🏷️ Basic Information Identification Make: Yamaha Model: YZ125 Model Years Covered: 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Vehicle Type: Off-road Motorcycle (Motocross) 👋 Introduction Market Position Segment: 2-stroke Motocross Motorcycle Competitive Analysis Competitors Era: Competed against models from Honda (CR125R), Suzuki (RM125), Kawasaki (KX125). Key Features Engine Type: High-performance liquid-cooled, reed-valve inducted, 2-stroke engine. Suspension Type: Advanced Kayaba (KYB) suspension components, including USD forks and a Monoshock rear. Chassis Design: Lightweight aluminum or steel frame optimized for motocross handling. Value Proposition Diy Maintenance Savings: Enables owners to save money by performing maintenance and repairs themselves, avoiding dealer labor costs. Professional Service Replication: Empowers users to perform repairs with the same quality and accuracy as a professional technician. 📋 Manual Details Coverage Areas Coverage Type: Workshop Service Manual Primary Audience: Mechanical Technicians Secondary Audience: Enthusiast Owners Page Count Page Count: 553 Manual Type Manual Type: Service Manual / Repair Manual Language Language: English Format Format: PDF Delivery Method: Electronic Download (Email) Printability Printable: Yes 📖 Manual Coverage Systems Covered Engine Mechanical: Complete disassembly, overhaul, and assembly of the 125cc two-stroke engine. Fuel System: Carburetor tuning, cleaning, rebuilding, fuel tank, fuel lines, and fuel pump (if applicable). Ignition System: CDI unit, spark plug, ignition coil, stator, and timing specifications. Lubrication System: Two-stroke oil injection system (if applicable), gear oil specifications, and lubrication points. Exhaust System: Exhaust pipe, silencer, and reed valve assembly. Transmission: Gearbox disassembly, inspection, repair, clutch assembly, and operation. Cooling System: Air-cooling system, fin cleaning, and inspection. Electrical System: Wiring diagrams, lighting (if applicable), switches, fuses, and battery (if applicable). Suspension Front: Front fork disassembly, seal replacement, oil levels, damping adjustments, and spring specifications. Suspension Rear: Monoshock rear suspension, linkage, shock absorber service, and adjustment. Brakes Front: Hydraulic disc brake system, caliper service, master cylinder, brake pads, and fluid specifications. Brakes Rear: Hydraulic disc brake system, caliper service, master cylinder, brake pads, and fluid specifications. Wheels And Tires: Wheel bearing inspection and replacement, spoke tensioning, tire pressure, and fitment. Frame And Bodywork: Frame inspection, seat, fenders, handlebars, and control levers. Procedures Included Routine Maintenance: Oil changes, chain lubrication and adjustment, air filter cleaning, spark plug replacement. Tune Ups: Carburetor adjustment, ignition timing checks, and general performance optimization. Troubleshooting: Diagnostic procedures for common starting, running, and performance issues. Disassembly And Assembly: Detailed step-by-step instructions for component removal and installation. Overhaul Procedures: Comprehensive instructions for rebuilding major engine components and assemblies. Inspection And Replacement: Guidelines for inspecting wear and tear on parts and recommending replacement. Special Tool Identification: References to and illustrations of specialized tools required for specific tasks. Technical Depth Depth Of Coverage: In-depth technical information suitable for professional mechanics and experienced enthusiasts. Safety Information: Emphasis on safety precautions, warnings (WARNING, CAUTION, NOTE), and proper usage of tools and equipment. Proprietary Components: Includes instructions for proprietary Yamaha components and refers to manufacturer instructions for any third-party parts. 📊 Manual Specifications File Format File Format: PDF File Type: Digital Document Print Quality Printability: High-resolution, printable pages. Binding Type Binding Type: Not Applicable (Digital File) Paper Type Paper Type: Not Applicable (Digital File) ⚙️ Engine Specifications Primary Engine Engine Type: Liquid-cooled, 2-stroke, reed-valve induction Displacement: 124cc Bore X Stroke: Approx. 54.0 mm x 54.5 mm (varies slightly by year, check manual for specifics) Compression Ratio: Varies by year, typically around 9.5:1 - 10.5:1 (check manual) Performance Horsepower: Approx. 35-40 HP (at crankshaft, varies by year and tuning) Torque: Not typically specified in typical marketing terms for this class of bike, but torque curve is key. Fuel System Carburetor Type: Mikuni VM Series (e.g., VM28 or VM30, size varies by year) Fuel Type: Unleaded gasoline, 91 octane or higher recommended. Oil Mixture: Premix (50:1 ratio with high-quality 2-stroke oil) or Auto-lube system (check manual for specific year). Engine Component Specs Spark Plug Type: NGK BR8ES or equivalent (check manual for exact specification) 🔧 Transmission Standard Transmission Type: Constant-mesh 6-speed sequential Features Clutch Type: Wet, multi-disc, cable-actuated Gear Ratios: Specific gear ratios are detailed within the manual. Transmission Oil Type: Yamaha motorcycle gear oil (e.g., Yamalube Gear Oil) or equivalent SAE 80W API GL-4. Transmission Oil Capacity Transmission Oil Capacity: Approx. 0.75 Liters (check manual for exact capacity and fill level). 📐 Dimensions Exterior Overall Length: Varies by year, typically around 2160-2175 mm (85.0-85.6 in) Overall Width: Varies by year, typically around 800-825 mm (31.5-32.5 in) Overall Height: Varies by year, typically around 1270-1290 mm (50.0-50.8 in) Weights Dry Weight: Approx. 94-97 kg (207-214 lbs) (varies by year) Wet Weight: Approx. 100-103 kg (220-227 lbs) (with all fluids, varies by year) Wheelbase Wheelbase: Varies by year, typically around 1440-1445 mm (56.7-56.9 in) Ground Clearance Ground Clearance: Varies by year, typically around 350-360 mm (13.8-14.2 in) Seat Height Seat Height: Varies by year, typically around 960-965 mm (37.8-38.0 in) 🛡️ Safety...