
PROX Cast Piston (manufacturer part number: 01.2005.100) — original PROX piston designed for engine refurbishment operations on lightweight cross displacements. Cast aluminum piston, understated finish and domed head, designed for standard compression fitting. Dimensions: Ø 41.00 mm (oversize letter: 100).
This piston is aimed at riders and mechanics looking for a reliable wear part for top-end engine restoration. Its domed head allows for adjustment of the combustion chamber volume according to the cylinder and ring assembly requirements. It is particularly suitable for off-road (cross) practices and fits the models listed below.
Main compatibilities: YAMAHA PW 50 (2024, 2025, 2026) — 50 cc.
Associated spare parts: replacement rings 260213, piston clips CP1010, needle cage 400407. When replacing, check the condition of the cylinder, rings, and lateral play for a fitting that complies with manufacturer recommendations.