🏷️ Basic Information Identification Make: Yamaha Model: XS400 Year: 1979 Type: Motorcycle Codes Model Code: XS400-E 👋 Introduction Market Position Target Audience: Professional Technicians and DIY Mechanics Competitive Analysis Value Proposition: Comprehensive repair information, instant download, cost savings over physical manuals Key Features Accessibility: Instant Download, No Shipping Costs Usability: Numbered Table of Contents, Bold Figure Numbers for easy referencing 📋 Manual Details Coverage Areas Scope: Full Service Repair Page Count Estimated Page Count: Varies (Typical for this era ~200-400 pages) Manual Type Type: Service and Repair Manual Language Language: English Format File Format: PDF 📖 Manual Coverage Systems Covered Engine: Complete overhaul, tuning, carburetor servicing, ignition system diagnosis Transmission: Clutch operation, gearbox maintenance, shifting mechanism Electrical: Wiring diagrams, charging system, lighting, ignition components, starter system Chassis: Frame inspection, suspension (front fork, rear shocks), steering system Brakes: Front and rear brake system maintenance, hydraulic components, adjustment Fuel System: Fuel tank, fuel lines, petcock, carburetor synchronization and adjustment Exhaust: Exhaust system inspection and servicing Wheels And Tires: Wheel bearing maintenance, tire pressure, wheel removal and installation Cooling System: Air intake and cooling fin cleaning procedures Bodywork: Seat removal, fuel tank mounting, fender inspection, side cover servicing Lubrication System: Oil pump servicing, oil filter replacement, oil gallery inspection Procedures Included Maintenance: Scheduled maintenance, lubrication, fluid changes, filter replacement Repair: Engine rebuild, transmission repair, electrical fault finding, suspension overhaul Troubleshooting: Diagnostic procedures for common and uncommon faults, electrical troubleshooting charts Rebuilding: Detailed instructions for component rebuilds (e.g., engine, carburetors, brake calipers) Refurbishment: Guidance on restoring components to original specifications Diagnostics: Electrical system diagnostics, performance troubleshooting Wiring Diagrams: Detailed, integrated with electrical troubleshooting Specifications: Torque specifications for all major fasteners, clearances, tolerances Service Schedules: Preventative maintenance schedules for various mileages and time intervals Technical Depth Level: Comprehensive (Professional Technician Level) Detail Level: Detailed sub-steps, notes, cautions, warnings, numbered instructions Illustrations: Detailed illustrations, drawings, photos, enlarged insets 📊 Manual Specifications File Format Compatibility: All versions of Windows & Mac Print Quality Printability: Full Printable (All pages) Binding Type Digital Binding: N/A (Digital Download) Paper Type Digital Storage: Savable to hard-drive, burnable to CD-ROM Requirements Software Requirements: Adobe PDF Reader & WinRAR ⚙️ Engine Specifications Primary Engine Configuration: Parallel-Twin, Four-Stroke Displacement: 392 cc (approx.) Bore X Stroke: 64.0 mm x 62.0 mm (typical for XS400 variants) Compression Ratio: 9.2:1 (typical) Cooling System: Air-cooled Valve Train: DOHC (Double Overhead Camshafts), 2 Valves per Cylinder Performance Horsepower: Approximately 27-30 HP (at crank) Torque: Approximately 22-24 lb-ft (at crank) Fuel System Carburetors: Dual Mikuni VM34 (or similar constant velocity carburetors) Fuel Delivery: Gravity feed from fuel tank via petcock Ignition Ignition Type: Electronic Ignition (CDI) Lubrication Oil Type: SAE 20W-40 or 10W-40 API SE classification motorcycle oil (refer to manual for precise recommendation) Oil Capacity: Approximately 2.2-2.5 liters (including filter change) 🔧 Transmission Standard Type: Constant Mesh, 5-Speed Sequential Features Clutch: Wet Multi-Plate Clutch Drive Type: Shaft Drive 📐 Dimensions Exterior Wheelbase: Approximately 55.5 inches (1410 mm) Weights Dry Weight: Approximately 370 lbs (168 kg) 🛡️ Safety Features Ratings Safety Standards: N/A (Era specific, emphasis on mechanical reliability) Active Features Braking System: Front: Disc Brake, Rear: Drum Brake Passive Features Lighting: Headlight, Tail Light, Turn Signals 💡 Technology Features Infotainment Features: N/A (Analog instrumentation: speedometer, tachometer, odometer, indicator lights) Driver Assistance Features: N/A (No electronic rider aids common in this era) 🔧 Maintenance Service Intervals Oil Change: Every 3,000 miles or 6 months (typical, refer to manual for specifics) Spark Plug Check: Every 6,000 miles (typical) Valve Clearance Check: Every 12,000 miles (typical) Fluid Specifications Brake Fluid: DOT 3 or DOT 4 (refer to manual for precise specification) Fork Oil: Typically SAE 10W fork oil, capacity approx. 180-190cc per fork leg (refer to manual) Known Issues Common Problems: Carburetor synchronization drift, electrical connector corrosion, worn output shaft seal, aging rubber components (hoses, mounts) 📚 Vehicle History Brand Heritage Manufacturer Origin: Japan Model Evolution Xs Series Context: Part of Yamaha's successful XS line, known for reliable parallel-twin engines Production Production Period: Late 1970s to early 1980s