1974-1976 Harley-Davidson SS/SX-175/250 Service Manual

1974–1976 Harley-Davidson SS/SX-175/250 Factory Service Manual

Available as an instant download, this original 126-page OEM reference (revised December 1975) bypasses generic advice to give you the exact factory specifications needed for the 175cc and 250cc two-stroke singles. Whether you are doing a ground-up restoration or routine maintenance on these AMF-era dual-purpose and street models, this manual is the definitive baseline for your shop.

• Features 35 exploded-view diagrams that map out the engine internals, clutch, transmission, and front forks.
• Documents factory-specified tightening torque values in both ft-lbs and kgm for over 60 critical engine and chassis fasteners.
• Delivers hard technical clearance data for piston-cylinder fits, transmission end play, and starter mechanism tolerances.
• Provides build-specific tuning parameters for the Dellorto VHB27AD and PHB32AD carburetors.
• Includes specialized charts covering how factory workshop documentation is structured to speed up component identification during complex rebuilds.

Chassis, Engine, and Diagnostic Specifications

Working on vintage two-strokes requires exact tolerances, not guesswork. This documentation breaks down front fork maintenance across the three different OEM setups used during production: Marzocchi, Ceriani, and Betor. You will also find dedicated procedures for steering head alignment, rear suspension tuning, and complete lubrication requirements. The exhaust section covers crucial two-stroke maintenance, including carbon removal techniques and muffler service.

For top-end rebuilds, base bore dimensions are clearly defined at 61 mm (175 models) and 72 mm (250 models). The engine tables specify a connecting rod end play between 0.012 and 0.016 inches (0.30–0.40 mm), while the SX-175 intake port piston clearance requires a strict 0.0006 to 0.0018 inch fit. To cut down diagnostic time, the manual also provides complete wiring schematics and ignition timing data.

Always verify these factory tolerances against current workshop safety standards before turning a wrench, especially when servicing pressurized lower ends or handling volatile fuel delivery components.