Noise from eccentric bottom bracket at every pedal

[crazytraveler]

UPDATE.

I am still not sure where the problem is coming from, but defenetely from the "pedal area".

I have tighten harder the chainring bolt (that's the base of the pedal right?) And the pedals as hard as possible; I have move around the eccentric bottom bracket with no change either...

Chain doesn't look too tight.

Maybe something is worn out? But what? And how to check what? I have only riden 4500Km.

[JimK]

I solved my last similar puzzle by putting on new pedals. I got some VP-191 pedals, that I learned about from Andre, off ebay for $15. Swapped them in and my annoying noise disappeared! If you have a spare pair of pedals, it's an easy thing to try. And if you don't, you can just get some inexpensive pedals as a diagnostic test. And you might find you like the new pedals!

[sg37409]

Did you take the chain off the sprockets at all ?
If your chainring and sprocket are even number of teeth each (e.g., 40*16) it will wear so that if you unship the chain and it goes back on to a tooth on an inner chain plate where previously it was an outer (e.g., out by 1 tooth)  it can be very noisy.

I know this from experience. Its been discussed here before and some folks mark the rear sprocket so as 1 tooth is always noticeable, and they mount the chain on an outer plate on that tooth.

Odd number of teeth, then it won't matter.
Bad luck man.

[crazytraveler]

Did you take the chain off the sprockets at all ?
If your chainring and sprocket are even number of teeth each (e.g., 40*16) it will wear so that if you unship the chain and it goes back on to a tooth on an inner chain plate where previously it was an outer (e.g., out by 1 tooth)  it can be very noisy.

I know this from experience. Its been discussed here before and some folks mark the rear sprocket so as 1 tooth is always noticeable, and they mount the chain on an outer plate on that tooth.

Odd number of teeth, then it won't matter.
Bad luck man.

42*17.

Anyways I moved the chain one up and it still make the same noise. I replaced the link for a new one as well and that didn't help.

[crazytraveler]

I solved my last similar puzzle by putting on new pedals. I got some VP-191 pedals, that I learned about from Andre, off ebay for $15. Swapped them in and my annoying noise disappeared! If you have a spare pair of pedals, it's an easy thing to try. And if you don't, you can just get some inexpensive pedals as a diagnostic test. And you might find you like the new pedals!

I will try that, but I got new pedals 1 month ago and the sound didnt start at the same time.

[geocycle]

I agree with Jim about trying a pedal swap.  You've got to try these noises systematically.  Start with removing the pedals, try and get some grease into them if they are the serviceable type, regrease the threads and reattach.  If problem persists, take the cranks off one at a time, regrease taper and reattach. If still a problem check the EBB for nice discrete dimples and tightly secure the bolts.  Next you need to check the chain for a damaged link, the chainring and the sprocket for any burring.  Also check for loose chainring bolts.  After that I would check the saddle rails.  Then is probably the time to think about the BB.

[JimK]

Yeah if the pedals are new... that is a classic sort of failure situation, where a new thing develops a problem right away. It's easy to swap different pedals in. Just go out for a mile spin and you'll know if the pedals were are problem. Just borrow pedals off a different bike if you don't have an extra pair lying about. If it turns out to be the pedals, then you can decide if you want to fix them or get some new fancy ones or just live with the sound or whatever. The initial swap is just for diagnostic purposes.

[crazytraveler]

UPDATE. All checked, problem seem to be the BB.

It is or loose ot worn out.

[Danneaux]

Hi CT!

Thanks so much for the followup; this thread will help others in similar straits in future.

Glad to hear all is sorted for you.

Best,

Dan.

[Matt2matt2002]

I had this noise as well.
It turned out to be one of the points Dan had flagged.
Loose chain ring bolts.

I had removed it to do a proper clean.
When the noise appeared I was stumped.
But Fans suggestion helped me track it down.
I had not tightened all of the bolts up completely.

Once done, problem solved.
They were only slightly loose.
Not even really loose. But enought to creak.
Matt

[Slammin Sammy]

I know crazytraveller's issue has been resolved, which is great news, but just to add another possible factor from my own recent experience, you can get a crunchy sound when the chain is too loose, as well. My relatively new Nomad that has been getting noisier, especially in high gear and standing situations. When I put it up on the stand, I found that as I rode, each link was momentarily slightly holding up on the bottom of the chain ring, then falling away. The chain was loose, but not enough to fall off. The chain line appears spot on as well.

I measured T1-T2, which was 76mm (difference of distances between inside of chain when spread out vs when squeezed together at the midpoint - see the manual). Thorn recommends about 40mm, and no more than 60mm. I tightened the chain ( first time time since building the bike), and the "problem" was solved.

YMMV, but it's worth mentioning. BTW, now that I have made this first adjustment, I don't expect to have to touch it for several thousand km. Time will tell, but it feels like it will be a long time (and a new chain) before I am running over the same dimples on the BB.

PS - I am running 38x16, so I will watch the link alignment, as was mentioned earlier...

[rafiki]

Joining an old thread because I now suffer similar symptoms and I can't track down the cause.

Chain is well adjusted and sparkling clean and teflon dry lubed.
The chainwheel bolts needed tightening but no improvement thereafter.
Eccentric BB bolts tight.
Chainwheel and rear sprocket clean.
The rear sprocket is showing some wear with a bit of sharks fin showing but nowhere near pointy yet.
Pedals removed, checked, regreased and refitted tight.
Each chain link checked for stiffness.
 
Still I have the noise and slight vibration.
BB? It has only done about 13,000 km so I would doubt it?

I'm a bit stumped and rather disheartened.

[geocycle]

Hi rafiki, you don't say whether it is a tick or a gravelly sound, if the former try removing the cranks, greasing and refitting. If gravelly then it is likely to be transmission or bb. If it appears to be coming from the hub when under load tr backing off the skewer tension slightly.

[jags]

there u go so much for changing things that dont need changing BB, next problem the rohloff will probably explode leaving you stranded.

if you went for a shimano  bb you would never have this problem.and if you did a tenner would have you back cycling in silence.and thats a fact..

just saying  now don't go shooting me.

[JimK]

Did the noise start suddenly one day, or has it been building up slowly over time?

Is it a creak or rumble that comes and goes once per crank revolution or is it more steady than that?

The way sound runs around a metal bike frame, these things are notoriously difficult to track! Don't be too discouraged!

You can always just pull the chain off the chainring and spin the cranks just to check if the BB itself is too messed up. Of course a BB problem might manifest only under load. But it seems very unlikely and is surely the last sort of fix you want to try! Be patient, try little tests, you'll figure it out!