🏷️ Basic Information Identification Make: Yamaha Model: XS650SF Model Variant: XS650-2F Year: 1979 Codes Model Code: XS650SF / XS650-2F 👋 Introduction Market Position Positioning: Essential resource for owners and technicians to maintain and repair the Yamaha XS650SF XS650-2F 1979. Competitive Analysis Value Proposition: Provides dealership-level information and procedures to enable professional-quality repairs, saving time and money. Key Features Accuracy Assurance: Endeavored to ensure accuracy, containing all necessary instructions for any repair. Purpose: To help owners get the best value from their vehicle by facilitating informed maintenance and repair. 📋 Manual Details Coverage Areas Primary Coverage: Repair and overhaul of Yamaha XS650SF XS650-2F 1979 models Additional Coverage: Proprietary component repair instructions Page Count Total Pages: 212 Manual Type Type: Workshop Repair Service Manual Language Language: English Format Delivery Format: PDF Download 📖 Manual Coverage Systems Covered Engine: Complete repair, disassembly, and assembly Transmission: Complete repair, disassembly, and assembly Fuel System: Repair and adjustment procedures Ignition System: Repair and adjustment procedures Lubrication System: Maintenance and repair Exhaust System: Maintenance and repair Electrical System: Comprehensive repair and troubleshooting Bodywork: Repair and maintenance Brakes: Repair and maintenance procedures for front and rear braking systems. Suspension: Front fork and rear shock absorber overhaul and adjustment. Wheels Tires: Information on wheel removal, tire mounting, and spoke tensioning. Frame Chassis: Inspection and maintenance of the frame and related components. Procedures Included Maintenance: Routine maintenance, tune-ups, lubrication Removal Installation: Component removal and installation procedures Assembly Disassembly: Detailed procedures for all major assemblies Troubleshooting: Diagnostic and repair procedures for common issues Special Tools: Identification and usage of specialized tools Engine Rebuild: Detailed step-by-step instructions for complete engine disassembly, inspection, and reassembly. Carburetor Rebuild: Instructions for disassembly, cleaning, and reassembly of Mikuni carburetors. Electrical Diagnostics: Troubleshooting charts and procedures for electrical system faults. Tune Up: Procedures for engine tuning, including ignition timing, carburetor synchronization, and idle speed adjustment. Technical Depth Depth: Comprehensive, from routine maintenance to complete engine and transmission overhauls Target Audience: Technicians conversant with general automobile practices, DIY enthusiasts 📊 Manual Specifications File Format Format: PDF Searchability: Likely text-searchable PDF, enhancing usability. File Size: Variable based on PDF compression, but typically manageable for email delivery. Print Quality Printability: Yes, printable Binding Type Binding: Digital (PDF Download) Paper Type Paper Type: Not Applicable (Digital) ⚙️ Engine Specifications Primary Engine Configuration: 745cc, Air-cooled, Four-stroke, Parallel-twin Bore X Stroke: 75.0 mm x 82.0 mm (Approximate, common XS650 spec) Compression Ratio: 8.5:1 (Typical for XS650 models) Performance Horsepower: Approx. 50 HP @ 6700 RPM (Varies by market/tuning) Torque: Approx. 42 ft-lbs @ 5000 RPM (Varies by market/tuning) Fuel System Carburetion: Dual Mikuni VM Series Carburetors (e.g., VM34) Fuel Type: Unleaded Gasoline (91 Octane or higher recommended) Lubrication System Type: Wet Sump Oil Capacity: Approx. 2.5 Liters (with filter change) Oil Recommendation: SAE 10W-40 or 10W-50 Motorcycle Engine Oil (API SE, SF or SG) 🔧 Transmission Standard Type: 5-Speed Constant Mesh Drive Type: Chain Drive Features Clutch Type: Wet, Multi-disc Transmission Oil Type: Yamaha Motorcycle Gear Oil or equivalent API GL-4 Transmission Oil Capacity: Approx. 1.0 Liter 💡 Technology Features Infotainment Features: No integrated infotainment system; relies on analog instrumentation. Driver Assistance Features: No driver-assistance features; purely mechanical operation. Connectivity Features: No modern connectivity features. 🔧 Maintenance Service Intervals Oil Change: Every 3,000 km or 6 months, whichever comes first Valve Clearance Check: Every 6,000 km or 12 months Spark Plug Replacement: Every 12,000 km or 12 months Fluid Specifications Engine Oil: SAE 10W-40 or 10W-50 Motorcycle Engine Oil (API SE, SF or SG) Transmission Oil: Yamaha Motorcycle Gear Oil or equivalent API GL-4 Brake Fluid: DOT 3 or DOT 4 Coolant: Not Applicable (Air-Cooled) Known Issues Common Wear Points: Cam chain tensioner, XS Performance exhaust leaks, electrical connections, front fork seals. Carburetor Tuning: Can be sensitive to tuning; requires precise synchronization and jetting for optimal performance. Charging System: Stator and regulator/rectifier can be prone to failure over time. Safety Precautions Torque Wrench Use: Essential for ensuring fasteners are tightened to specification, particularly cylinder head and crankcase bolts. Personal Protective Equipment: Recommended when working with fuels, oils, and during general repair tasks. 📚 Vehicle History Brand Heritage Heritage: Yamaha Motor Company, known for innovation and performance in motorcycles. Model Evolution Xs650 Lineage: The XS650 series, introduced in the early 1970s, was a highly influential parallel-twin motorcycle that gained a strong following for its robust engineering and classic styling. Production Production Era: 1970s - early 1980s (XS650 line)