

📚 Vehicle History

Brand Heritage:

Yamaha Motor Company, Ltd. has a long and distinguished history in motorcycle manufacturing, known for innovation, performance, and reliability across various racing disciplines and street models.

Model Evolution:

The TTR line was introduced as Yamaha's durable and user-friendly off-road platform. The TTR125 specifically evolved from earlier Yamaha trail bikes, offering a balance of performance and ease of use for a wide range of riders. Subsequent models saw minor updates and variations like the TTR125L (long travel suspension/larger wheels).

Production:

The TTR125 was in production for many years, with the 2002 model being part of the initial generation of this specific platform.

Model Variants:

TTR125 (standard suspension), TTR125L (Long travel suspension, taller seat, larger front wheel for improved off-road capability). This manual likely covers both, or has specific sections.

Development Focus:

Designed for ease of maintenance and reliable trail performance, making it ideal for younger riders or casual off-road enthusiasts.

🏆 Awards & Recognition

Recognitions:

While not typically receiving formal 'awards' in the automotive sense, the TTR125 line has consistently received positive reviews from riders and industry publications for its segment. It's often cited as a benchmark for beginner-friendly off-road bikes.

Ratings:

User ratings often highlight its reliability and ease of maintenance.