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