RST - Plauged with noise

[goosander]

The good news is that the chain has bedded in now and the chain noise is back to normal, but unfortunately the EBB is still creaking like mad despite loads of copper grease and being correctly torqued.

I've emailed Thorn to see if they can help but I think the only thing left to try is to replace the eccentric shell as it is now quite chewed from a combination of repeated adjustment and damage from when it slipped.

[stutho]

Hi goosander,
I know I have asked this before but are you absolutely sure the noise is from the EBB and not form the cranks, pedals or chainring bolts?  (NB Octolink cranks in particular are known to creak when under load – don’t know what cranks you have got.) Is there any chance you could swap the cranks temporarily to check for this?

Its might be worth removing the BB carefully cleaning the threads of the BB and EBB and then remounting the BB.  When remounting don't forget the copper grease both on the threads and on the BB to loose cup interface.  

You mentioned that the EBB was a bit chewed up.  If there are any raised dent / burs it may well be worth carefully sanding them flat - I haven't ever done this myself but my theory is that a raised dent might act like a pivot point.  If you do sand the EBB you will be removing some of the anodising, which may mean you will get corrosion in the future, so make your choice and proceed with care.

That is all I can think of for the time being, good luck and let us know how you get on.


It propable worth removeing the BB carfuly cleaning the threads of the BB and EBB and then remounting the BB.  When remounting don't forget the copper grease both on the threads and on the BB to loose cup interface.  

You mentioned that the EBB was a bit chewed up.  If there are any rased dent / burs it may well be worth carfuly sanding them flat - I haven't ever done this myself but my theory is that a rased dent might act like a pivet point.  If you do sand the EBB you will be removing some of the anodising which may mean you will get corrosion in the future so proceed with care.

That is all I can think of for the time being - let us know how you get on.  

[stutho]

Hi goosander,
I know I have asked this before but are you absolutely sure the noise is from the EBB and not form the cranks, pedals or chainring bolts?  (NB Octolink cranks in particular are known to creak when under load – don’t know what cranks you have got.) Is there any chance you could swap the cranks temporarily to check for this?

Its might be worth removing the BB carefully cleaning the threads of the BB and EBB and then remounting the BB.  When remounting don't forget the copper grease both on the threads and on the BB to loose cup interface.  

You mentioned that the EBB was a bit chewed up.  If there are any raised dent / burs it may well be worth carefully sanding them flat - I haven't ever done this myself but my theory is that a raised dent might act like a pivot point.  If you do sand the EBB you will be removing some of the anodising, which may mean you will get corrosion in the future, so make your choice and proceed with care.

That is all I can think of for the time being, good luck and let us know how you get on.

[goosander]

Hi Stutho,

I got a reply back from Andy Blance, who suggested that it is most likely the BB cartridge at fault and has recommended that I try tightening it using locking compound and if that doesn't work, try a new BB.

I'll probably do as you suggest and try the cranks and BB off my old bike at the weekend as they are both have 73mm BB shells and both cranks are square taper with 42T chainrings, so it should work OK.

[stutho]

quote:Originally posted by stutho

If there are any raised dent / burs it may well be worth carefully sanding them flat

Today I decided to overhaul my drive train including removing the BB (It a very wet Sunday here).  It is the first time the BB has being removed since I fitted it (approx. 7500 miles ago). Anyway I thought I best retract the above comment as on inspection of the EBB I realised that a raised dent couldn't act as a pivot.

As for the BB I found slight corrosion at the cup / cartridge interface which was carefully remove with some 800-grit paper.  (And yes I removed the BB with the EBB sill in place on the bike.)

[goosander]

Good news at last, the bike is currently creak free.  

I swapped cranks with my old bike and had no creaks (and the old bike was fine with the Thorn crank).  After a week running like this I swapped the cranks back and also made sure that the BB was nice & tight, still no noise.

So far its looking promising, but I think I'll give it another couple of weeks before declaring victory.