Basic Information Identification Make: Yamaha Model: R5C Year: 1972, 1973 Codes Chassis Code: R5C Introduction Market Position Category: Classic Japanese Sportbike Era: Early 1970s performance motorcycle Competitive Analysis Competitors 1972 1973: Kawasaki H1 Mach III, Suzuki T500 Titan, Honda CB750 Four (though larger capacity). Key Features Engine Type: Two-stroke, parallel-twin Performance Focus: Known for its sporty performance and handling relative to its displacement. Manual Details Coverage Areas Manual Type: Workshop Service Repair Manual Language: English Format: PDF Download Page Count Estimated Pages: Hundreds of pages (specific count not provided, but indicated as comprehensive) Manual Coverage Systems Covered Engine Mechanical: Complete disassembly, inspection, repair, and reassembly of the engine, including cylinder head, pistons, connecting rods, crankshaft, lubrication system, and cooling system. Fuel System: Carburetor overhaul, adjustment, fuel tank, fuel lines, and fuel pump (if applicable). Ignition System: Spark plugs, ignition coils, points, condenser, timing, and wiring diagrams. Transmission: Gearbox internal components, clutch operation, lubrication, and adjustments. Chassis And Frame: Frame inspection, reinforcement, and related components. Suspension: Front fork overhaul, rear shock absorbers, linkage, and adjustments. Brakes: Front and rear brake system inspection, adjustment, relining, and hydraulic components (if applicable). Electrical System: Wiring diagrams, lighting, battery, charging system, switches, and controls. Bodywork And Trim: Fairings, fuel tank, seat, fenders, and other body panels. Procedures Included Routine Maintenance: Oil changes, spark plug replacement, air filter cleaning/replacement, chain adjustment, brake adjustments, and general lubrication. Troubleshooting: Diagnosis of common problems, symptoms, and potential causes for engine, electrical, and mechanical issues. Rebuild Procedures: Detailed step-by-step instructions for overhauling major components like the engine and gearbox. Component Testing: Methods for testing and verifying the function of electrical components and mechanical parts. Technical Depth Depth: Comprehensive factory-level detail, suitable for professional mechanics and experienced enthusiasts. Covers everything from basic adjustments to full engine rebuilds. Manual Specifications File Format File Type: PDF Searchability: Likely searchable text within the PDF for easy navigation of specific topics. Print Quality Printable: Yes, designed to be printed entirely or in sections. Binding Type Binding: N/A (Digital PDF format) Paper Type Paper Quality: N/A (Digital PDF format, but original factory manuals were typically printed on durable paper) Engine Specifications Primary Engine Engine Type: 2-stroke, Air-cooled, Parallel-twin Displacement: 347 cc Bore X Stroke: 54.0 x 74.0 mm Compression Ratio: 6.7:1 Power Output: Approx. 33 HP @ 7,000 RPM (Manufacturer claimed, actual may vary) Torque: Approx. 23 lb-ft @ 6,500 RPM (Manufacturer claimed, actual may vary) Fuel System Carburetors: Dual Mikuni VM28SC Fuel Type: Unleaded gasoline (or leaded gasoline with appropriate octane rating for the era), mixed with 2-stroke oil. Lubrication System: Premix or Autolube system (check specific model variant). Transmission Standard Type: 5-speed Constant Mesh Clutch: Wet, multi-plate Features Final Drive: Chain drive Dimensions Exterior Length: Approx. 2,070 mm (81.5 in) Width: Approx. 760 mm (29.9 in) Height: Approx. 1,100 mm (43.3 in) Weights Dry Weight: Approx. 156 kg (344 lbs) Fuel Capacity: Approx. 16 L (4.2 US gal) Safety Features Ratings Crash Test Ratings: N/A (Motorcycle of this era did not have standardized crash testing as with modern cars). Active Features Braking System: Front: Disc brake; Rear: Drum brake. (Specific caliper and master cylinder details available in manual). Passive Features Lighting: Headlight, taillight, turn signals, brake light. Technology Features Infotainment System: N/A (Basic motorcycle technology of the era). Driver Assistance Features: N/A Connectivity Features: N/A Maintenance Service Intervals Oil Change: Refer to manual for specific mileage/time intervals. Typically every 2,000-3,000 miles or annually for gearbox oil. Spark Plug Replacement: Refer to manual for specific mileage. Typically every 3,000-5,000 miles depending on usage and plug type. Air Filter Cleaning: Refer to manual for specific mileage. Frequent cleaning recommended in dusty conditions. Fluid Specifications Engine Oil Type: Yamaha recommends specific 2-stroke engine oil. Refer to manual for grade and premix ratio. Gearbox Oil Type: Yamalube Gear Oil SAE 80 or equivalent API GL-4 transmission oil. Brake Fluid Type: DOT 3 or DOT 4 brake fluid (if hydraulic front brake). Known Issues Carburetor Sync: Carburetors can drift out of sync, requiring regular adjustment for smooth running. Ignition Points: Points and condensers require periodic cleaning and adjustment to maintain ignition timing. 2 Stroke Carbon Buildup: Common in 2-stroke engines, leading to fouled spark plugs and reduced performance; requires periodic de-carbonizing. Reed Valves: Wear or damage to reed valves can affect engine performance and starting. Manual covers inspection and replacement. Vehicle History Brand Heritage Yamaha Motorcycles: Yamaha has a long history in motorsports and road motorcycles, known for innovation and performance, particularly with their 2-stroke engines. Model Evolution R5 Series: The R5 series was an evolution of Yamaha's parallel-twin 2-stroke offerings, preceding models like the RD350. The R5C represented refinements over earlier R5 models. Production Production Years: 1972-1973 Manufacturing Location: Japan Awards & Recognition Recognitions Motorsports Heritage: While the R5C itself may not have specific 'awards,' Yamaha's parallel-twin 2-stroke...