Vehicle Class:
Cruiser / Custom Motorcycle
Target Audience Manual:
Harley-Davidson owners, independent motorcycle mechanics, vintage motorcycle restorers
Era Competitors:
Other American V-twin manufacturers (e.g., Indian, custom builders), and increasingly, Japanese manufacturers offering larger displacement models.
Motorcycle Appeal:
Iconic V-twin engine, classic styling, rider customization potential, association with American heritage.
Manual Value Proposition:
Provides the definitive factory information for maintaining and repairing a specific model of a highly sought-after vintage motorcycle.
Engine Systems:
Engine disassembly, assembly, overhaul, troubleshooting, lubrication, cooling system (air-cooled), ignition system, fuel system (carburetion), exhaust system
Transmission Drivetrain:
4-speed transmission (primary and secondary drive), clutch, final drive, gearbox overhaul, troubleshooting
Chassis Suspension Steering:
Frame, front suspension (forks, steering head bearings), rear suspension (shocks, swingarm), wheel bearings, steering mechanism
Brakes:
Front and rear brake systems (typically disc and drum configurations for this era), hydraulic systems, caliper and master cylinder overhaul, bleeding procedures
Electrical System:
Wiring diagrams, charging system (alternator, regulator), ignition system (points, coil, spark plugs), lighting, starting system (starter motor, solenoid), battery, instrumentation
Bodywork Fittings:
Fuel tank, fenders, seat, handlebars, controls, exhaust pipes, basic body panel removal and installation
Maintenance Procedures:
Regular servicing, oil changes, filter replacements, spark plug replacement, chain adjustment, brake adjustments, lubrication points
Repair Procedures:
Detailed step-by-step instructions for component overhaul and replacement (e.g., engine rebuild, transmission repair, brake caliper rebuild, fork seal replacement)
Troubleshooting Diagnostics:
Systematic diagnosis of common and uncommon problems, symptom-based troubleshooting charts, electrical diagnostic procedures
Special Tools:
Identification and usage of specialized Harley-Davidson tools required for specific procedures
Depth Of Information:
Factory-level detail, suitable for professional technicians and experienced enthusiasts; covers complete teardown and reassembly.
Digital File Format:
PDF (if digital), typically searchable and printable
Print Quality Original:
Good to excellent, with clear diagrams and text on durable paper
Binding Type Original:
Stapled, perfect bound, or wire-o bound depending on original factory specification
Paper Type Original:
High-quality, durable paper to withstand shop use
Engine Type:
Air-cooled, 45-degree V-twin, overhead valve (OHV)
Bore X Stroke Mm:
3.4375 in x 4.25 in (87.3 mm x 108 mm) - Typical for Shovelhead 80ci
Compression Ratio:
Approximately 8.0:1 (can vary slightly)
Engine Displacement Ci:
80 cubic inches
Estimated Horsepower:
Approximately 60-70 HP (at crankshaft, may vary)
Estimated Torque Lb Ft:
Approximately 75-85 lb-ft (at crankshaft, may vary)
Carburetor Type:
Typically a single Keihin butterfly or Linkert carburetor (depending on specific model sub-designation and factory fitment)
Fuel Type:
Unleaded gasoline, 87 octane minimum recommended
Safety Ratings:
Not applicable to motorcycles in the same way as automobiles; focus is on rider control and mechanical integrity.
Braking System:
Front disc brake, rear drum brake (common for 1979 models, some may have dual discs or other configurations).
Lighting System:
Headlight, taillight, brake light, turn signals
Frame Construction:
Steel tube frame
Oil Change Interval Km:
Every 3,000 - 5,000 km (1,800 - 3,000 miles) or annually, depending on usage
Primary Chain Tension Check:
Every 3,000 - 5,000 km (1,800 - 3,000 miles)
Spark Plug Replacement:
Every 8,000 - 10,000 km (5,000 - 6,000 miles)
Engine Oil Type:
Harley-Davidson Genuine V-Twin 20W-50 or equivalent motorcycle-specific oil
Engine Oil Capacity Liters:
Approximately 3.0 - 3.4 liters (3.2 - 3.6 US quarts)
Primary Chain Case Oil Type:
Harley-Davidson Primary Chain Case Oil or equivalent (e.g., SAE 50W)
Primary Chain Case Oil Capacity Liters:
Approximately 0.95 liters (1 US quart)
Brake Fluid Type:
DOT 3 or DOT 4 brake fluid (confirm specific recommendation in manual)
Shovelhead Engine Quirks:
Oil leaks (common with age and design), tappet noise, potential for valve seat wear, and vibration-related issues are typical points of attention.
Electrical System Reliability:
Older wiring harnesses can become brittle, and charging systems (especially older regulators) may require attention.
Transmission Engagement:
False neutrals can occur, and clutch adjustment is crucial for smooth operation.
Brand History:
Harley-Davidson, founded in 1903, is an iconic American motorcycle manufacturer with a rich legacy of V-twin engine dominance and cultural impact.
Fx Series Origin:
The FX (often referred to as 'Factory Experimental') line was introduced to offer a blend of traditional Harley-Davidson power with more modern styling and handling, often using larger engines than the Sportster line.
Shovelhead Engine:
The 1979 FX models are powered by the Shovelhead engine, which succeeded the Panhead and was produced from 1966 to 1984. It's characterized by its distinctive rocker boxes resembling shovels.
Production Period:
The FX series has had numerous iterations, with the 1340cc Shovelhead engine being a common powerplant for FX models in the late 1970s and early 1980s.
