🏷️ Basic Information

Make:

Harley-Davidson

Model:

Electra Glide / Super Glide

Year:

1978

Engine Family:

Shovelhead

👋 Introduction

Era Context:

The 1978 Electra Glide and Super Glide represent classic American cruiser motorcycles from a period of significant evolution for Harley-Davidson, bridging the gap between older designs and more modernizations.

Historical Competitors:

Competed primarily with other large-displacement American motorcycles and increasing influence from Japanese manufacturers in the touring and cruiser segments.

Model Segment:

Large-displacement touring (Electra Glide) and cruiser (Super Glide) motorcycles.

Engine Type:

Air-cooled V-twin, the iconic 'Shovelhead' engine.

Distinguishing Characteristics:

Robust build, characteristic V-twin sound and feel, designed for long-distance riding (Electra Glide) and stylish cruising (Super Glide).

📋 Manual Details

Primary Coverage:

Comprehensive service and repair for 1978 Harley-Davidson Electra Glide and Super Glide models.

Secondary Coverage:

Includes troubleshooting, routine maintenance, and detailed component overhauls.

Estimated Pages:

Extensive (specific count not provided, typical for full service manuals of this era is 300-500+ pages).

Type:

Full Service Repair Manual

Language:

English

Format:

Likely Print (based on traditional manual sales, digital formats also common).

📖 Manual Coverage

Engine:

Engine disassembly, assembly, tuning, lubrication, cooling system, ignition system (points, coil, condenser), carburetor overhaul and adjustment (e.g., Keihin, Bendix/Zenith).

Transmission:

4-speed gearbox, clutch service, gear shifting mechanisms, primary drive system.

Chassis:

Frame, front fork (leading axle), rear suspension (shocks, swingarm), wheels, bearings, steering head.

Electrical:

Wiring diagrams, lighting system, battery, charging system (generator/alternator), starter motor, ignition switch, accessory circuits.

Brakes:

Front and rear brake systems (likely drum brakes, possibly early disc brake systems depending on specific sub-model/options), hydraulic components, linkage.

Fuel System:

Fuel tank, fuel lines, petcock, fuel filters, carburetor.

Exhaust System:

Exhaust pipes, mufflers, mounting hardware.

Maintenance:

Regular service checks, oil changes, filter replacements, lubrication points, tune-ups, pre-ride inspections.

Repair:

Component disassembly, cleaning, inspection, repair, and reassembly for all major systems.

Troubleshooting:

Systematic diagnostic procedures for common and complex issues, based on symptoms.

Specifications:

Torque values, clearances, timing settings, fluid capacities, and other critical technical data.

Depth:

Comprehensive, covering everything from basic maintenance to complete engine and transmission overhauls, including electrical system diagnostics and component-level repairs.

📊 Manual Specifications

Digital Format Quality:

If digital, expect clear scans of original factory pages. Searchable text functionality depends on OCR quality.

Print Quality:

Original manuals were typically high-quality prints with clear diagrams and text.

Binding Type:

Originals were often stapled or perfect bound; reprinted versions may vary.

Paper Type:

Originals used durable paper suitable for workshop environments.

⚙️ Engine Specifications

Engine Configuration:

Air-cooled, 45-degree V-twin

Engine Displacement:

74 cubic inches (1213cc) - common for the era.

Bore X Stroke:

Approximately 3.4375 in x 4.25 in (87.3 mm x 108 mm) for the 74ci Shovelhead.

Compression Ratio:

Typically around 8.0:1 to 8.5:1 for standard models.

Valve Train:

Overhead valve (OHV), pushrod-actuated

Ignition System:

Battery and coil, points ignition system with mechanical advance.

Horsepower:

Estimated 55-65 HP (net) at the crankshaft, depending on tuning and specific engine build.

Torque:

Estimated 65-75 ft-lbs (approx. 88-102 Nm) at lower RPMs.

Carburetor:

Various options, commonly Keihin Butterfly, Bendix/Zenith-Stromberg, or Linkert (though Linkert less common by '78).

Fuel Type:

Unleaded gasoline, minimum 87 octane (RO)`N

Oil Capacity:

Approximately 3 quarts (2.8 liters) for the engine/transmission dry sump system.

Oil Type:

Harley-Davidson recommends specific V-twin motorcycle oils (e.g., 20W-50, though modern equivalents are often used). Refer to manual for exact specifications.

