Riding with a slightly oversized chain

[confusedcyclist]

I'm just wondering what negative effects would you expect if your bike has 2-4 too many links in a chain? When I bought a new cassette I stupidly assumed I had the smaller of the two sizes, turns out I bought the smaller cassette by mistake. I didn't cut down the chain before going out riding in case I decided to buy the larger ranged cassette later on, but the gearing on the smaller cassette turned out OK for my usual riding. I haven't noticed any problems with shifting since. The rear derailleur has a clutch which I assume is preventing chain slapping etc. What else might I expect. The shifting certainly seems OK!

 

[fossyant]

So long as it's not 'sagging' in 'small small' then you'll be OK. It's like making sure your chain still shifts into 'big big', you shouldn't use it, but you make sure it still works.

 

[I like Skol]

Presumably the smallest sprocket is still the same size? Have you just reduced the size of the biggest sprocket?

If this is correct then there is no problem as the drivetrain i still working within the parameters it was before.

i.e you have replaced an 11-36 with an 11-32. That is no problem as there would likely have been a 32 or close in the original cassette and it was happy to run in that configuration before. You could maybe shorten the chain to its optimal length but in this case it isn't critical and not detrimental to retain the full length of chain.

 

[Ajax Bay]

Shift the chain to small/small. Does the return section of the chain interfere with the lowest part of the cage/guide jockey wheel? Don't quite see the downside of cutting the chain so it's long enough (large/large plus one (inch) link) aka 'the right length'. Just do it.
The negative effect will mainly be heard when you're in small/close to smallest sprocket: the chain will make an unattractive noise as it rubs (see first sentence above).

 

[confusedcyclist]

I have a 1 x 12 XT/SLX setup, so there is no small small combination to worry about. I went from 10-51 to 10-45, so the job is a good-un! So... I'm just carrying a few surplus links.

Now that I think about it, could come in handy in case of a broken link on the road, and the extra weight (...) is no problem, as it is an e-bike!

 

[Ajax Bay]

Your 36t/10t combo is a normal person's small/small. and going from 51t to 45t requires 3t less chain (rear half of sprocket) so 37mm shorter. The test I offered you earlier applies. Running a chain longer than required has zero merit, imo.

 

[T4tomo]

are you using an old chain on a new cassette or is the chain new too? It should be new - otherwise you will accelerate the wearing of the cassette and on a 1X12 set up that isn't cheap.

per Ajax It can lead to suboptimal shifting running too long a chain, but you have quite a high capacity RD on a 1x set up so a chain that works on say 36 x10-52, will equally work on 36 x10-45, as it wasn't too long for the 36-10 combo. but jus beceause its works doesnt mean its the best thing to do.

Personally I would be removing a couple of links so the chain is just long enough to manage the 36x45 if that is your lowest gear, particularly as 1x12 are so damn sensitive to set up anyway, having a longer chain can exacerbate any shifting issues.

 

[GuyBoden]

I use a longer chain on a triple, but using small/small is avoided. The small granny ring is used only with the bigger sprockets on my rear cassette.

 

[Ajax Bay]

That's the theory, @GuyBoden - do you ride much in the dark? Longer chain than what?
Anyway (and doesn't apply to the OP's (too) long chain), I thought I'd share this link to a post from the past: Why-a-worn-cassette-cannot-damage-a-new-chain

 

[GuyBoden]

That's the theory, @GuyBoden - do you ride much in the dark? Longer chain than what?

I don't ride in the dark, but "Longer chain than what?" is a good question when sizing for a triple.

 

[confusedcyclist]

@Ajax Bay I didn't notice any unusual rubbing sounds, but will have a closer look when it's back in the work stand at home.

 

[Ajax Bay]

Chain must be long enough to go large/large plus a (one inch) link.
"On smallest/small there should be no slack in the lower run of chain. The chain should not be contacting itself at the front guide pulley. In the Campagnolo® sizing system, this gap should be [in the range 8-15mm]. However, if the gap is less than 8mm and the chain is not slack and there is no contact at the pulleys [ie gap > 0], it is considered a usable length." Park Tools

If you can't achieve both these two min/max parameters then very likely you are using a chainset/cassette range combo out of spec for your rear mech.
Personally, if I fit a small inner chainring for a hilly ride (eg Mille Pennines or an SR600), I accept that in small/small there'll be a bit of noise if I inadvertently (@in the dark) shift small/small. That noise is a distinct and immediately actionable indicator that I should be in the middle ring.

 

[MontyVeda]

the negative effect of those extra links would be the extra weight you're carrying. Unnecessary weight leads to rider fatigue and faster wearing of bearings, tyres and other components. Remove those extra links ASAP or suffer the consequences

 

[Ming the Merciless]

the negative effect of those extra links would be the extra weight you're carrying. Unnecessary weight leads to rider fatigue and faster wearing of bearings, tyres and other components. Remove those extra links ASAP or suffer the consequences

 

[confusedcyclist]

My bike spontaneously combusted on the way home from work, if only I had acted sooner! 🤯


Just kidding! I removed the links last night whilst I was giving the chain an ultrasonic bath, but noticed no perceptible difference in performance. Except now my derailleur needs adjustment. Does changing chain length change require gear cable tension refinement? I never thought it would.