johnnyd

Hi,

I have a 10 yr. old bridgestone mountainbike that I'm upgrading. It has a shimano alivio crankset. There is significant wear on the chainrings and I figure I at least need to change these and the chain. I'm thinking about just replacing the whole crankset. How do I know which crankset to choose. My bike has a 21 speed alivio derailleur system with thumb shifters. Should I stick with an alivio crankset, which I know is pretty low end, or can I go for something better without having to replace the derailleur, which still seems to work fine? Also, are chains all the same size for mountain bikes and if not, which size should I get? Sorry for the elementary questions but you gotta ask 'em somewhere.

alcahueteria

The chain for 7 and 8 speeds are the same, maybe 6 too, but 9 speed chains are thinner. You can go back with alivio if you want it just depends on what type of riding you will be doing and how long you want the stuff to last and how much you want to spend. Any of the shimano stuff should work, chainring to derailler wise, I think the bottom bracket may be more of an issue but if your replacing all that other stuff because it's old and worn you may as well replace the bottom bracket too.

sydney

Use whatever crank and matching BB you want. Ues a sram 8 speed chain.