Slipping Chain

[jgspin]

So I replaced my Shimano chain with a new KMC chain and the chain skips. I actually fell going out of the saddle on a climb when the chain skipped. I don't know if it's skipping on the chain ring but I suspect it is skipping on the Shimano cassette which has about 1500 miles. So I took out the KMC and put it side by side with the older Shimano chain which has about 3500 miles and the KMC is about 3/8th of an inch shorter. They have the same number of links. I put the Shimano chain back and no skipping.

Is the KMC incompatible with Shimano cassettes? If I buy a new cassette, shimano or sram will I still have skipping problems?

[Bob Loblaw]

Most likely it's a worn cassette. KMC chains are fine.

BL

[thwart]

Does it skip on many cogs? Usually it's only one or two. Those are classic symptoms of a worn cassette. As long as you use it with a similarly worn chain, things are OK... well, for a while anyway.

But a new chain doesn't match up with the worn cassette cogs, and you've got trouble.

Solution = new cassette.

[SoCalSteve]

Sounds like a worn cassette to me...

Good luck!

Steve

[oldpotatoe]

So I replaced my Shimano chain with a new KMC chain and the chain skips. I actually fell going out of the saddle on a climb when the chain skipped. I don't know if it's skipping on the chain ring but I suspect it is skipping on the Shimano cassette which has about 1500 miles. So I took out the KMC and put it side by side with the older Shimano chain which has about 3500 miles and the KMC is about 3/8th of an inch shorter. They have the same number of links. I put the Shimano chain back and no skipping.

Is the KMC incompatible with Shimano cassettes? If I buy a new cassette, shimano or sram will I still have skipping problems?


Cogset cogs worn out, which ever ones are skipping. Newer(shorter) chain doesn't engage as many teeth, casung the skip. KMC chain(same 'speed' as cogset, yes? 9s-9s, 10s-10s?).

KMC chains are completely compatible with shimano, sram and Campagnolo. Just make sure the 'speed' of the chain matches the cogset 'speed'

Get a 105 level cogset, great cogsets, less than those above it which just have some extra carriers to weigh less. Better than sram, IMHO, any of them.

[markie]

In addition to the cogset you might well need chainrings, too.

[moose8]

my new shimano 6701 chain was skipping and it turned out to be the plates separating from the pins in a couple of places on multiple links. When I called Shimano they said it's rare, but happens given the sheer number of chains they manufacture. I still need to send it back for the warranty process, but the bike shop that looked at it also said it was a defective chain and nothing I did could have played a role (as I really wanted to learn from it if it was something I did). The results were not pretty (chain snapped and pulled the rear derailleur into the rear wheel) and left me stranded 50 miles from home on a 45 degree day. The chain didn't skip on the stand, but only under load, so I would take a really careful look at the individual links.

[toaster]

Jgspin, go out and replace the cassette with a new one and re-install your new KMC chain and let us know how that worked out.

It's obvious when you state a 3/8" difference in length that the original chain is worn out. The cassette is history, too.

You can search the subject here or elsewhere that a chain that measures 12" pin to pin anywhere along it's length when new should be replaced when that measurement stretches to 12 1/16" to 12 1/8" pin to pin, regardless of mileage.

The trick, of course, is in the way the chain has been kept clean and lubricated during it's service life that determines the mileage. Dirty, greasy chains = less miles, whereas clean, shiny chains = more miles.

[TeamSwami.com]

I had a similar issue with a SRAM Force setup. I was getting chain slippage when on the 36 ring when launching off of a light/stop or heavy climbing tension. None of the components were old and I "chain checked" the chain and I ruled out wear. At one point I thought it was the hub cassette body and torn it apart and rebuilt. I read a few posts here and there about tension and applied more tension than I would normally have to the rear derailleur "b tension" screw. So far it seems to have worked but then again I've been timid to stomp on it off the line.

[Dave]

The B screw only keeps the upper jockey pulley from rubbing on the largest cog. It has no effect on chain skip. Chain skip is a failure of a new chain to engage the worn out cogs under a heavy chain tension. There is more chain tension when using the small chainring.