Summary: Learn how to choose gears and gearing on a mountain bike in this free online video on cycling maintenance and repair.
Mickey Denoncourt received a degree in applied physiology from Hampshire College in Amherst, Massachusetts. Mickey is a Category 3 road racer, Semi-professional DH mountain bike racer...read more
"So as a consumer you are faced with this really, really wide array of gears both in chain ring size and the number of chain rings that you want to use whether you want to use 1, 2 or 3 chain rings up front. If you want to use a front Derailleur to shift across 2 gears or 3 gears. If you want to use a chain guide setup that sandwiches 1 chain ring very securely. There are a lot of options that can be really confusing especially for a new mountain biker or somebody that is looking to upgrade the parts that were on their bike stocked to something that is going to be better performing or more durable. Generally if you like to go out and ride and have fun on fairly moderate trails, a three ring chain ring set up is great. It gives you a really wide range of gears. The stocked chain rings you see are a small of a 22, middle of a 32 and large of a 42, so you've got a 22 spread of gears that you can work with. So the 42 combined with different gears in the back are plenty to get you down all sorts of hills real, real fast. I mean 4212 spins out something like 38 miles an hour which is pretty quick. A 2232 is the smallest gear with the 22 in the front and the 32 out back is also a really, really small gear. Spinning that of a 100 RPM's is something like 2 miles per hour so that will get you up some really steep hills without much effort. "
eHow Article: Choose Gears for Mountain Bikes