🔧 Transmission

Type:

4-speed constant mesh, foot-shifted, hand-clutched.

Gearbox Options:

No common optional gearboxes for this year/model.

Primary Drive:

Primary chain drive to transmission.

Final Drive:

Belt drive.

Clutch Type:

Wet multi-plate clutch, cable-actuated.

Transmission Oil:

Refer to manual; typically specialized motorcycle gear oil or Harley-Davidson recommended fluid.

📐 Dimensions

Wheelbase:

Approximately 60.5 inches (1537 mm).

Length:

Approximately 90-95 inches (2286-2413 mm).

Dry Weight:

Around 650-700 lbs (295-318 kg) depending on specific model configuration (Electra Glide typically heavier due to fairings and accessories).

Gross Vehicle Weight Rating:

Typically around 1000-1100 lbs (454-499 kg).

Front Tire Size:

Commonly 3.50-19 or 4.00-19.

Rear Tire Size:

Commonly 4.00-18 or 5.00-16.

Wheel Type:

Spoked wheels, chrome or painted steel.

Wheel Bolt Pattern:

N/A for spoked wheels, axle mounting.

🛡️ Safety Features

Crash Test Information:

Motorcycles of this era were not subject to standardized crash testing as seen in modern vehicles. Safety primarily relied on rider skill and mechanical integrity.

Braking System:

Drum brakes front and rear, with mechanical actuation. Some later 1978 models may have featured early disc brakes on the front.

Suspension:

Telescopic front fork with ~4-5 inches travel, dual rear shock absorbers with adjustable pre-load.

Lighting:

Headlight, tail light, brake light, turn signals (front and rear).

Wind Protection:

Electra Glide models featured a large fairing (e.g., 'Batwing') for rider wind protection and luggage carrying.

💡 Technology Features

Audio System:

Optional (rare for 1978), typically aftermarket radio installations.

Electronic Aids:

None. Technology was basic and mechanical.

Connectivity Features:

None.

🔧 Maintenance

Oil Change Interval:

Typically every 2,000-3,000 miles (3200-4800 km) or annually, whichever comes first. Refer to manual for exact specifications.

Primary Chain Tension:

Periodic checks and adjustment are critical for transmission longevity. Interval varies, check manual.

Ignition Timing Check:

Recommended at major service intervals to ensure optimal performance and engine health.

Engine Oil Viscosity:

20W-50 is common, but consult the specific manual for the recommended viscosity for various temperature ranges. Modern synthetic V-twin specific oils are often preferred.

Transmission Oil Type:

Specific gear oil for the 4-speed transmission. Modern equivalents like Syn3 or dedicated motorcycle gear oils are often used, but must be compatible. Consult manual.

Brake Fluid Type:

If disc brakes are present, typically DOT 4 hydraulic fluid. For drum brakes, lubricant for cables and pivot points.

Primary Drive Chain Wear:

Wear on the primary drive chain and sprockets can lead to noise and shifting issues. Proper tensioning and timely replacement are key.

Points Ignition Maintenance:

Points and condenser require periodic cleaning, gapping, and adjustment for reliable ignition.

Carburetor Tuning:

Carburetors of this era can be sensitive to altitude, fuel quality, and require regular adjustment and cleaning.

Oil Leaks:

Vintage Harleys are known for minor oil seepage. Proper gasket and seal maintenance is important.

Shifter Mechanism Wear:

Wear in the shifter linkage can result in sloppy gear changes.

Electrical Connections:

Corrosion or loose electrical connections can cause intermittent issues with lighting and ignition.

📚 Vehicle History

Founding Year:

1903

Brand Identity:

Iconic American motorcycle manufacturer known for its V-twin engines, touring bikes, and cruiser culture.

Electra Glide Lineage:

The Electra Glide line has been a flagship touring model for Harley-Davidson since the mid-1960s, evolving through various engine platforms (Panhead, Shovelhead, Evolution).

Super Glide Lineage:

The Super Glide, introduced in 1971, was Harley-Davidson's first factory custom and sport-touring motorcycle, featuring a sportier styling than the Electra Glide.

Manufacturing Location:

Milwaukee, Wisconsin, USA.

Key Period Challenges:

The late 1970s were a period of transition and challenges for Harley-Davidson, with increased competition and internal restructuring.

🏆 Awards & Recognition

Historical Significance:

These models are considered icons of American motorcycle manufacturing and are highly sought after by collectors and enthusiasts for their heritage and classic riding experience.