The 1991 Sportster series represents a continuation of an iconic American motorcycle lineage, known for its distinctive air-cooled, 45-degree V-twin Evolution engine. Available in displacements such as 883cc and 1199cc, these models feature a robust steel frame and a reliable drivetrain, typically utilizing a belt or chain final drive. Designed for the cruiser and performance motorcycle segment, the Sportster offers a classic riding experience characterized by its unique V-twin rumble and customizable nature, appealing to riders who appreciate heritage and mechanical simplicity. This comprehensive service and workshop manual provides detailed information essential for the maintenance and repair of all 1991 Sportster models. It covers a wide array of systems, including engine overhaul, fuel and ignition systems, transmission and drivetrain, electrical systems, braking, suspension, and chassis components. The manual includes routine maintenance procedures, in-depth troubleshooting guides, technical specifications, torque values, and clearances, empowering owners, mechanics, and technicians to ensure the optimal performance and longevity of their Sportster. 🏷️ Basic Information Identification Make: Harley-Davidson Model: Sportster Year: 1991 Model Variant: All Sportster Models (e.g., XLH883, XLH1200) Codes Vin Code Vehicle Class: K (Motorcycle) 👋 Introduction Market Position Market Segment: Cruiser/Performance Motorcycle Target Audience: Enthusiast owners, independent mechanics, and dealerships performing maintenance and repairs. Competitive Analysis Competitors 1991: Other V-twin motorcycles from brands like Indian (limited presence), and Japanese offerings like the Yamaha Virago, Kawasaki Vulcan, and Honda Shadow in the cruiser segment. Key Features Vehicle Engine Architecture: Air-cooled, 45-degree V-twin OHV (pushrod) engine. Frame Design: Steel frame with integrated oil tank (on most models). Drive System: Enclosed primary drive with wet clutch, driving a 4-speed or 5-speed transmission, via final belt drive or chain drive (depending on specific model variant). 📋 Manual Details Coverage Areas Primary Coverage: Comprehensive service, repair, and maintenance for the 1991 Harley-Davidson Sportster series. Page Count Estimated Page Count: 300-500 (typical for this era of detailed service manuals) Manual Type Manual Type: Service Manual / Workshop Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Overhaul: Complete disassembly, inspection, repair, and reassembly of Evolution (Evo) engine components. Fuel System: Carburetor (e.g., Keihin CV) tuning, rebuilding, and troubleshooting; fuel lines, pump (if applicable), and tank maintenance. Ignition System: Ignition timing, coil testing, spark plug specifications, electronic control module (ECM) diagnostics (if applicable). Transmission Drivetrain: Gearbox service, clutch adjustment and replacement, primary drive system maintenance, belt drive inspection and tensioning. Electrical System: Wiring diagrams, battery maintenance, charging system (stator, regulator/rectifier), lighting, starter motor, and accessory circuits. Braking System: Front and rear brake caliper service, master cylinder maintenance, brake fluid replacement, rotor inspection, and pad replacement. Suspension Steering: Front fork service (oil change, seal replacement), rear shock absorber adjustment and replacement, steering head bearing maintenance. Wheel Tire: Wheel bearing inspection and replacement, tire pressure recommendations, wheel balancing, and spoke maintenance (if applicable). Exhaust System: Exhaust pipe and muffler inspection, gasket replacement, and heat shield maintenance. Frame Bodywork: Frame inspection for damage, body panel removal and installation, seat and fender maintenance. Procedures Included Routine Maintenance: Oil and filter changes, spark plug replacement, air filter cleaning/replacement, chain adjustment (if applicable). Troubleshooting: Diagnostic procedures for common starting, running, and electrical issues. Engine Rebuild: Detailed steps for top-end and bottom-end engine rebuilds, including piston, ring, and valve service. Transmission Repair: Gearbox disassembly and reassembly, bearing replacement, and shift mechanism repair. Electrical Diagnostics: Step-by-step troubleshooting for electrical system faults using wiring diagrams and test procedures. Carburetor Rebuild: Complete instructions for disassembling, cleaning, and reassembling the Keihin CV carburetor. Brake System Overhaul: Bleeding procedures, seal replacement, and component inspection for braking systems. Suspension Tuning: Instructions for adjusting and rebuilding front and rear suspension components. Technical Depth Depth Of Coverage: Comprehensive, covering from basic maintenance to full engine and transmission rebuilds. Diagnostic Information: Detailed diagnostic trees and symptom-based troubleshooting guides. Torque Specifications: Precise torque values for all critical fasteners and components. Clearances Tolerances: Specifications for engine component clearances, bearing tolerances, and other critical measurements. Wiring Diagrams: Detailed, color-coded electrical schematics for all systems. 📊 Manual Specifications File Format File Format: PDF (Portable Document Format) Searchability: Likely text-searchable if digitally generated, enabling quick information retrieval. Print Quality Print Quality: High-resolution, suitable for clear printing of text and diagrams. Binding Type Binding Type Digital: N/A (Digital format) Paper Type Paper Type Digital: N/A (Digital format, printable on any paper) ⚙️ Engine Specifications Primary Engine Engine Type: Harley-Davidson Evolution (Evo) V-twin Engine Displacement Cc: 883cc (for XLH883), 1199cc (for XLH1200) Bore Stroke 883Cc: 3.00 in. x 3.80 in. (76.2 mm x 96.8 mm) Bore Stroke 1200Cc: 3.50 in. x 3.80 in. (88.9 mm x 96.8 mm) Compression Ratio 883Cc: 8.4:1 Compression Ratio 1200Cc: 8.8:1 Performance Horsepower 883Cc Approx: 48-50 HP Horsepower 1200Cc Approx: 58-60 HP Torque Nm 883Cc Approx: 66 Nm @ 3200 RPM Torque Nm 1200Cc Approx: 84 Nm @ 3200 RPM Fuel System Carburetor...