Andycapp

I just "upgradded" my chain from a Sram pc850 to a Campagnolo C9 8/9 speed chain. It was slipping on the 19t - 23t cogs, 12-17 seemed fine but could be I never mashed them hard enough to jump teeth. First thought is a worn cassette not playing well with a brand new chain. I have no idea how many miles are on the cassette as it was used when I got it, but it doesn't appear all that bad. The thing is the Sram chain isn't exactly old and doesn't show any stretch. I just wanted a pretty silver one with Cs on it. I put the Sram back on tonight and it works fine. So my question is - Is there anything other than worn cogs that might be causing this? These chains (Campy) aren't "directional" in any way are they?

-Andy

Drillium Dude 

Boy, I hope you get a good answer because I'm still having the same issue on the same upper cogs. Drat!

DD

Andycapp

I thought your problem was "ghost shifting"? Didn't you try different cogs too? I hope not, but maybe the answer is get a cheap sram chain !

busdriver1959

Whenever I have tried replacing a worn chain without replacing the cassette/freewheel, I have had problems with the chain slipping. I've looked at the cogs and decided that there isn't any wear so I'd try it. Same results every time, cured by new cogs. Back in the day, a shop would have a cog board and you could just replace the worn cogs. When cassettes came out, the whole process should have been easier but the component manufacturers never sold individual cassette cogs even when groups of them weren't riveted together. That's the long way of saying, buy a new cassette.

cudak888 

Chain skip. The wear of your more frequently-used cogs aren't matching up to the lack of chain stretch on your new chain.

In the case of an older freewheel (Suntour, in particular), you can swap the bad cogs for NOS or lightly-used replacements with little problem. Modern cassettes usually need to be swapped out in tandem with the chain.

-Kurt

cyclotoine

I changed the chain on a campy cassette (10s) and it couldn't have had more than 2000kms on it and it skipped! I could see little to no indications of wear. I was mystified. With 10 speed shimano I have worked on it so much I can tell by looking almost every time. I was really disappointed and still have the cassette hanging around because it looks perfect. Really annoying for how pricey the stuff is. I replaced it with a veloce cassette and called it a day. I still have some old 10 speed chorus because I won't be able to get anything for it, but I am a sram man now with shimano cassettes and chains.

Andycapp

OK, I guess I can accept that. I'll keep the new Campy chain on the shelf until I get a new cassette. However, I still find it strange that a newish Sram chain works fine where as the Campy doesn't, especially on an all Campagnolo drivetrain. Maybe just looser/more forgiving tolerances in the Sram I guess. On a good note, since the Sram does seem to work fine, it's not an emergency situation and I can take my time getting the new cassette and with any luck still get a lot more miles out of this one. I remember reading a post recently about someone "reshaping" the teeth slightly on a worn freewheel to get it to mesh better with a new chain. I wonder if that same idea can work in this case.

Thanks,
Andy