Gearing on both Vespas and Lambrettas can be adjusted to suit a lower ratio (for off-road) or a higher ratio for a tuned engine creating more power. In both engines there is a primary drive which transfers power from the crank to the gearbox where gears can be selected.

The primary drive can be changed on a Lambretta without dismantling the bottom end which is very handy whereas the Vespa has to have the crankcases split to gain access to the gearbox. This section deals with possible gearing combinations and what results you can expect to obtain.