Polini

Evolution 3 kit for Vespa 125 Primavera ET3

Italian scooter performance specialist Polini's 58 mm Evolution 3 cylinder track kit for classic 135 cc Vespa models, this kit can be installed on the original Vespa crankcase without boring it - with increased power throughout the rpm band.

The versatile design means it can be installed in either the original or the “turned” position that is often used during the races on track. This position also favours the development and assembly of the muffler. 

The Polini Evolution 3 kit for Vespa with rotary valve induction can be fitted in all the 125 Vespas with crankshaft that have the same measurements as the original. Also available is a Polini balanced crankshaft (# 210.0033) with its connecting rod milled from a solid block that maintains the original 51 mm stroke.

The cylinder is cast in aluminium, with 58 mm bore, to reach a displacement of 135 cc. The liner with nickel-siliceous coating improves the piston sliding due to better wear and abrasion resistance. The transfer ports are designed for racing use, and it has six transfers.

The piston is gravity-cast in light alloy, and it has two S10 chromed cast iron rings. The head is cast in one piece only and some fins have been made under the head plane in order to improve the heat dissipation. The compression ratio has been optimised to achieve the best performance.

POLINI MOTORI SPA

www.polini.com