1991 Ducati 750/900 SuperSport Workshop Manual (P/N 914.7.006.1B)

• Original OEM publication, Print No. 914.7.006.1B (April 1991)
• Serves as the definitive factory reference for the initial production run of the 1991 SuperSport 91 series
• Documents air-cooled 90-degree L-twin engine configurations for the 750 S.S. and 900 S.S.
• Features 47 exploded-view assembly diagrams and comprehensive service tables across 348 pages
• Covers vital components including the Desmodromic timing system, Kokusan electronic ignitions, Brembo brake calipers, Showa inverted forks, multiple-disk dry clutches, Chrome-Molybdenum trellis frames, Mikuni BDST carburetors, and Brembo light alloy wheels
• Details specific maintenance procedures for the toothed timing belts, steering head bearings, alternator rotors, starter motors, gearbox transmission shafts, hydraulic clutch cylinders, exhaust system manifolds, and oil cooling radiators

Manual Content and Chapter Structure

This 348-page factory PDF reference delivers a highly structured breakdown of the 1991 SuperSport platform. It moves logically from routine maintenance to full-scale engine overhauls. Dedicated chapters cover every phase of engine disassembly, component inspection, and exact reassembly for the 90-degree L-twin. You will also find exhaustive sections detailing the Showa suspension components, braking systems, and complex electrical circuits.

For independent mechanics and dedicated DIYers, this guide provides the exact step-by-step instructions needed to bypass expensive dealership labor rates. It covers critical, high-cost procedures like adjusting the precise Desmodromic valve clearances, synchronizing the dual carburetors, replacing the timing belts, and completely overhauling the front forks. Having this factory-level workflow ensures every repair aligns strictly with OEM standards, significantly reducing bay time and preventing damage to delicate engine components.

Working on high-performance motorcycles carries inherent risks. Always verify that your lifting equipment is completely secure and that the fuel system is fully depressurized before beginning any diagnostic or tear-down procedure.

The manual rounds out its technical diagnostics with comprehensive torque wrench settings, hydraulic clutch release data, and detailed fuel system schematics. To fully support the mechanical work, the documentation includes essential wiring diagrams, valve opening diagrams, ignition advance curves, electrical circuit schematics, hydraulic damping charts, and carburetor component views. Analytical indexes make finding specific settings fast, allowing technicians to focus strictly on performance tuning rather than searching for data.

Technical Data and Service Reference

Precise numbers matter when working on early 90s Italian sportbikes. This documentation supplies the exact factory specifications required for accurate servicing and any major repair. It covers foundational data like exact oil capacities, spark plug heat ranges, and proper tire pressures for both displacement models.

Digging deeper into the cylinder heads, the engine data tables specify exact tolerances, such as the 0.08–0.10 mm intake valve operating clearance. You also get detailed insights into the cooling system's air-flow dynamics, which is critical for managing heat dissipation on these air-cooled V-twins.

Suspension and fueling receive equal attention. The text details hydraulic damping settings for the front Showa forks, clearly listing baseline parameters for rebound and compression stages. Fuel system charts highlight the Mikuni BDST 38-B70/B67 carburetor configurations needed to dial in peak efficiency. For daily workshop operations, maintenance tables clearly define strict service intervals, fluid change requirements, and comprehensive fastener torque values. Finally, the documentation lists complete drivetrain specs, including final drive ratios, chain dimensions, and the specific internal gear ratios for both the 5-speed and 6-speed transmissions.