[Closed] Chain Slipping on Smaller Rear Sprockets

first time i would assume LBS is correct

Second time may just be indexing - did you reset the gears with the new cassette ? Usually dont need to but its the most likely cause now.

IME "drifting" under load on a new chain and cassette is just poor indexing

same fella explaining this

I had this recently, the slipping, needed a new cable and a reindex and all is well in the world again.

Light use since 2007 is a lot of miles. I used to wreck a cassette in under 1000 miles when I rode a lot, so that's only 100 miles or so a year on your Spesh. The cassette I've got on my commuter has done over 3000 miles but it's shot to pieces and won't take a new chain now
It's very difficultt to diagnose "slipping chains" at distance as that's an all-encompassing term lots of people use to describe [u]any[/u] drivetrain malfunction IME. (IME = me LBS mechanic) Could be loads of things.
That said (sigh...) the LBS should have sorted it once and for all. If it needed a new cassette, THEY should have told you and done it at the service and sent you out with a correctly functioning bike. They haven't done a thorough job.

EDIT

I had this recently, the slipping, needed a new cable and a reindex and all is well in the world again.

Point proven. 'Slipping' covers more than one actual problem. 🙂

OP - Where do you live?

Most likely actually skipping on worn front chainring.

Most likely actually skipping on worn front chainring.

That's actually quite rare. Chainrings can take a lot more wear than a cassette can and will usually last 2 cassettes if there's 2 or 3 chainrings in use (As in actually being used, not just fitted to the bike!)

Hi thanks for the quick replies,

[b]JunkYard[/b] - No, didn't reset the gears after fitting the new chainring unfortunately. I can try this, but was just worried I'd do more harm than good as I'm not very experienced with bike maintenance. Could give this a try though if you think it would help.

[b]Larry_Lamb[/b] - Could be the cable, this isn't something I have considered.

[b]PeterPoddy[/b] - Appreciate I should have definitely replaced the cassette before now, having the bike since 2007, but when I say light use I mean the bike has spent the majority of those years not being used at all.

Also, agree that the LBS probably could have been a bit more thorough, but to be fair to them they replaced a couple of sprockets that were causing me problems with some used spares free of charge to see if it helped. They said that if it didn't fix the slipping chain issue then I'd need a new cassette. That's when I purchased a new one and fitted it myself following a guide. However, I appreciate that during my DIY endeavours I could have missed some crucial steps like the need to re-index the gears.

Are there some things I could try myself to resolve this, or do you think I'm going to need another trip to my LBS?

For reference, I'm in the North East.

Cheers,

Ross

Think I've figured what's causing this issue; the chain came off today under load from the middle front chainring.

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Next question is, how easy is this to replace and would you recommend installing a complete new crankset given the age of the bike (2007)?

Thanks,

Ross

Check all the links for a stiff one, effect will be more pronounced on the little sprockets

Hi, sorry can you explain what you mean by checking all of the links for a stiff one? I only seem to be experiencing problems on the middle chainring but just wasn't sure whether I should replace just that or the whole crankset.

Ross

Just the middle one. It's the one most people use most.