Primary gear incl. primary repair kit -POLINI- Vespa PX, T5, Cosa, Rally, Motovespa TX, CL, DN, DS, Iris, LML - 64 teeth (straight toothed)

The so-called primary drive consists of the clutch pinion and the primary wheel. The primary gear is in frictional connection with the primary reduction gearing. Which drives the gear wheels. The ratio of these two toothed pinions results in the primary transmission ratio.
If you have positively influenced the performance of your engine, then a longer transmission ratio makes sense, so that the engine converts the extra power into a higher top speed.
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