I change out the chain on my ride that's powered by a Shimano Nexus 8 every 2000 miles or until it looks like I can't push the hub back any further without losing the wheel on a large bump.

I have to change chains at 1800 miles if I want to keep the drivetrain in shape; I ride over gravel/clay/sand (sticky!) 8 miles a day so if there's any moisture on the ground, my chain is extremely dirty within 1 mile of my house even if it started out new.

I let it go too long about a year ago, and when I put the new chain on, it was skipping. I put the old chain back on again and rode it all summer, which was about 3000 more miles. I finally replaced the freewheel ($12) and chain ($4.50) 2 weeks ago. I'm oiling every 2 days in this weather; the chain was rusty and didn't bend on all the links within 48 hours of putting it on with factory lube; water, sand and road salt is hell.

Does FG really wear less, or does it just not matter if it wears? If I left my derailler bike in the same gear all the time, all the sprockets would wear along with the chain and it would be OK. Plus it's not possible for the chain to skip. Do you just let it wear, then replace all the sprockets at once? (actually, flip the sprockets over, go another X thousand miles, then replace them?)

I was sitting here, reading this thread and thinking "Man, the old 7-speed chains must be lots more durable because I've put about 1000 miles on it this winter with no problem...

*gets up...looks at bike...* "D'oh!!!"

So I'll be getting at least a chain and a freewheel. That's OK, it was getting a bit elderly anyway. If I can get it through the winter I'm planning on replacing a lot of the drivetrain anyway with parts that are low-end for 2008 as opposed to low-end for 1992.

I'm at the point of winter (roadgrit and endless rain) where I should really check my chain. Don't want to see what I might find, although I do actually have a spare cassette right now so I don't have to go get one. Between that and the brakepads (can they make it until I switch back to 'regular' rims from the winter ones...) there's just stuff I don't want to deal with right now.

I switched from 8 to 9spd a year ago and the chains are wearing out MUCH faster, i am dissapointed to report. I check chain wear with the Park tool pretty often and only get around 1000miles out of the 9spd. :(