Noisy chain, what have I done wrong?

Niffleman

Dear all, I am sure this is a pretty stupid question, and I guess the answer is really easy, but I cannot see the problem.

I have a Bianchi with a Shimano Sora drivetrain, eight at the back and a triple up front. I have been accumulating tools and knowledge to do a bit of my own servicing and I have done a number of things successfully. I have had the bike about a year and over the week end decided to fit a new chain. I was very careful to buy an eight speed compatible chain and removed some links to make sure it was exactly the same length as the old one, although it is not a Shimano chain. I fitted it fine but there is a noise from the chain now. I don't get the sound when I am pedalling, but whenever I freewheel or pedal back there is a slightly mechanical clanking, which doesn't sound good..

What have I done wrong? Is the chain faulty? It seems to run smoothly, with no stiff links. I was quite pleased with myself but I have messed things up somehow. Can anyone with a bit more knowledge and experience help?

dennisn

I doubt it's a faulty chain. Is it well lubed?? Can you put it on a stand and backpedal
it to listen for that noise??? Things like this are hard for someone who can't see or
listen to the bike to really be very helpful. On the sarcastic side, I would say, don't
pedal backwards, it doesn't work, only forward.

Dennis Noward

nodman7

Hi, sounds like it could be the freehub
i had a grinding clicking noise from the back wheel only when freewheeling on my commuter bike, just cheap bog standard wheels so i decided to strip it down, i soon found the problem, hardly any grease and what there was left was rusty, a quick degrease and clean of all parts and inside the freewheel itself, re-greased and put back together and its been perfect ever since
i followed the park tools guide on http://www.parktool.com/repair/readhowto.asp?id=45 for what i wasn't sure about and it went ok, theres also a section on stripping the wheel down and putting back together if you're struggling
i needed a 11mm allen key to get the freehub off the wheel, i think that was my biggest problem, finding one

anyway i hope that helps

XTCRider

Check to see if you have fed the chain through the rear derailleur properly and that its not rubbing across the cage between the 2 jockey wheels. Done this twice myself

nodman7

forgot to say at the start, take the wheel out and spin it while holding the cassette or freehub if you take the cassette off, if the noise is still there then its the freehub etc

well in my opinion anyway

Garry H

XTCRider wrote:

Check to see if you have fed the chain through the rear derailleur properly and that its not rubbing across the cage between the 2 jockey wheels. Done this twice myself

I had this problem as well, when I changed a sora rear meck for a 105. How did you fix the problem? I ended up twisting the cage a wee bit.

craigenty

Garry H wrote:

XTCRider wrote:

Check to see if you have fed the chain through the rear derailleur properly and that its not rubbing across the cage between the 2 jockey wheels. Done this twice myself

I had this problem as well, when I changed a sora rear meck for a 105. How did you fix the problem? I ended up twisting the cage a wee bit.

I think XTrider means that the chain isn't threaded through the mech correctly. Between the two jockey wheels it's easy to get the chain over the top of the little bit of metal which is bent over from one side of the cage. Still works but it's noisy. (I did this once too :roll: )
You need to split the chain and re-thread the mech.



Craig

XTCRider

craigenty is correct that was what I meant , done it twice now , schoolboy error

robrauy

XTCRider wrote:

craigenty is correct that was what I meant , done it twice now , schoolboy error

Just the once for me (so far) :oops:

nodman7

XTCRider wrote:

I think XTrider means that the chain isn't threaded through the mech correctly. Between the two jockey wheels it's easy to get the chain over the top of the little bit of metal which is bent over from one side of the cage. Still works but it's noisy. (I did this once too :roll: )
You need to split the chain and re-thread the mech.



Craig

if this was the problem there would still be the noise when pedalling and

NIFFLEMAN wrote:

I don't get the sound when I am pedalling, but whenever I freewheel or pedal back there is a slightly mechanical clanking

so it can't be the chain fed through the mech wrongly, but then again its only the chain thats changed so i might be barking up the wrong tree altogether

i made the same mistake first time i changed a chain

Gussio

craigenty wrote:

Garry H wrote:

XTCRider wrote:

Check to see if you have fed the chain through the rear derailleur properly and that its not rubbing across the cage between the 2 jockey wheels. Done this twice myself

I had this problem as well, when I changed a sora rear meck for a 105. How did you fix the problem? I ended up twisting the cage a wee bit.

I think XTrider means that the chain isn't threaded through the mech correctly. Between the two jockey wheels it's easy to get the chain over the top of the little bit of metal which is bent over from one side of the cage. Still works but it's noisy. (I did this once too :roll: )
You need to split the chain and re-thread the mech.



Craig

If you don't want to split the chain, it is possible to just unbolt the lower jockey wheel.

craigenty

Gussio wrote:

craigenty wrote:

Garry H wrote:

XTCRider wrote:

Check to see if you have fed the chain through the rear derailleur properly and that its not rubbing across the cage between the 2 jockey wheels. Done this twice myself

I had this problem as well, when I changed a sora rear meck for a 105. How did you fix the problem? I ended up twisting the cage a wee bit.

I think XTrider means that the chain isn't threaded through the mech correctly. Between the two jockey wheels it's easy to get the chain over the top of the little bit of metal which is bent over from one side of the cage. Still works but it's noisy. (I did this once too :roll: )
You need to split the chain and re-thread the mech.



Craig

If you don't want to split the chain, it is possible to just unbolt the lower jockey wheel.

I just tried this in the garage on a 105 rear mech and if you undo the bolt in the lower jockey wheel there is just enough flex in the cage to pull them apart a few mm so the chain drops directly onto the jocky wheel and no longer touches the cage.

Niffleman

Dear all,

Thanks for your kind suggestions. I had a look at the mech and I had threaded the chain through correctly. I then went to youtube and watched a video on setting up the indexing properly. I followed the instructions and this seemed to help. I also noticed the jockey wheels were all filled with gunk and not running smoothly, so I took them out and cleaned them. In addition, I lubricated the chain some more. I am not sure which of these things did the trick, but the sound has gone away now. I was really surprised how gunked up the jockey wheels were, given that it is a road bike, mainly used in fine weather.

Anyway, thanks for all your advice.