Polini Big Evolution reeds box Piaggio scooter 50cc

The new reed valve Polini BigBore Evolution immediately stands out for its larger diameter.

It is a modular system based on a CNC-machined aluminium support.

The kit is supplied with 0.30 mm thick carbon reeds.

Due to the larger diameter of the reed valve, the engine block intake must be enlarged to 39.5 mm in width.

The Polini Big Evolution reed valve has been specifically developed for carburettors from 24 to 28 mm.

It improves the gas flow, achieving a better throttle response.

Note: the size of the reed valve housing must be increased as indicated in the instructions (39.5 mm).