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By Erik Hope

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GearInch is a bicycle gear inch calculator for your phone. Use it to find the cog and chainwheel sizes of your desired gear-inch ratio, or to figure out the gear-inch ratio of components you already have.


*Input exactly your wheel size! Support for 650c/700c/20", 24", 26" and 29"(same as 700c) wheel sizes.

*Precise calculations! Calculations include tire width.

*Mountain and road bike tires supported! Tire width input in both inches and mm for mountain and road bike tires.

*Convert in both directions! Input cog and chainwheel sizes to determine their ratio, or see equivalent combinations for an input ratio.

What's New in Version 1.5

* Updated for iOS 7!
* Higher gear ranges for chainwheel and cog!

iPhone Screenshots

iPhone Screenshot 1
iPhone Screenshot 2
iPhone Screenshot 3
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  • Free
  • Category: Sports
  • Updated:
  • Version: 1.5
  • Size: 0.8 MB
  • Language: English
  • Developer:

Compatibility: Requires iOS 7.0 or later. Compatible with iPhone, iPad, and iPod touch.

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