Segment:
Big Twin Cruiser/Custom Motorcycle
Target Audience:
Harley-Davidson owners, mechanics, and enthusiasts seeking to maintain, repair, or restore their 1978 Super Glide FXS.
Competitors Era:
Primarily other American V-twin motorcycles, such as Indian (though market share was minimal by this point) and custom choppers, as well as some European marques.
Manual Value Proposition:
Provides authoritative, factory-backed information for accurate and efficient maintenance and repair, essential for preserving the value and performance of a classic Harley-Davidson.
Vehicle Appeal:
Iconic styling, powerful V-twin engine, and the distinct Harley-Davidson riding experience.
Engine Mechanical:
Complete disassembly, assembly, inspection, and repair of the Shovelhead engine (including cylinders, pistons, crankshaft, connecting rods, camshafts, valves, and timing).
Fuel System:
Carburetor (likely a Keihin Butterfly or similar) disassembly, cleaning, adjustment, and troubleshooting; fuel tanks, lines, and petcocks.
Ignition System:
Points ignition system diagnosis, timing adjustment, coil, spark plug, and condenser testing and replacement.
Transmission:
4-speed gearbox overhaul, clutch operation and adjustment, primary drive maintenance.
Electrical System:
Wiring diagrams, charging system (generator/alternator and regulator), lighting, horn, starter motor, and battery maintenance.
Suspension:
Front fork (likely Showa or similar) disassembly, servicing, and fluid replacement; rear shock absorber inspection and replacement.
Brakes:
Front and rear brake system inspection, fluid replacement, caliper and master cylinder servicing.
Chassis And Frame:
Frame inspection, wheel bearing maintenance, steering head bearing adjustment.
Bodywork And Trim:
Fender, tank, and seat removal/installation procedures.
Maintenance:
Scheduled maintenance checks, lubrication points, oil changes, filter replacements, chain adjustment.
Repair:
Step-by-step instructions for common wear-and-tear repairs and component overhauls.
Disassembly Assembly:
Detailed guidance on removing and reinstalling major and minor components.
Troubleshooting:
Diagnostic procedures for identifying and resolving common mechanical and electrical issues.
Adjustments:
Precise instructions for adjusting clutch, brakes, carburetor, ignition timing, and suspension.
Depth:
Comprehensive, covering everything from basic maintenance to complete engine and transmission rebuilds, including detailed torque specifications and clearances.
Digital Format:
PDF (assumed for modern sales, though original was likely print)
Clarity:
High-resolution scans of original factory documentation, ensuring clarity of text and diagrams.
Binding:
N/A (if digital), Perfect Bound/Spiral Bound (if printed)
Paper Quality:
N/A (if digital), Durable paper stock suitable for workshop use (if printed)
Engine Type:
Air-cooled, 45-degree V-twin
Engine Family:
Shovelhead
Displacement Cc:
1339 (81.9 cubic inches)
Bore X Stroke Mm:
8.19 x 10.30 cm (approx. 3.23 x 4.06 inches)
Compression Ratio:
8.0:1 (typical for this era, may vary)
Valve Configuration:
Overhead Valves (OHV), pushrod actuated
Horsepower Hp:
Approx. 60-65 HP (rated at crankshaft, actual wheel HP lower)
Torque Ft Lbs:
Approx. 70-75 ft-lbs (rated at crankshaft)
Carburetor Type:
Keihin Butterfly (e.g., Keihin CV or equivalent for the era)
Fuel Type:
Unleaded Gasoline (minimum 87 octane recommended, check manual for specifics)
Fuel Capacity Liters:
Approx. 13-16 liters (3.5-4.2 US gallons)
Wheelbase Mm:
Approx. 1510-1530 mm (59.5-60.2 inches)
Length Mm:
Approx. 2270-2300 mm (89.4-90.5 inches)
Dry Weight Kg:
Approx. 250-260 kg (550-575 lbs)
Gross Vehicle Weight Rating Kg:
Approx. 450-470 kg (990-1035 lbs)
Crash Test Ratings:
Not applicable for this era of motorcycle; safety relies on rider skill and design integrity.
Braking System:
Front: Disc brake; Rear: Drum brake (standard configurations for the FXS model)
Lighting:
Headlight, taillight, brake light, turn signals.
Frame Construction:
Steel cradle frame for stability.
Oil Change Interval:
Every 2,000-3,000 miles or 3-6 months (check manual for precise interval and oil type).
Primary Chaincase Service:
Inspect and adjust primary chain tension as needed, typically with oil changes or every 5,000 miles.
Spark Plug Replacement:
Approx. 10,000-15,000 miles, or as wear dictates.
Brake Fluid Flush:
Every 1-2 years, or as specified by the manual, due to hygroscopic nature of brake fluid.
Engine Oil Type:
Viscosity typically SAE 20W-50 or SAE 50 for air-cooled V-twins. Check manual for specific Harley-Davidson or API specifications (e.g., API SF/SG or higher).
Engine Oil Capacity Liters:
Approx. 3.0-3.5 liters (3.2-3.7 US quarts) including filter.
Primary Chaincase Oil Type:
Harley-Davidson Formula+ Transmission & Primary Chaincase Lubricant or equivalent (see Transmission Fluid Type).
Transmission Oil Type:
Harley-Davidson Formula+ Transmission & Primary Chaincase Lubricant or equivalent (see Transmission Fluid Type).
Brake Fluid Type:
DOT 3 or DOT 4 brake fluid (verify with manual, as DOT 5 silicone fluid was introduced later but may not be original spec for 1978).
Shaker Clutch:
Potential for primary chain slop and clutch drag if not properly adjusted or maintained.
Shovlehead Oil Leaks:
Common for Shovelhead engines to exhibit minor oil seepage from various seals and gaskets due to their design and age.
Ignition Timing:
Points ignition can drift out of adjustment, affecting performance and fuel economy.
Carburetor Tuning:
Carburetors of this era require periodic tuning to maintain optimal performance, especially with fuel variations.
Foundation:
Founded in 1903 in Milwaukee, Wisconsin, Harley-Davidson is one of the oldest motorcycle manufacturers globally, synonymous with American V-twin motorcycles.
Super Glide Origin:
The Super Glide (FX) was introduced in 1971, marking Harley-Davidson's first major redesign of its Big Twin platform since the late 1940s, featuring a 45-degree V-twin engine (initially the Shovelhead) and a unified chassis.
Fxd Series:
The FXS designation typically denoted a sportier or custom-oriented variant within the Super Glide line. The FXST (Softail) would later evolve from this lineage.
Production Period:
The FXShovelhead engine was produced from 1966 to 1984, with the Super Glide FXS model being a significant part of its application.
Manufacturing Location:
Milwaukee, Wisconsin, USA
