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GI calculators

Old 04-15-12, 07:09 PM
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bfloyd6969
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GI calculators

Looking at the Sheldon Brown gear calculator and the one found on the Wabi site show two significantly different calculations. i.e., the Wabi calc (for 700c) for a 48/18 reads to be a 69gi, but when using the Sheldon calc, and after selecting the correct tire size and crank length reads to be a 67.4gi. Which is more accurate? Which calculator do you all use? Thanks.
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Old 04-15-12, 07:18 PM
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All City.
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Old 04-15-12, 07:28 PM
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I use www.gear-calculator.com. You can calculate a bunch at once, and it's interactive.
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Old 04-15-12, 07:52 PM
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This one has passed around here a lot
https://software.bareknucklebrigade.com/

It even calculates your sw8 skid patches
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Old 04-15-12, 07:54 PM
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I use an iOS app.
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Old 04-15-12, 08:27 PM
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Haven't actually looked into if it;s accurate or not, but this one's simple and quick to use.
https://deafpigeon.co.uk/gear-calculator.php
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Old 04-15-12, 10:16 PM
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Thanks for all the links, everyone!

Interesting - the All City calc matches that of Sheldon's, and the Deaf Pigeon matches that of Wabi's. The ones that have the tire size selection match up and the ones that don't match up...

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Old 04-16-12, 07:08 AM
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The ones without specific size probably round up to 27 for a 700c(it's more ~26.7),hence the bigger number. I usually just calculate myself,easy enough. Chainring/cog x Tirediameter
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Old 04-16-12, 03:14 PM
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Originally Posted by Build your own View Post
The ones without specific size probably round up to 27 for a 700c(it's more ~26.7),hence the bigger number. I usually just calculate myself,easy enough. Chainring/cog x Tirediameter
Thanks. How does the tire width and crank arm length fit into this - as used on the Sheldon gear calculator?
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Old 04-17-12, 05:37 PM
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Increased width also increases height,increasing overall diameter. The Crankarm length on Sheldons calculator is needed to calculate gain. It doesn't effect GI.
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Old 04-17-12, 07:51 PM
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^^ Thanks.
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