Small primary gear -BGM PRO 2.56->2.46- Vespa V50, PV125, ET3, PK50, PK80, PK125 - 28 tooth 51567

All smallframe motors always have the same gear steps (except for three-speed and automatic). A longer transmission ratio is only achieved ex works by so-called primary transmissions of different lengths. These transmission ratios are available in numerous gear steps. How long this transmission ratio should be depends on the available displacement and the power delivery of the engine. In the large class (the cubic capacities from 125 cc upwards) it is not necessary to extend the primary of the 125`s (2.54) again. Here, the increased speed of the racing cylinders compared to the standard version provides a substantial increase in speed.
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