By drawing on the technology used for Formula 1 engines, Polini Motori has designed a thermal unit that sets the standard in the development of Piaggio 300 engines.

Thanks to the special steel cylinder coated with Nicasil and the "HTR" (High Turbulence Ring), it has been possible to increase the bore to 77mm, raising the original displacement from 278 cm3 to 294 cm3: an explosion of incredible power for your scooter's engine.
The thermal unit can be installed without any modifications to the original crankcase and cylinder heads.
A unique feature in the scooter segment is the "HTR" ring, which not only improves the squish effect but also provides a large contact surface for the cylinder head gasket, thus ensuring great reliability of this component.
The piston features a particularly extended skirt to withstand the lateral forces generated by the connecting rod; the combustion chamber shaped in the piston crown is designed to achieve an optimal compression ratio with large squish bands that couple with the original cylinder head.

The casing has two specific curves for the different stages of development: the first is indicated for installation with the Polini Hi Speed variator, original kit and exhaust; the second for installation with the Polini Hi Speed variator, kit and Polini exhaust.
The performance with the new kit is noticeable even at low revs, and the engine performs well at every rotation speed.
The kit is delivered complete with a Plug & Play casing along with the necessary wiring that needs to be connected to the original system without modifications.