🏷️ Basic Information Identification Make: Derbi Model: GPR125 Model Variants: GPR125 R, GPR125 Racing Codes Engine Code Prefix Potential: D50B0 (common for Derbi 125cc, specific to model may vary) 👋 Introduction Market Position Target Audience: Derbi GPR125 R and GPR125 Racing owners, independent motorcycle workshops, and enthusiasts seeking in-depth technical knowledge. Competitive Analysis Value Proposition: Provides factory-level technical information and parts identification, crucial for maintaining and repairing these performance-oriented 125cc sportbikes. Key Features Documentation Type: Official factory documentation, ensuring accuracy and completeness. Illustration Density: Hundreds of illustrations and detailed wiring diagrams enhance understanding of complex procedures. Dual Coverage: Combines detailed service/repair information with a comprehensive parts catalogue for a holistic approach to ownership. 📋 Manual Details Coverage Areas Primary Manual Type: Service and Repair Manual Secondary Manual Type: Parts Catalogue Page Count Total Pages: OVER 250 Language Language: English Format File Format: PDF Delivery Format: ZIP 📖 Manual Coverage Systems Covered Engine Mechanical: Complete disassembly, inspection, assembly, torque specifications, piston, cylinder, crankshaft, connecting rod, valve train, timing. Engine Fuel System: Carburetor (type, jetting, adjustment), fuel pump, fuel lines, fuel tank. Cooling System: Radiator, water pump, thermostat, coolant specifications, bleeding procedures. Exhaust System: Muffler, catalytic converter (if applicable), exhaust manifold, mounting. Transmission Gearbox: Gearbox disassembly, inspection, assembly, shift mechanism, gear ratios, lubrication. Clutch System: Clutch type (e.g., wet multi-plate), clutch plates, springs, pressure plate, adjustment, operation. Electrical System: Wiring diagrams (comprehensive), battery, charging system (alternator/stator, regulator/rectifier), ignition system (CDI, spark plug), lighting (headlight, taillight, indicators), starter motor, horn. Chassis Frame: Frame inspection, steering head bearing, alignment. Suspension Front: Telescopic forks, oil specifications, seal replacement, spring rates, damping adjustments, fork rebuild. Suspension Rear: Monoshock absorber, linkage system, spring preload adjustment, damping settings, shock absorber rebuild. Braking System Front: Disc brake, caliper assembly, brake pads, master cylinder, brake lines, bleeding procedure, rotor specifications. Braking System Rear: Disc brake, caliper assembly, brake pads, master cylinder, brake lines, bleeding procedure, rotor specifications. Wheels Tires: Wheel bearing inspection and replacement, tire pressure, recommended tire sizes, wheel alignment. Bodywork Fairings: Fairing removal and installation, panel fasteners, seat, fuel tank mounting. Controls Cables: Throttle cable, clutch cable, brake lever adjustment, handlebar setup. Instrumentation Gauges: Speedometer, tachometer, indicator lights, wiring. Procedures Included Scheduled Maintenance: Oil change intervals, filter replacement, spark plug service, chain adjustment, general inspection checklists. Troubleshooting: Diagnostic charts for common issues related to engine performance, electrical faults, starting problems, braking, etc. Disassembly Reassembly: Step-by-step instructions with illustrations for complete component removal and installation. Engine Rebuild: Detailed procedures for top-end and bottom-end engine rebuilds, including component measurements and clearances. Electrical Diagnostics: Procedures for testing components, tracing circuits using wiring diagrams, and diagnosing electrical issues. Suspension Service: Fork seal replacement, shock absorber servicing, linkage lubrication. Brake System Service: Brake pad replacement, caliper servicing, master cylinder overhaul, brake fluid bleeding. Parts Identification: Exploded views of all major assemblies with corresponding part numbers for easy identification and ordering. Technical Depth Depth Level: Comprehensive: Covers everything from basic maintenance and adjustments to full engine and chassis overhauls. Diagnostic Capabilities: Advanced troubleshooting guides and diagnostic procedures for pinpointing and resolving complex issues. Performance Tuning: Information on carburetor tuning, potential performance modifications (within factory scope). 📊 Manual Specifications File Format File Type: PDF (Portable Document Format) Searchability: Likely searchable text within PDF, facilitating quick access to information. Print Quality Printability: Fully printable, allowing for physical copies for workshop use. Image Quality: Good quality illustrations and diagrams for clarity. Binding Type Digital Organization: Bookmarked PDF for easy navigation between sections. Paper Type Physical Medium Equivalent: Professional workshop manual paper quality (implied by 'good quality & fully printable'). ⚙️ Engine Specifications Primary Engine Engine Type: Two-stroke, single-cylinder (typical for Derbi GPR125, may vary slightly by year/market). Displacement: 125 cc (approximate, specific bore/stroke data in manual) Cooling Method: Liquid-cooled Bore X Stroke: Detailed specifications available in manual (e.g., typical 54mm x 54.5mm for D50B0). Performance Horsepower: Varies by market and restriction (e.g., ~15 HP for A1 license, higher for unrestricted racing versions). Torque: Specific figures available in manual, crucial for clutch setup. Fuel System Carburetor Type: Likely Dell'Orto PHVA or similar 28mm, with specific jetting details provided. Fuel Type: Unleaded gasoline (RON 95 or higher recommended). Fuel Mixture: Automatic oil injection system for two-stroke oil. 🔧 Transmission Standard Type: 6-speed constant mesh Optional Variants: Not applicable for factory standard models. Features Gear Ratios: Specific ratios for each gear and final drive provided in the manual. Clutch Type: Wet, multi-plate Transmission Oil Type: Specific API GL-4 or GL-5 gear oil recommendation in manual (e.g., SAE 75W/90 or 80W). 📐 Dimensions Exterior Wheelbase: Detailed specifications in manual (e.g., approx. 1330mm). Length: Detailed specifications in manual. Width: Detailed specifications in manual. Height: Detailed specifications in manual. Weights Dry Weight: Approx. 130-135 kg (varies by specific GPR125 variant). Fuel Tank Capacity: Approx. 13 liters. Oil Tank Capacity: Specific capacity for two-stroke...