This manual covers the Yamaha XS650SF and XS650-2F models from 1979. The XS650 line, known for its robust engineering and classic styling, represents a significant era in motorcycle heritage. These parallel-twin motorcycles, powered by a 745cc air-cooled engine, offer a direct and engaging riding experience, making them a popular choice for enthusiasts and collectors alike. Their mechanical simplicity and enduring design have cemented their place in motorcycle history. This comprehensive Workshop Repair Service Manual provides detailed instructions for the repair and overhaul of all major systems, including the engine, transmission, fuel, ignition, lubrication, exhaust, electrical, brakes, and suspension. It covers routine maintenance, component removal and installation, disassembly and assembly procedures, troubleshooting, and the use of special tools. This resource is designed to assist both experienced technicians and DIY enthusiasts in maintaining and repairing their Yamaha XS650SF XS650-2F, ensuring optimal performance and longevity. 🏷️ 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...