1993-2002 Aprilia RS 125 (ZD4DW) Service & Repair Manual

• Covers the 1993–2002 Aprilia RS 125 (ZD4DW) including multiple global homologation variants
• Official Aprilia publication, originally released in November 2002
• Contains 291 pages packed with technical specifications, torque settings, and system diagrams
• Serves as the primary technical foundation for all ZD4DW-frame production units built between 1993 and 2002

When working on the two-stroke engine or chassis systems of the RS 125, having accurate technical data is essential. This service manual provides the exact maintenance parameters, fluid capacities, and torque specs required to keep the bike running smoothly. It breaks down standard service schedules, break-in recommendations, and inspection intervals for critical components like the fuel system, braking circuits, and electrical architecture.

Manual Contents Overview

This documentation is structured to speed up routine maintenance and system inspections in the bay. Instead of guessing, mechanics get direct access to lubrication charts, tire pressure requirements for varying loads, and detailed procedures for managing the fuel tank and carburetor. It even details the setup for the multifunction computer, noting the coolant temperature thermistor range and diagnostic functions. Before performing service on these systems, always ensure you have the proper training and equipment to handle high-pressure fluids and electrical components safely. You will also find clear diagrams and identification notes for frame and engine serial numbers, which is a huge time-saver when matching parts during a rebuild.

Engine and Chassis Specifications

The technical data sections cut straight to the numbers. You get exact engine-specific values, such as the 124.82 cu. cm displacement and the 12.5 ± 0.5:1 compression ratio. Cylinder head bolt torque values are clearly laid out in the fastening element tables to guarantee correct assembly. Other crucial baseline figures include a 0.8-liter coolant system capacity, an engine idling speed of 1250 ± 100 rpm, and an alternator generator output rated at 12 V - 180 W.