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~ Gear Ratio Calculator ~

This calculator will work out the speed give or take a bit for each rev range. Sorry but Bike engines not included yet.
* Drop Down Menu's may not work correctly on this page *

Tyre Size: Width (mm)
Profile (%)
Diam (in)
Diff Ratio
Display in:
Gear Ratios: 1st Gear
2nd Gear
3rd Gear
4th Gear
5th Gear


Gears/RPM 1st 2nd 3rd 4th 5th
1000  Rpm
1500  Rpm
2000  Rpm
2500  Rpm
3000  Rpm
3500  Rpm
4000  Rpm
4500  Rpm
5000  Rpm
5500  Rpm
6000  Rpm
6500  Rpm
7000  Rpm
7500  Rpm
8000  Rpm