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Old 08-25-08, 06:24 PM
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Originally Posted by angelaharms
I want to understand gears better. Anybody want to help?

Current bike has 38T crank, and 7 gears in back, ranging from 13-34T. Considering a bike with three gears in front, 28/38/48T, and the back is 8 gears, 11-34T.

I know that the tires and geometry will make a difference, but what I'm after now is to understand the math here. Clearly, I have approximately the same gear range on the old bike as on the new one in second. But I'd like to be able to understand it in more detail.

How can I tell what specific set of gears will match another specific set? Anybody know a formula?

Angela
There are many interpretations of gearing, but I think gear inches is as useful as any. Bill gave you a great 5-minute lesson. In setting up the gearing for a particular bike, the first questions are, how high and how low do I need? Your bike under consideration will go as low as almost any bike and similarly as high, so you shouldn't need any easier or harder gears.

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