1993 Ducati ST2 OEM Service Manual (P/N 88713.0143)

This 247-page Ducati factory workshop publication covers the Ducati ST2 and its 944 cc liquid-cooled 90-degree L-twin, six-speed transmission, chassis, Marelli injection-ignition system, and electrical equipment. The bilingual Italian/English PDF carries Ducati publication 914.7.018.1A, printed 01/1998.

• Engine and desmodromic valvetrain repair: Covers engine removal and installation, full disassembly and reassembly, cylinders and pistons, connecting rods and crankshaft, cylinder heads, valves, guides and seats, opening and closing rocker arms, camshafts, timing belts and pulleys, the lubrication system, water pump, and final assembly checks.
• Clutch and six-speed gearbox work: Includes dry-clutch pack and housing service, primary-drive removal, gear-selector and shift-fork inspection, gearbox-shaft disassembly, gear, dog, and bearing checks, end-float and shimming data, reassembly, and functional verification.
• Marelli I.A.W. 1.6 M fuel injection and ignition: Describes ECU strategy and inputs, sequential injector control, ignition advance, fuel pump, injector, pressure regulator, intake-air circuit, absolute-pressure and temperature sensors, speed/timing pickup, throttle potentiometer, EPROM replacement, throttle-body synchronization, and idle CO adjustment.
• Showa suspension and steering: Details inverted front-fork removal and overhaul, cartridge, bush, seal, and oil service, compression, rebound, and preload adjustment, rear-shock removal and spring replacement, swingarm and linkage work, steering-head bearings, and frame-dimension inspection.
• Brembo brakes, hydraulic clutch, wheels, and final drive: Covers pad and disc inspection, hose routing, fluid replacement and bleeding, wheel bearings and spindle checks, chain and sprocket service, rear cush drive, and wheel-refitting checks. Faulty calipers and master cylinders are treated as replacement items rather than internally rebuilt components.
• Electrical and reference coverage: Provides the vehicle wiring diagram and legend, battery and charging-system service, starter and spark-plug checks, ignition and lighting component tests, harness-routing views, torque tables, fluid-capacity data, wear limits, clearances, pressure-test specifications, and approved-product tables.

Repair Depth and Factory Reference Data

The manual separates routine maintenance from settings, frame work, engine overhaul, injection-ignition, and electrical chapters. It covers oil and filter changes, coolant service, compression testing, hot- and cold-engine oil-pressure checks, valve-clearance inspection and adjustment, timing-belt tension, chain adjustment, brake and clutch fluid work, and suspension setup. For major repair, it supplies motorcycle and engine disassembly-sequence charts, component inspection points, reassembly notes, and assembly-specific torque tables rather than only service intervals.

Particularly useful illustrations include the motorcycle component disassembly sequence, engine disassembly sequence, lubrication-circuit schematic, front-fork exploded view, fuel injection-ignition system diagram, and electrical schematic with system-specific harness-routing views.

Special-tool tables identify the TDC gauge 88765.0968, closing-rocker spring tool 88713.0143, timing-belt tensioner 88713.1215, MATHESIS engine testers 88765.1068-1072, and Showa fork seal and spacer tools 88713.0960 and 88713.0957. These listings let a repair shop confirm which factory fixtures are expected before a teardown begins.

Fuel-Injection and Diagnostic Scope

The EFI chapter explains how the ECU uses absolute pressure, intake-air and coolant temperature, engine speed and TDC position, battery voltage, and throttle position to control injection quantity, end of injection, and ignition advance. It also documents the fuel and air circuits, component locations, EPROM replacement, and throttle-body setup using MATHESIS, a mercury-column vacuometer, and a CO tester.

Detailed injection-ignition component and harness testing is specified for the MATHESIS tester and follows the separate manual supplied with that instrument; this PDF does not reproduce the tester manual. That distinction matters when selecting the publication for electrical fault isolation.

Manual-Specific Cautions

The manual treats the throttle-body assembly as a calibrated system; partial adjustment of individual stop, bypass, or balance points can upset synchronization and idle mixture. During fork repair, reversing the oil seal or pulling it over an unprotected stanchion edge can damage the sealing lip and cause immediate leakage. The EPROM chapter also warns that incorrect notch orientation or insertion without the specified tool can damage the component or control unit.

Engine internals, fuel and cooling systems, brake and clutch hydraulics, and spring-loaded suspension components carry real shop hazards. Use suitable lifting and support equipment, follow the manual's warnings and special-tool requirements, and have critical brake, steering, timing, or fuel-system repair checked by a qualified Ducati technician when the work exceeds your training.