Market Segment:
Cruiser/Touring Motorcycle
Target Audience:
Harley-Davidson owners, mechanics, restoration specialists
Competitors:
Other large-displacement V-twin motorcycles of the era (e.g., Indian, some European marques)
Design Philosophy:
Classic American V-twin cruiser styling and performance, known for torque and distinctive sound.
Iconic Status:
The Shovelhead engine is a highly sought-after and iconic powerplant in Harley-Davidson history.
Engine Systems:
Engine disassembly, assembly, tuning, lubrication, cooling, intake, exhaust
Transmission Systems:
Transmission disassembly, assembly, maintenance, troubleshooting
Electrical Systems:
Ignition system, lighting, charging system, starting system, wiring diagrams
Chassis Systems:
Frame, suspension (front forks, rear shocks), brakes (hydraulic/mechanical), wheels, steering
Fuel System:
Carburetor overhaul (e.g., Keihin, Linkert), fuel tank, fuel lines, fuel pump (if applicable)
Bodywork And Trim:
Fairings, fenders, seat, tanks, controls, instrumentation
Maintenance Procedures:
Routine checks, lubrication schedules, filter replacements, fluid changes, spark plug service
Diagnostic Procedures:
Troubleshooting guides for common problems, symptom-based diagnostics, electrical circuit testing
Repair Procedures:
Step-by-step instructions for component removal, repair, and installation
Overhaul Procedures:
Complete engine and transmission rebuild procedures
Diagnostic Depth:
Advanced, including troubleshooting for electrical faults and engine performance issues
Repair Depth:
Comprehensive, covering everything from minor adjustments to complete engine rebuilds
Special Tools:
Identification and usage of specialized tools required for servicing
Engine Displacement:
74 cubic inches (1200cc) or 80 cubic inches (1340cc) - typically 74ci for FLH models of this year.
Engine Configuration:
45-degree air-cooled V-twin, overhead valve (OHV)
Bore X Stroke:
Typically 3.4375 in. x 4.00 in. for 74ci
Compression Ratio:
Approximately 8.0:1 (stock)
Horsepower:
Estimated 50-60 HP (stock, at the crankshaft, varies with tune)
Torque:
Estimated 65-75 ft-lbs (stock, at the crankshaft, varies with tune)
Carburetor:
Typically Keihin butterfly or Linkert (depending on specific sub-model and production changes)
Fuel Type:
Unleaded gasoline (minimum 91 octane recommended for modern fuels)
Ignition Type:
Contact breaker points and coil, or early electronic ignition options
Wheelbase:
Approximately 61.5 inches
Length:
Approximately 90-95 inches
Dry Weight:
Approximately 650-700 lbs
Gross Vehicle Weight Rating:
Not typically specified with a GVWR in the same way as cars, but payload capacity exists.
Safety Ratings:
N/A (Motorcycles are not rated by agencies like NHTSA in the same manner as cars)
Braking System:
Front disc brake, rear drum brake (typical for FLH models)
Lighting:
Headlight, taillight, brake light, turn signals
Oil Change Interval:
Typically every 2,000-3,000 miles or annually, depending on usage. Consult manual for exact intervals.
Spark Plug Replacement:
Every 6,000-10,000 miles (recommend checking manual for specific plug type and gap).
Drive Chain Lubrication:
Every 500 miles or after washing/heavy rain. Check tension regularly.
Engine Oil Type:
Typically SAE 20W-50 motorcycle oil (e.g., Harley-Davidson Genuine V-Twin Oil, or compatible high-quality mineral or synthetic oil). Manual will specify.
Transmission Oil Type:
Typically SAE 90 gear oil or Harley-Davidson Transmission Lubricant. Manual will specify.
Primary Chain Case Oil:
Typically SAE 20W-50 motorcycle oil. Manual will specify.
Brake Fluid Type:
DOT 4 or DOT 5 (Silicone based for some later models, but 1978 likely DOT 4. Check manual).
Oil Leaks:
Common due to age, aging seals, gaskets, and potential crankcase breather issues.
Carburetor Issues:
Vapor lock, vacuum leaks, jetting issues, especially with modern fuel formulations.
Ignition Timing:
Can be sensitive and require precise adjustment for optimal performance.
Pushrod Tube Seals:
Can degrade over time, leading to oil leaks.
Cam Chain Tensioner:
Early Shovelheads used a fixed tensioner which could wear; later models had improvements.
Brand Legacy:
Harley-Davidson has a long-standing history in American motorcycling, founded in 1903.
Shovelhead Era:
The Shovelhead engine was produced from 1966 to 1984, evolving from the Panhead. The FLH designation historically refers to the large frame touring models.
Manufacturing Location:
Milwaukee, Wisconsin, USA
Production Years:
FLH Shovelhead models produced throughout the Shovelhead engine era (1966-1984).
Model Recognition:
The Shovelhead engine and FLH models are considered classics and highly collectible.
Owner Satisfaction:
Generally high among enthusiasts who appreciate the vintage character, though requires dedicated maintenance.
Emissions Standards:
Manufactured prior to stringent emissions regulations, but manual will cover original specifications.
