Bicycle Mechanics - Gears

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Ecavalino
04-06-11, 10:18 PM
Hey guys.... I have a lemond Zurich stock ... How to I find out what gear ratios I have? And as a newbie can someone explain pro/cons of various set ups? Thanks


Jeff Wills
04-06-11, 10:54 PM
There's a wealth of information online. A good place to learn is the late Sheldon Brown's site: http://sheldonbrown.com/gearing/index.html

dstrong
04-06-11, 10:58 PM
First you need to know how many teeth are on the front chainrings and the rear cogset. Typical fronts include 53/39, 50/34 or in a triple, 52/42/30. Yours could be different. The tooth count is usually stamped on the ring but if you can't find it, count 'em.

For the cogset, again, each gof should have a stamp with the tooth count or you can count 'em.

Once you have all that, google "sheldon Brown gears" and you'll find a link to his gear ratio calculator. After putting in the info for your chainring and cogset, it'll calculate ratios, gear inches and MPH given a certain RPM.

Oh yeah...you'll need to know your wheel diameter (likely 700) and your crank arm length.

Have fun!


Ecavalino
04-06-11, 11:04 PM
Jeff... Brilliant thanks .... Great 101 reading

Ecavalino
04-06-11, 11:06 PM
Hey perfect info.... Time to hang the bike and look for the numbers!

FastJake
04-06-11, 11:06 PM
This article may be helpful in understanding gear theory: http://sheldonbrown.com/gear-theory.html

Counting the teeth on your gears and plugging those numbers into an online gear calculator such as this one http://www.gear-calculator.com/# can give you a lot of information about your setup.

Ecavalino
04-06-11, 11:11 PM
Thanks .... Sheldon Brown site seems to be very popular reference ..., thanks