This manual covers the FLHS, a model from 1981 belonging to the renowned Shovelhead generation. Known for its iconic V-twin engine and classic cruiser styling, the FLHS represents a significant piece of American motorcycle heritage. Engineered for the open road, this model is celebrated for its distinctive sound and robust construction, embodying the spirit of freedom and the open highway. Its design prioritizes rider experience and mechanical integrity, making it a beloved machine for enthusiasts and collectors alike. This factory service repair manual provides comprehensive guidance for the maintenance, repair, and troubleshooting of your FLHS. It includes detailed procedures for engine overhaul, transmission repair, and electrical diagnostics, complete with wiring diagrams. You will find step-by-step instructions for all scheduled services, carburetor and fuel system maintenance, suspension and brake system work, and extensive troubleshooting sections. With hundreds of pages, illustrations, and critical notes, this manual is an essential resource for do-it-yourself owners and professional mechanics seeking to keep their Shovelhead in optimal condition. 🏷️ Basic Information Identification Make: Harley-Davidson Model: FLHS Year: 1981 Generation Code: Shovelhead 👋 Introduction Market Position Target Audience: Do-it-yourself owners and experienced mechanics. Competitive Analysis Value Proposition: Inexpensive way to keep the vehicle working properly; saves on professional labor costs. Key Features Completeness: COMPLETE official full factory service repair manual. Accessibility: Immediate PDF download, no shipping or waiting. Usability: Printable pages for on-demand reference in the workshop. 📋 Manual Details Coverage Areas Engine Overhaul: Complete Transmission Repair: Complete Electrical Diagnostics: Comprehensive with Wiring Diagrams Chassis Systems: Suspension, Steering, Brakes Maintenance Procedures: All Scheduled Services Troubleshooting: Extensive Section Fuel System: Carburetor and Fuel Delivery Exhaust System: Included Page Count Estimated: Hundreds of Pages Manual Type Type: Factory Service Repair Manual Language Language: English Format File Format: PDF 📖 Manual Coverage Systems Covered Engine: Shovelhead V-Twin (Displacement details vary by specific FLHS sub-model, typically 74 cubic inch or 80 cubic inch variants). Clutch: Operation, Adjustment, and Repair Primary Drive: Chain Drive System Components and Maintenance Transmission: 4-Speed Gearbox (Operation, Disassembly, Reassembly) Kickstarter: Mechanism and Repair Fuel System: Carburetor Tuning (e.g., Keihin Butterfly or CV), Fuel Lines, Tank Exhaust Systems: Pipe Removal, Installation, and Sealing Electrical System: Ignition, Lighting, Charging System (Alternator/Generator), Starter, Battery Front Suspension: Fork Assembly (Telescopic), Seals, Oil Changes Steering: Headset Bearings and Adjustment Rear Suspension: Shock Absorbers and Swingarm Bearings Brakes: Front and Rear Brake System Overhaul, Fluid Replacement Procedures Included General Information: Vehicle Identification, Specifications, Torque Values Periodic Lubrication: Grease Points, Fluid Change Intervals Maintenance: Routine Checks and Adjustments Tune Up: Ignition Timing, Carburetor Adjustment, Valve Clearance Engine Rebuild: Piston, Rings, Bearings, Seals, Cylinder Head Transmission Overhaul: Gear Inspection, Bearing Replacement, Shafts Electrical Troubleshooting: Component Testing, Circuit Diagnosis Brake Bleeding: Procedure for Hydraulic and Mechanical Systems Fork Seal Replacement: Step-by-step Guide Carburetor Rebuild: Jetting, Float Adjustment, Diaphragms Wiring Diagram Interpretation: Detailed Diagrams for Component Identification Technical Depth Depth: Complete Factory-Level Repair and Rebuild Procedures Illustrations: Hundreds of Photos and Illustrations Instructions: Step-by-step, Numbered Instructions Critical Information: Notes, Cautions, and Warnings Included Diagnostic Focus: Emphasis on Diagnosing and Repairing Problems 📊 Manual Specifications File Format Format: PDF Compatibility: Windows and Mac Operating Systems Portability: Printable (Entire Manual or Specific Pages) Print Quality Resolution: Professional Quality Binding Type Type: Digital Download (Printable) Paper Type Type: Not Applicable (Digital PDF) Requirements Software: Adobe PDF Reader ⚙️ Engine Specifications Primary Engine Type: Shovelhead V-Twin, Air-Cooled Displacement: Typically 74 cu in (1213 cc) or 80 cu in (1310 cc) for this era, manual covers specific variant. Cylinder Arrangement: 90-degree V-Twin Performance Horsepower: Specifications within the manual are model-specific; typically around 50-60 HP for stock configurations. Torque: Specifications within the manual are model-specific; typically around 65-75 ft-lbs for stock configurations. Fuel System Carburetor: Commonly Keihin butterfly or Constant Velocity (CV) carburetors. Manual details adjustment and rebuild. Fuel Type: Unleaded gasoline (Manual will specify octane requirements). 🔧 Transmission Standard Type: 4-speed Constant Mesh Optional Type: Not applicable for this specific model year's primary transmission. Features Drive: Primary drive: Chain; Final drive: Belt or Chain (depending on specific FLHS configuration). 📐 Dimensions Exterior Wheelbase: Typically around 62.5 inches (1588 mm), but refer to manual for exact FLHS specification. Weights Dry Weight: Approximate range of 600-650 lbs (272-295 kg), manual will have precise figure. 💡 Technology Features Infotainment Features: Minimal by modern standards. Primarily focused on mechanical and electrical operation rather than digital interfaces. Driver Assistance Features: None by modern definition. Focus is on rider control of mechanical systems. Connectivity Features: N/A 🔧 Maintenance Service Intervals Oil Change: Typically every 2,000-3,000 miles or annually. Manual will specify precise intervals and procedures. Tune Up: Recommended every 5,000-7,500 miles for ignition timing, carburetor adjustments, and spark plug replacement. Fluid Specifications Engine Oil: Manual will specify SAE viscosity grade (e.g., 20W-50) and type (e.g., V-twin specific or mineral oil). Transmission Oil: Manual will specify type and viscosity...