Primary gears -POLINI- Piaggio 50cc (1998-)- 13/40 = 1:3.08

Only suitable for vehicles with 17.7mm shaft and support bearing in variator cover.
In case of doubt, please check before ordering.

To extend the gear ratio is useful if the engine power was increased by successful tuning measures. With the extended gear ratio you can convert your increased power into more speed.
In addition, the cylinders and the rest of the engine are protected, because they no longer have to be turned up so high.

In series engines, a longer gear ratio is usually not useful, because the power in most cases is not enough to convert the ratio plus into top speed._{AI-translation}