Historical Context:
The Harley-Davidson Servicar was a utilitarian three-wheeled motorcycle designed for commercial use, popular for delivery services and industrial applications during its production run.
Target Audience:
Restorers, collectors, and mechanics specializing in vintage Harley-Davidson motorcycles and commercial vehicles.
Competitors:
Competitors in the commercial vehicle space at the time included various manufacturers offering light trucks and specialized delivery vehicles, though few offered a motorcycle-based solution like the Servicar.
Uniqueness:
The Servicar's unique design combined the power and simplicity of a Harley-Davidson motorcycle with the cargo capacity of a small vehicle.
Durability:
Built for robust commercial use, the Servicar's construction prioritized reliability and ease of maintenance.
Engine System:
Engine disassembly, assembly, tuning, troubleshooting, and overhaul for the flathead V-twin engine.
Transmission System:
Covered, including clutch, gearbox internal components, lubrication, and adjustment.
Drivetrain System:
Rear drive assembly, including final drive chain, sprockets, and wheel hub.
Suspension System:
Front fork (leading link type), rear suspension for the motorcycle and the integrated motorcycle chassis.
Braking System:
Drum brake system inspection, adjustment, and repair for both motorcycle and sidecar.
Electrical System:
Ignition system, lighting, charging system (generator/alternator), battery maintenance, and wiring diagrams.
Fuel System:
Carburetor service (e.g., Linkert), fuel tank, fuel lines, and fuel pump (if applicable).
Cooling System:
Air-cooled engine thermal management and inspection.
Chassis And Bodywork:
Frame inspection, sidecar attachment, fenders, fuel tank mounting, and general bodywork repair.
Wheel And Tire System:
Wheel bearing service, tire replacement, and spoke adjustment.
General Maintenance:
Oil changes, lubrication points, spark plug replacement, air filter cleaning/replacement.
Engine Overhaul:
Complete engine rebuild, including piston ring replacement, valve guide service, and bearing replacement.
Troubleshooting Guides:
Diagnostic procedures for common performance issues, starting problems, and electrical faults.
Carburetor Adjustment:
Step-by-step guide for tuning the Linkert carburetor for optimal performance and idle.
Ignition Timing:
Procedures for setting ignition timing using timing marks and test equipment.
Brake Adjustment:
Service for front and rear drum brakes, including cable adjustment and shoe replacement.
Wheel Bearing Service:
Inspection, cleaning, greasing, and replacement of wheel bearings.
Electrical Component Testing:
Testing of generator, regulator, ignition coil, and lighting circuits.
Front Fork Service:
Maintenance and repair of the leading link front suspension, including damper service.
Depth Level:
In-depth technical detail suitable for professional mechanics and experienced enthusiasts.
Rebuild Procedures:
Detailed instructions for complete engine and gearbox rebuilds.
Diagnostic Capabilities:
Covers troubleshooting for a wide range of mechanical and electrical issues.
Specifications Data:
Includes torque values, clearances, and other critical specifications.
Engine Type:
Air-cooled, 45 cubic inch (740cc) V-twin flathead
Bore X Stroke:
Approximately 2.75 inches x 3.00 inches (70mm x 76mm)
Compression Ratio:
Varies by year, typically around 5.0:1 to 6.0:1
Valve Train:
Overhead valve (OHV), though commonly referred to as 'flathead' due to the design of the combustion chamber and pushrod layout.
Horsepower:
Approximately 20-25 hp at advertised RPM
Torque:
Approximately 35-40 lb-ft at advertised RPM
Carburetor Model:
Typically Linkert carburetors (e.g., M, ML series variants)
Fuel Delivery:
Gravity feed from tank to carburetor (no fuel pump on most models)
Wheelbase:
Varies, but generally longer than standard motorcycles to accommodate the sidecar and frame.
Length:
Significant variation depending on sidecar configuration.
Width:
Varies, typically dictated by the widest point of the sidecar.
Dry Weight:
Approximately 600-700 lbs, depending on configuration and model year.
Payload Capacity:
Designed for substantial cargo, typically several hundred pounds.
Infotainment System:
Not applicable. This era focused on core mechanical functionality.
Driver Assistance Features:
None. Focus is on mechanical control and rider input.
Connectivity Features:
None. Vehicles of this period predate modern connectivity.
Headlight:
Mechanical headlamp with bulb, often powered by the generator.
Ignition System Type:
Battery and coil ignition with mechanical points and condenser.
Oil Change Interval:
Typically every 1,000 to 2,000 miles, or as specified in the manual.
Lubrication Points:
Regular lubrication of all pivot points, control cables, and wheel bearings is critical.
Tune Up Frequency:
Recommended annually or every 5,000 miles, including ignition and fuel system checks.
Engine Oil Type:
SAE 50 or SAE 20W-50 motorcycle-specific oil (verify manual for exact weight and API classification).
Transmission Oil Type:
Dedicated gearcase oil (e.g., HD Transmission Lubricant or equivalent).
Brake Fluid:
Not applicable (drum brakes use mechanical actuation, no hydraulic fluid).
Grease Type:
High-temperature chassis grease for wheel bearings, pivot points, and steering head.
Carburetor Wear:
Linkert carburetors can be prone to wear in the throttle shaft and needle seat, leading to rough idling and fuel leaks.
Generator Output:
Generators can degrade over time, leading to insufficient charging voltage for the battery.
Wear And Tear:
As with any vintage vehicle, expect wear on frequently used components like cables, clutch plates, and brake linings.
Frame Alignment:
Proper alignment of the motorcycle and sidecar frame is crucial for handling and tire wear.
Founding:
Harley-Davidson Motor Company founded in 1903.
Specialization:
Renowned for its V-twin engines and durable, reliable motorcycles for both civilian and military use.
Introduction Year:
The Servicar concept dates back to the 1930s, with the SV series solidifying its design from the 1940s.
Key Changes:
Over the years, updates included engine improvements, transmission refinements, and chassis modifications to enhance load capacity and handling.
Production Period:
1930s to 1973 (though this manual focuses on the 1940-1958 SV generation).
Manufacturing Location:
Milwaukee, Wisconsin, USA