Target Audience:
Harley-Davidson owners, mechanics, restorers, and enthusiasts of the 1973 FL Shovelhead model.
Value Proposition:
Provides authentic, factory-level technical information essential for maintaining and repairing a classic Harley-Davidson.
Authenticity:
Official factory manual, ensuring accuracy and adherence to original specifications.
Completeness:
Covers all major systems for a holistic approach to motorcycle service and repair.
Diagnostic Tool:
Crucial for accurate troubleshooting, saving time and reducing incorrect part replacements.
Engine:
Full engine disassembly, assembly, tuning, and troubleshooting for the Shovelhead V-twin engine.
Transmission:
Covers the 4-speed transmission, including clutch, gearbox, primary drive, and final drive.
Electrical System:
Wiring diagrams, ignition system, lighting, charging system (generator/alternator), and starter motor.
Chassis And Suspension:
Frame, front fork (often Hydra-Glide or similar), rear suspension components, and wheels.
Fuel System:
Carburetor (likely Linkert or Keihin), fuel tank, fuel lines, and fuel pump (if applicable).
Braking System:
Front and rear brake systems, including hydraulic and mechanical components.
Bodywork:
Fenders, fuel tank, seat, handlebars, and other cosmetic and structural body components.
Routine Maintenance:
Oil changes, filter replacements, spark plug service, chain adjustment, and lubrication.
Troubleshooting:
Diagnostic procedures for common and uncommon issues across all major systems.
Rebuild Procedures:
Detailed, step-by-step instructions for complete engine, transmission, and carburetor overhauls.
Calibration And Adjustment:
Carburetor tuning, ignition timing, clutch adjustment, and brake bleeding procedures.
Wiring Diagrams:
Comprehensive electrical schematics for diagnosing and repairing electrical faults.
Depth Level:
Comprehensive Factory Level
Diagnostic Capabilities:
Advanced diagnostics including internal component wear assessment and performance tuning.
Reconstruction Guide:
Suitable for full motorcycle restoration and complete engine rebuilds.
Searchability:
Likely text-searchable if properly scanned, enhancing usability.
Printability:
Designed for printing, allowing for a physical copy of the manual.
Suggested Binding:
Coil-bound or ring-bound for lay-flat usability in a workshop environment.
Recommended Paper:
Durable, heavier weight paper for workshop conditions.
Engine Type:
Air-cooled, 45-degree V-twin
Displacement:
74 cubic inches (1213 cc)
Bore X Stroke:
3.4375 in x 4.25 in (87.31 mm x 107.95 mm) (typical for 74ci)
Compression Ratio:
Approximately 7.0:1 to 7.5:1 (varies by specific setup)
Cylinder Heads:
Cast iron cylinders with aluminum alloy heads
Horsepower:
Estimated 50-60 HP (at crank, varies significantly with tuning and exhaust)
Torque:
Estimated 70-80 ft-lbs (at crank, varies significantly with tuning and exhaust)
Carburetor:
Likely a Linkert M-series or early Keihin butterfly carburetor (specific model depends on exact build)
Fuel Type:
Leaded or Unleaded gasoline (manual will specify recommendations for original tuning).
Ignition Type:
Contact breaker points ignition with a single coil.
Oil System:
Dry sump system with a separate oil tank.
Oil Type:
High-quality motorcycle-specific oil, often a straight-weight mineral oil (e.g., SAE 50 or 60 for older Shovelheads, manual will confirm).
Oil Capacity:
Approximately 3 quarts (2.8 liters) including oil tank (check manual for precise amount).
Transmission Type:
4-speed constant mesh, foot shift with hand clutch operation.
Gear Ratios:
Specific ratios will be detailed in the manual. Typically provides a strong low-end and usable top-end.
Clutch Type:
Wet multi-plate clutch.
Primary Drive:
Chain drive from engine crankshaft to transmission input shaft, enclosed in a primary chaincase.
Transmission Oil Type:
Manual will specify the correct gear oil for the transmission. Often a specific viscosity gear oil or even engine oil was used depending on the era and specific components.
Wheelbase:
Approximately 61-63 inches (155-160 cm), depending on specific FL model configuration (e.g., FLH).
Length:
Around 90-95 inches (228-241 cm).
Dry Weight:
Approximately 550-600 lbs (250-272 kg), depending on trim and accessories.
Fuel Capacity:
Typically 4.0 US gallons (15.1 liters) for the main tank. Some models might have had additional tanks or larger options.
Safety Standards:
Motorcycle safety standards of the early 1970s apply. No modern crash ratings.
Braking System Type:
Front: Often a hydraulic disc brake. Rear: Typically a drum brake.
Lighting:
Headlight, tail light, brake light, turn signals (often optional or dealer-installed in this era).
Frame Construction:
Steel tube frame, designed for stability and handling typical of the era.
Oil Change Interval:
Typically every 1,000-2,000 miles or seasonally, depending on usage (refer to manual for exact spec).
Primary Chain Tension:
Regular checks and adjustment are critical, often recommended every few thousand miles.
Spark Plug Replacement:
Typically every 3,000-6,000 miles, depending on plug type and usage.
Carburetor Adjustment:
As needed for optimal performance and idle, especially after long storage or major servicing.
Engine Oil:
SAE 50 or SAE 60 Motorcycle-specific mineral oil (e.g., Harley-Davidson's own oil or equivalent from brands like Valvoline, Spectro).
Transmission Oil:
Manual will specify. Could be a gear oil (e.g., SAE 75W-90 or 80W-90) or a specific ATF for some older configurations. Needs careful verification.
Primary Chaincase Oil:
Typically engine oil is used in the primary chaincase, but manual will confirm quantity and type.
Oil Leaks:
Common on Shovelheads due to age and seal materials. Manual covers seal replacement and gasket maintenance.
Carburetor Tuning:
Linkert carburetors require specific knowledge for proper tuning; Keihin also needs periodic adjustment. Manual provides detailed guidance.
Valve Adjustment:
Rocker arm and valve train adjustments are crucial for engine health and performance.
Primary Chain Stretch:
Requires regular inspection and tension adjustment to prevent damage to the primary drive and transmission.
Harley Davidson Legacy:
Harley-Davidson has a long-standing reputation for building large displacement V-twin motorcycles, synonymous with American cruising culture.
Shovelhead Introduction:
The Shovelhead engine replaced the Panhead engine in 1966 and remained in production until 1984. The 1973 model represents a mature iteration of this iconic engine design.
Fl Designation:
The 'FL' designation generally indicated a larger displacement model, with the 'H' in FLH often signifying a 'High Performance' or 'Highway' model, typically with a higher compression ratio and dual exhaust.
Manufacturing Era:
1966-1984
Key Changes 1973:
Specific changes for 1973 included updates to the electrical system, potentially frame modifications for improved handling, and refinements to the Shovelhead engine.