New chain problem...

[rafiki]

Help, please. I fitted a new KMC X1 chain to my sterling this afternoon. It all went well. The fit is good, the slack is just as it should be. However, on riding out for a test the chain is very noisy under load. What could be causing this? What can I do to fix it? The chainring is 39T, the rear sprocket 16T. The chain has 96 links including the quicklink which is the same as the previous chain. Any help would be much appreciated.

[geocycle]

It sounds as if the chain isn’t meshing with the sprocket or chainring. This sometimes goes away very quickly once the chain flexes a bit. Were the sprocket and chain rings new? If not you could try reversing one or both of them.

[rafiki]

Thanks. No, neither sprocket is new. I will try reversing the chainring tomorrow. I don't have the tool for removing the rear sprocket.

[Danneaux]

Brian,

Picking up from Geo's suggestion: Do the teeth on the sprocket and chainring look worn or hooked? If they are well worn, their pitch will no longer mesh exactly with the new chain, leading to problems such as noise and roughness. Reversing these as Geo' suggested would put new wear surfaces in contact with the chain rollers (provided it has not been done previously, or course ).

There is one other possibility, however remote: When adjusting the eccentric to set chain tension, it is sometimes possible for it to slide sideways just enough to so the chainline is no longer spot-on. It might be worth checking to make sure the eccentric insert is centered in the frame's bracket hanger.

Best,

Dan.

[rafiki]

Hi Dan. Thanks for the suggestions. The teeth don't look badly worn. I recall my old derailleur chainrings resembling sharks fins at times. Nothing like that. I'll have a look at the EBB alignment. It shouldn't be too difficult to reverse the chainring but do you know of any way to remove the rear sprocket without the special tool?

[Danneaux]

do you know of any way to remove the rear sprocket without the special tool?

Sadly, I don't...you need the remover to engage and steady the slots in the driver while you remove the sprocket by turning a chain whip or cog pliers left (all the while making sure the remover is held tightly in place by the hub's quick release).

This is yet another way the Rohloff differs from a derailleur setup: The remover is used to hold the driver still while a chain whip removes the cog. A freewheel is spun off by the remover. A more recent freehub cassette is held still by a chain whip while the remover spins off the lockring so you can pull the cassette stack off directly.

You can substitute a number of things for a chain whip, but the remover is pretty well required.*

Best,

Dan.

*I once removed a friend's _very_ worn Rohloff sprocket by using a tool I made, necessary 'cos the sprocket teeth were too worn to engage a chan whip very well. I just cut a "wrench" from plate steel and set some cylinder head socket head machine screws in tapped holes placed 'round the arc'd head. The screw heads engaged the holes in the sprocket and the cog came off easily.  I wish I had kept it as it was easily among the most worn I've seen. Brian, if uou do change the sprocket, I would suggest upgrading to the splined sprocket and "slim" carrier ("slim" to preserve your present chain line as much as possible). The splined sprockets can be easily changed simply by using a flat screwdriver to pop off a circlip.

[rafiki]

Thanks Dan. I will get the chainring reversed tomorrow and check the EBB at the same time. Then, as geocycle intimates, give it a good run to see if every thing settles down. If not then a sprocket tool, splined sprocket and carrier on order from SJS.

[jags]

is the new chain well lubed

[rafiki]

The chain came with a waxy lube on it. From reading elsewhere I was under the impression that further lube would not be necessary for a while. Perhaps I should lube it anyway and see if there is any improvement.

[martinf]

Probably the rear sprocket. Reverse it or replace it with a new one, as others say the new type spline sprocket that fits on a threaded carrier is much easier to replace once you have got the old screw-fit sprocket off.

I wouldn't bother relubing the new chain, the waxy lube that comes with it should be good for a long time if you don't ride in wet or mucky conditions.

And in my experience, chainrings last longer than sprockets before causing chain problems, so I would only reverse the chainring if the drive is still rough AFTER replacing the sprocket.

[rafiki]

Thank you Martin. I was up very early this morning so I have already reversed the chainring. Having just returned from a short test ride it does sound like it is the rear sprocket. The overall noise level is a bit less and it is more obviously from the rear now so I guess there was a small contribution at least from the front. I shall now have to wait for the removal tool to arrive. In the meantime I think I'll revert to the old chain.

[geocycle]

I may be too late but if you need to loan the sprocket removal tool please pm me.

[rafiki]

I may be too late but if you need to loan the sprocket removal tool please pm me.

Thank you so much for the offer. That is very generous of you @geocycle. An hour ago I received notification of despatch from SJS of 1 removal tool. But thank you again.

[jul]

Hi,

I've the same noise problem after to have replaced my chain by a new one.

 My chainring is a Surly 36 t (5000 kms), i tried to reverse it but it's still noisy. My sprocket is a 17 t (9000 kms) and already reversed at 5000 kms. Both looks in good condition.

I'm planning to ride like that with the parasitic noise because i'm currently traveling with my bike, however, do you think the noise will dissapear quickly ? or it's a risk for all my transmission to ride like that ?

For information, i replace my chain only, every the 4 to 5000 kms, do you think it is a good idea or useless ?

Thanks

[mickeg]

I did not have internet access for a couple of weeks when this thread started, only saw it now.

In the case of a sprocket with an even number of teeth (original post indicated 16T), I have heard that if you put a lot of wear on a sprocket with an even number of teeth, and then make a change so that the teeth that previously had the chain outer plate links now have the inner plate links, that it can be noisier.  The theory is that every other tooth wears more as every other link elongates more as a chain wears.  I am sure this is quite unclear, but this link might explain it better.
https://www.sheldonbrown.com/chain-life.html

I cut a small notch in one tooth on each of my chainrings and also on one tooth on my 16T sprocket.  I am always careful to put a outer plate link on the teeth with a notch cut in the teeth.

This is unlikely to solve the problem for Julio with a 17T sprocket, but the original post cited a 16T sprocket, it may have been pertinent on that one.