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Gearing Calculator

This small utility allows you to test different gear ratios for your Piaggio Vespa gearbox.
Very useful if you have a tuned engine working at a higher rpm interval than the original specification.

The original gearing will then propably be too high to work well with your tuned engine.
By combining tyre size, primary gearing, secondary gearing as well as replacing individual gearbox gear cogs, you can
adjust your gearing to suit your engines' state of tune.

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Tyre rolling distance (circumference) in meters

 (Please use '.' as decimal separator!)

Engine RPM

Gearbox final gearing ratio

Gearbox primary gearing (If not entered above)


Gearbox secondary gearing (for instance 21 - 36)

Speed in km/h

Calculated final gearing ratio

Copyright © 2003 Göran Löfström

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