Positioning:
Essential documentation for owners and mechanics of the 1979 Harley-Davidson FX Shovelhead, a significant model in Harley-Davidson's history, known for its iconic styling and V-twin performance.
Value Proposition:
Provides invaluable technical data that empowers owners to perform maintenance, repairs, and customizations with confidence, reducing reliance on expensive dealership service or less reliable aftermarket information.
Comparison:
Directly addresses the need for reliable, factory-level technical information that is often scarce for vintage motorcycles. Competes with unofficial guides and third-party repair manuals by offering presumed factory-authorized data in a convenient digital format.
Features:
Detailed diagrams, step-by-step instructions, diagnostic procedures, torque specifications, fluid types, and wiring schematics.
Engine:
Shovelhead OHV V-Twin, Engine Disassembly/Assembly, Cylinder Heads, Cylinders, Pistons, Crankshaft, Camshafts, Valve Train, Oil Pump, Carburetor (CV/Linkert), Ignition System (Points/Electronic), Exhaust System
Transmission:
4-Speed Constant Mesh, Transmission Disassembly/Assembly, Gearbox Internals, Clutch Assembly (Wet Multiplate), Primary Drive (Chain), Final Drive (Belt/Chain depending on FX model variant)
Chassis:
Frame (Dyna-Glide Style FX), Swingarm, Front Forks (Show-Worn or similar), Rear Shocks, Steering Head Bearings, Wheel Bearings, Brake System (Disc Front, Drum Rear typically), Electrical System (Wiring Diagrams, Lighting, Charging System, Battery)
Electrical System:
Complete wiring diagrams for 1979 models, charging system (generator/alternator, regulator), ignition system (points or electronic), lighting circuits, starter system, horn, and instrumentation.
Bodywork And Trim:
Information on fender removal/installation, fuel tank mounting, seat assembly, and other exterior components.
Maintenance:
Routine Service, Oil Changes, Filter Replacements, Spark Plug Service, Chain Adjustment, Brake Pad Replacement, Battery Maintenance
Repair:
Engine Rebuild, Transmission Overhaul, Carburetor Tuning, Ignition Timing, Clutch Adjustment/Replacement, Fork Seal Replacement, Brake System Overhaul, Electrical Component Testing and Replacement
Troubleshooting:
Diagnostic charts, symptom-based troubleshooting for engine, electrical, and chassis issues
Special Tools:
Lists and descriptions of specialized tools required for specific repair procedures.
Depth:
Comprehensive from basic owner maintenance to complete engine and transmission rebuilds, including electrical system diagnostics.
Diagnostic Procedures:
Detailed step-by-step diagnostic trees for common faults and malfunctions across all major systems.
File Quality:
High-resolution, clear text and diagrams, searchable content where applicable.
Searchability:
Likely searchable text-based PDF, allowing users to quickly find specific topics or keywords.
Printability:
Printable pages for workshop use.
Binding:
N/A (Digital PDF)
Type:
Harley-Davidson Shovelhead OHV V-Twin
Displacement Options:
Typically 74 cubic inches (1200cc) and potentially 80 cubic inches (1340cc) depending on specific FX sub-models and factory updates.
Engine Design:
Air-cooled, 45-degree V-twin configuration with overhead valves operated by pushrods.
Horsepower:
Estimated 60-70 HP (Varies by exact configuration and tuning)
Torque:
Estimated 70-80 ft-lbs (Varies by exact configuration and tuning)
Carburetor:
Typically a Keihin Butterfly (CV) or Linkert carburetor, specific model dependent.
Fuel Type:
Unleaded Gasoline (typically 87-91 octane recommended, manual will specify)
Type:
4-Speed Constant Mesh Manual Transmission
Variants:
N/A (Standard for FX model)
Clutch Type:
Wet, Multiplate Clutch
Primary Drive:
Enclosed Chain Drive
Final Drive:
Belt Drive or Chain Drive (FX models varied, check specific sub-model)
Gear Ratios:
Specific gear ratios for 1st through 4th gear and final drive are detailed in the manual for diagnostic and repair purposes.
Wheelbase:
Approx. 60.5 inches (Varies slightly by specific FX model)
Length:
Approx. 87-90 inches (Varies by specific FX model)
Dry Weight:
Approx. 500-550 lbs (Varies by specific FX model)
Gross Vehicle Weight Rating:
Not typically specified for motorcycles, but payload capacity is implied by frame strength.
Oil Change Interval:
Typically every 2,500-5,000 miles or annually, as specified in the manual. Often involves primary and engine oil changes.
Tune Up Interval:
Recommended at 5,000-10,000 mile intervals, covering ignition, carburation, and valve adjustments.
Engine Oil Type:
Viscosity typically SAE 20W-50 or SAE 50, often a motorcycle-specific mineral oil. Manual will specify exact Harley-Davidson or equivalent recommendation.
Transmission Oil Type:
Typically Harley-Davidson Formula + or equivalent 80W-90 GL-4 gear oil for the transmission and primary drive.
Primary Oil Type:
Same as transmission oil (Harley-Davidson Formula + or equivalent).
Brake Fluid Type:
DOT 4 or DOT 5 (depending on system compatibility, manual will specify).
Fork Oil Type:
Specific weight fork oil, typically SAE 10W or 20W, manual will specify.
Oil Capacity Engine:
Typically around 3 quarts (2.8 liters) for the engine, but the manual will provide exact capacity for oil changes and complete fills.
Oil Capacity Transmission:
Typically around 1 pint (0.5 liters) for the transmission/primary, with the manual specifying exact levels.
Shovelhead Common Problems:
Oil leaks (rocker boxes, base gaskets, crank seals), pushrod tube leaks, oil consumption, ignition timing sensitivity, carburetor tuning challenges, transmission shifting quirks.
Electrical Common Problems:
Aging wiring harnesses, rectifier/regulator issues, headlight/taillight failures.
Frame And Suspension Issues:
Wear in steering head bearings, worn fork bushings and seals, potential issues with rear shock absorber performance.
Parts Info:
While this is a service manual, it implies the existence and necessity of specific Harley-Davidson OEM or equivalent replacement parts, often referenced by part numbers within the text.
Legacy:
Harley-Davidson, established in 1903, has a long-standing reputation for producing iconic V-twin motorcycles with a distinctive American character.
Fx Series:
The FX series, introduced in the early 1970s, represented a more 'custom' styling and often featured the Shovelhead engine in a frame derived from the FL series but with the narrower front end typically associated with the XL Sportster models, creating a unique blend.
Shovelhead Era:
The Shovelhead engine itself was produced from 1966 to 1984, making the 1979 model a late-production variant within this significant engine family.
