🏷️ Basic Information Identification Make: Harley-Davidson Model: EL "Knucklehead" Years Covered: 1940-1947 Sub Model Designations: All Styles Covered Codes Engine Code Family: F-Head (referring to valve arrangement) 👋 Introduction Market Position Category: Classic Motorcycle Restoration and Maintenance Guide Competitive Analysis Value Proposition: An indispensable resource for owners and mechanics to maintain, repair, and restore iconic Harley-Davidson Knucklehead motorcycles, offering significant cost savings over professional shop labor. Key Features Completeness: Comprehensive official full factory service repair manual, covering all styles. Accessibility: Instant PDF download eliminates shipping wait times and costs. Usability: Printable pages allow for on-the-bench use or targeted information retrieval. 📋 Manual Details Coverage Areas Primary Coverage: Service, Repair, Maintenance, Troubleshooting Specific Models: 1940, 1941, 1942, 1943, 1944, 1945, 1946, 1947 Harley-Davidson EL Knucklehead Page Count Estimated Page Count: Hundreds of Pages (as indicated in product description) Manual Type Type: Factory Service Repair Manual / Workshop Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Mechanical: Engine assembly, disassembly, overhaul, internal components, cylinder head, cylinders, pistons, connecting rods, crankshaft, camshaft, timing. Fuel System: Carburetor service, fuel tank, fuel lines, fuel pump (if applicable to specific models within the range). Cooling System: Air cooling system management, fin inspection, heat dissipation. Lubrication System: Oil pump, oil lines, oil tank, lubrication system maintenance and troubleshooting. Clutch: Clutch operation, adjustment, service, and replacement of components. Transmission: Gearbox disassembly, assembly, maintenance, shifting mechanisms, gear ratios (likely 4-speed). Drive System: Primary drive system (chain or belt), clutch to transmission, secondary drive (chain or belt drive to rear wheel). Wheels Tires: Wheel bearing service, tire inspection and replacement, spoke maintenance, rim specifications. Brakes: Brake system inspection, adjustment, service (likely drum brakes), brake lining replacement. Suspension: Front fork service (likely springer fork), rear suspension components (if applicable, e.g., rigid frame with spring seat post). Steering: Steering head bearing service, handlebar components, control cables. Frame: Frame inspection, alignment, component mounting. Electrical System: Ignition system, lighting, battery, wiring, generator/alternator (depending on specific year evolution). Wiring Diagrams: Comprehensive wiring diagrams for electrical system troubleshooting. Procedures Included Maintenance Tasks: Regular maintenance checks, lubrication schedules, fluid changes, filter replacements, ignition timing adjustments, carburetor adjustments, brake adjustments. Repair Procedures: Step-by-step instructions for component repair and replacement, including detailed disassembly and reassembly of major systems. Troubleshooting: Diagnostic procedures for identifying and resolving common issues across all vehicle systems. Engine Rebuild: Complete engine disassembly, inspection, repair, and reassembly procedures. Electrical Diagnosis: Detailed troubleshooting of electrical faults using wiring diagrams and component testing. Technical Depth Depth: Complete factory-level detail, suitable for both novice and experienced mechanics, covering complete disassembly and rebuild. Illustrations: Hundreds of photos and illustrations guiding through procedures, with enlarged inset views for detailed parts examination. Instruction Style: Numbered instructions, detailed substeps, notes, cautions, and warnings. 📊 Manual Specifications File Format Format: PDF Compatibility: Works under all PC-based Windows operating systems and Mac. Print Quality Printability: Printable in its entirety or select pages without restriction. Digital Features: Can be saved to hard-drive and burned to CD-ROM. Binding Type Binding: Digital Download (no physical binding). Paper Type Paper Type: N/A (Digital) Requirements Software Requirements: Adobe PDF Reader ⚙️ Engine Specifications Primary Engine Engine Type: 45-degree V-Twin, Overhead Valve (OHV) - known as 'Knucklehead' due to rocker box shape. Engine Displacement: 61 cubic inches (1000cc) for EL models, 74 cubic inches (1200cc) for FL models (though this manual specifically lists 'Knucklehead' which typically refers to the EL). Bore X Stroke: EL: 3.3125 in x 3.5 in (84.14 mm x 88.9 mm) Compression Ratio: Typically 6.0:1 or higher, varying by model year and factory tuning. Performance Horsepower: Approximately 24-30 HP (estimated, specific figures vary by year and tune). Torque: Figures not readily available in general specifications, but torque delivery is characterized by strong low-end grunt. Fuel System Carburetor: Typically Linkert or Schebler carburetors (specific models and sizes vary by year). Fuel Type: Gasoline (likely leaded, with appropriate octane ratings for the era). 🔧 Transmission Standard Type: 4-speed constant mesh, manual foot shift with hand clutch operation (early models might have had different configurations). Optional Type: N/A for this specific model range. Features Clutch Type: Wet multi-plate clutch. Primary Drive: Chain drive (often primary chain in a sealed primary case). Secondary Drive: Chain drive to rear wheel. 📐 Dimensions Exterior Wheelbase: Approximately 57 inches (1448 mm) for EL models. Weights Dry Weight: Approximately 500-550 lbs (227-250 kg). 🛡️ Safety Features Ratings Safety Standards: Reflects safety standards of the era; modern safety features absent. Active Features Braking System: Drum brakes front and rear. Manual adjustment required. Passive Features Frame Construction: Robust steel frame, typically rigid rear (no suspension), with spring-mounted seat for rider comfort. 💡 Technology Features Infotainment Features: N/A (pre-infotainment era). Focus on mechanical and electrical systems. Driver Assistance Features: N/A. Basic lighting and ignition are the primary electrical functions. Connectivity Features: N/A. Mechanical...