🏷️ Basic Information Identification Make: Aprilia Model: RS 125 Year: 2003 Engine Type: Two-stroke, single-cylinder Codes Chassis Code: RP/RS 👋 Introduction Market Position Segment: Lightweight sportbike, often considered a gateway to supersport riding due to its performance and styling. Competitive Analysis Competitors: Yamaha YZF-R125 (later models), Honda CBR125R, Suzuki GSX-R125 (later models), Kawasaki Ninja 125 (later models), Cagiva Mito. Key Features Performance Focus: High-revving two-stroke engine, aggressive styling, capable chassis, lightweight handling. Target Audience: Enthusiast riders looking for a sporty 125cc experience, track day participants, those learning advanced riding techniques. 📋 Manual Details Coverage Areas Primary Coverage: Full Service, Repair, Maintenance, Rebuild, Refurbish, Restoration Page Count Estimated Pages: 300+ Manual Type Type: Full Service Repair Manual Language Language: English Format Format: Digital (Likely PDF, though not explicitly stated, common for this type) 📖 Manual Coverage Systems Covered Engine System: Detailed teardown, assembly, tuning, diagnosis of the Rotax 122 two-stroke engine, including cylinder, piston, crankshaft, bearings, reed valve assembly, exhaust system. Fuel System: Carburetor (likely Dell'Orto PHBH/PHVA) adjustment, cleaning, rebuilding, jetting, fuel pump, fuel lines, and tank maintenance. Cooling System: Radiator, coolant hoses, water pump, thermostat, bleeding procedures. Electrical System: Ignition system (CDI, spark plug, coil), lighting (headlight, taillight, indicators), battery, charging system (stator, rectifier/regulator), starter motor, wiring diagrams, fuse box, switches. Transmission System: Gearbox teardown, assembly, clutch operation (wet multi-plate), gear shift mechanism, lubrication, chain and sprockets maintenance. Brakes System: Front and rear disc brake systems, hydraulic fluid, brake pads, calipers, master cylinders, bleeding procedures, rotor inspection. Suspension System: Front telescopic forks (upside-down or conventional depending on variant), rear monoshock absorber, linkage, adjustment, maintenance, seal replacement. Chassis Frame: Frame inspection, alignment, headstock bearings, swingarm maintenance. Bodywork And Trim: Fairing removal and installation, seat, fuel tank, plastics, decals, lighting units. Wheels And Tires: Wheel bearing inspection and replacement, tire selection and mounting, wheel balancing. Procedures Included Routine Maintenance: Oil changes, filter replacements, spark plug checks, chain lubrication and adjustment, air filter cleaning/replacement, brake fluid checks. Troubleshooting: Diagnosing common starting issues, poor running, electrical faults, braking problems, suspension issues, guided by symptom-based diagnostics. Repair And Rebuild: Complete engine teardown and rebuild, gearbox rebuild, carburetor overhaul, suspension fork servicing, brake caliper rebuilding. Electrical Diagnosis: Using wiring diagrams to trace faults, testing components like CDI units, stator, rectifier, starter motor. Technical Depth Depth: Comprehensive, covering everything from basic maintenance checks to complete engine rebuilds and advanced electrical troubleshooting. Includes torque specifications, clearances, and detailed step-by-step instructions. 📊 Manual Specifications File Format Digital Format: PDF (assumed) Print Quality Quality: High-resolution, clear text and diagrams (assumed for digital product) Binding Type Binding: N/A (Digital) Paper Type Paper: N/A (Digital) ⚙️ Engine Specifications Primary Engine Engine Code: Rotax 122 (common variant for this era) Engine Type: Liquid-cooled, two-stroke, single-cylinder Bore X Stroke: 54 x 54.5 mm Displacement: 125 cc Compression Ratio: 12.5:1 (typical) Induction: Reed valve intake, Dell'Orto PHBH 28 or PHVA carburetor (specific model may vary) Ignition: Electronic CDI Performance Horsepower: Approx. 30-34 HP (restricted variants may have lower figures for licensing) Torque: Approx. 20-22 Nm (14.7-16.2 lb-ft) Fuel System Fuel Type: Unleaded gasoline (minimum 95 RON recommended) Oil Mixture: Automatic oil injection system (separate oil reservoir) 🔧 Transmission Standard Type: 6-speed manual sequential Features Clutch: Wet, multi-plate Final Drive: Chain drive (520 pitch, typical) 📐 Dimensions Exterior Length: Approx. 1950 mm (76.8 in) Width: Approx. 750 mm (29.5 in) Height: Approx. 1100 mm (43.3 in) Wheelbase: Approx. 1370 mm (53.9 in) Weights Dry Weight: Approx. 130 kg (286.6 lbs) Wet Weight: Approx. 147 kg (324 lbs) (with fluids) Cargo Storage: Minimal under-seat storage, typically for tool kit and documents. 🛡️ Safety Features Ratings Crash Testing: Not typically rated by independent agencies like NHTSA/Euro NCAP for motorcycles of this era/class. Active Features Braking System: Dual-disc front brakes, single-disc rear brake. Brembo calipers common on some variants. Passive Features Lighting: Halogen headlight, LED taillight and indicators (depending on variant). Chassis Design: Sturdy perimeter frame designed for stability and responsive handling. 💡 Technology Features Infotainment Display: Analog tachometer and speedometer, basic LCD display for odometer and trip meter. Driver Assistance ABS: ABS was not a standard or common option on the 2003 RS 125 model. 🔧 Maintenance Service Intervals Oil Change: Every 3,000-5,000 km (1,800-3,000 miles) or annually, whichever comes first. Check manual for exact intervals. Spark Plug Inspection: Every 3,000-6,000 km (1,800-3,700 miles). Chain Maintenance: Lubricate every 500-800 km (300-500 miles) and adjust tension as needed (typically 15-25mm slack). Brake Fluid Flush: Every 12-24 months. Fluid Specifications Engine Oil: Premix 2-stroke oil (e.g., Motul 710 2T, Castrol TTS) for automatic injection system. Use quality synthetic 2-stroke oil rated for high performance. Coolant: Ethylene glycol based coolant, 50/50 mix with distilled water. Check manual for specific type. Brake Fluid: DOT 4 hydraulic fluid. Transmission Oil: 75W/90 or 80W/90 gear oil (refer to manual for exact capacity and specification)....