Road Cycling - new chain?

assuming you keep your chain in good shape, about how many miles should you expect before having to replace it?

Could be less than 1000 or more than 5000. There are too many variables to predict. Checking for chain wear should be something you do every 500 miles or so. Just use a ruler, line up the 0 and the 12" marks with pins, and if the chain is approaching 1/16" or more longer that 12" it's time to order a replacement.

RichC

chain has about 1,300 miles on it and I measured as you suggested and got 11 15/16

Any suggestions?

If you go by Rich Clark's equasion, which is 12" + 1/16" = 12 1/16", then it looks like you still have 1/8" of stretch to go.

Remember, when you replace your chain, it's not a bad idea to replace your cassette, too. I've put new chains on bikes with old cassettes and had some really bad shifting. If you replace your chain often enough, though, you won't need a new cassette.

Ah, hell, replace 'em both at the same time. Shimano/Campy loves people like me.

Originally posted by mikemets5
chain has about 1,300 miles on it and I measured as you suggested and got 11 15/16

Any suggestions?

The pin-to-pin measurement can't be less than 12". A new chain's links are precisely 1" per pair. The question on a worn chain is how much more than 12" it is. You may need to hold something flat up against the chain while you measure to keep it straight. Be sure to measure the pins center-to-center.

Chains wear differently depending on all sorts of things; maintenance, riding conditions (dirt/dust), how hard you ride, the gear combos you use (lots of cross-chaining is bad), how much time you spend on big cogs and chainrings, etc. Mostly dirt, though. Still, there are too many variations to be able to predict.

RichC

An easier way to check is to take a new chain and the chain off your bike hold them up and then have someone check the ends (assuming that they have the same number of links). A difference of 1/2 of a link on the length of the chain probably means it needs replacing.

Incidentally, I just replaced my chain after atleast 5000 miles on it(don't know what it was) was below the wear threshold. I was warned of skipping that would happen if I only replaced the chain and havn't seen any of that yet.

A guy told me in a bike store 2 weeks ago that you should replace the chain every 1000miles and then the casette every 3rd chain (so every 3000 miles about) which seems like crap....

I replace the chain and cassette every year, which probably comes out to about 2800 miles worth. I could probably replace a chain every 1000 miles and not replace the cassette as often, but what's the fun in that?