Got a brand new chain. Now major chain slippage.

jojoma

I just got a new chain with my bike tune up, and for the first time I am experiencing significant chain slippage. I believe it's slippage, as I have never experienced something like this before.

When I was going through all my gears, I was in my middle ring (yes, I have a triple) and once I applied some torque, it felt like something shattered in my drivetrain. And it happens every time I apply force while in the middle ring, so that ring is not usable, unless going downhill.

A similar thing also happens in my smallest gear (30x25), but that is because of the 25 and not the 30.

Where should I look first? In two years of riding, I have never had anything like this occur, so it's hard for me to believe that the chainrings and/or sprockets all of the sudden are history. But maybe they are. Thanks

kant314

you need to change the cassette as well as the chain

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PeterF

+1. It was probably worn before, but with the older chain was masking it.

daveornee

+2

http://sheldonbrown.com/chains.html

Scroll down to the section of new chain and worn sprocket.
I suppose it is also possible that your new chain isn't the right on with your drive train and doesn't mate well. Now with so many possible combinations it makes it really easy to not get the right new chain.

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David Ornee, Western Springs, IL USA

Peter@vecchios

New cogset and maybe new middle chainring. Too bad the bike shop that tuned your bike and replaced the chain didn't test ride the thing to find these things before you.

As chain wear they get longer. Cogs ad chainrings wear to the chain. If you wait too long, then put a new and shorter chain on, the chain doesn't engage as many teeth as before, and when you ally torque, like when climbing, the chain actually skips/slips on the cog or chainring. Loud and scary.

dhk2

++, but the LBS shouldn't have sent out the bike this way after you paid for a tune up. Apparently they neglected to ask about total miles on your cassette, or even give your bike a test ride around the parking lot after the "tune up".

Peter, you mentioned the middle chainring. I've never had a problem with chainrings slipping, but when I buy chains, my LBS mechanic always asks about the age of my cassette and chainrings. Last time, at 16K miles, he offered that it might be time to order some replacement FSA rings for my triple. They don't appear noticeably "hooked", or cause any obvious problems, but I can see some "daylight" when I lift links off the chainrings. Perhaps new rings would be quieter and more efficient (ie, less power loss) on a new chain?

tbkahouna

Maybe not the entire cassette, if that is the problem. The smaller cogs on the cassettes on our four bikes all have independant smaller cogs, whereas the remainder are all cast in a single part. The independant cogs are convenient since they are the ones that will wear out first. You may only require to replace one or both of those two smaller cogs. Check with your LBS to see if they stock or can order individual cogs.

Furthermore, I second the motion that you may also have been sold the wrong chain. The last time I bought one at my normally very thrustwothy LBS, the clerk handed me a chain for a ten speed cassette, instead of the usual 7-8-9 cog cassette. The 10-speed chain is narrower and would have a tendancy to slip the cogs.

Cheers,
Ron

jojoma

Thanks for all the insight. I only have about 4000 miles on the group (it's an Ultegra/105 mix that came stock with my Specialized Roubaix). But this gives me a great excuse to upgrade to the full Ultegra SL group.

jojoma

That's some good mileage. Any opinion on these teeth?

Peter@vecchios

Perhaps but the test for chainrings is if they are noisy, skip just like a worn out cog or exhibit chainsuck, not letting go of the chain. All reasons to change a CR. BUT if it 'looks' poor but works over a long ride in many conditions, I would leave it alone. There is no 'powerloss' or gain if the chain stays engaged with the CR or cog.

Peter@vecchios

Sorry, disagree. a 10s chain onto 7/8/9 cogset may not shift well with index shifting but it wouldn't 'skip' like a wornout cog would. I use 10s chains on my shimano DA freewheel(uniglide, twisted tooth, friction shifters) all the time, have one on it now and it works just fine.

tbkahouna

Hello Peter,

I'll have to trust you on that, since your knowledge is based on hard experience. I have not bothered trying the 10s chain on my 8s cassette. I'm going on what our instructor told us at a bike mechanic course. More specifically, he said that the narrower 10s chain may not sit properly on the cogs of a 7s or 8s cassette and, under strain, might skip.

Cheers,
Ron

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dhk2

They look fine from here Before you trust my judgement though, must confess that my DA 9 sp cassette looked fine to me too when I had to toss it out at 10K miles (after it skipped with a new chain). Actually, have never had any trouble from chainrings, even when they started to show some wear. They just don't seem as sensitive to wear as the rear cogs.