Creaking Noise From Bottom Bracket Area

[Nevica]

Hello,

I have a Boardman Comp Aluminium Frame racing bike:

Truvativ Elita Crank set with Truvativ GXP cups. Ultegra pedals.

I get creaking from the bottom end when under high strain. ie going up hills. (Although it is hard to locate the sound).

I decided to buy brand new GXP cups to try and start eliminating the creaking sound. These I replaced and find that the creaking has not diminished.

Any idea what the creaking sound is. Could it be the frame or the pedal bearings?

Nevica

[nfmisso]

(05-23-2011, 08:44 AM)Nevica Wrote:  .... Could it be the frame or the pedal bearings?
....

Yes. make sure that the BB and pedal bearings are adequately preloaded. Just because you replaced the BB does not mean that the preload is sufficient.

[Nevica]

(05-23-2011, 09:38 AM)nfmisso Wrote:  

(05-23-2011, 08:44 AM)Nevica Wrote:  .... Could it be the frame or the pedal bearings?
....

Yes. make sure that the BB and pedal bearings are adequately preloaded. Just because you replaced the BB does not mean that the preload is sufficient.

Preload? Could you explain please?

Nevica

[nfmisso]

http://www.nmbtc.com/bearings/engineering/preload.html
http://www.promshop.info/cataloguespdf/kbc10.pdf
http://www.brighthub.com/engineering/mechanical/articles/17347.aspx

[CNS]

(05-23-2011, 08:44 AM)Nevica Wrote:  Hello,

I have a Boardman Comp Aluminium Frame racing bike:

Truvativ Elita Crank set with Truvativ GXP cups. Ultegra pedals.

I get creaking from the bottom end when under high strain. ie going up hills. (Although it is hard to locate the sound).

I decided to buy brand new GXP cups to try and start eliminating the creaking sound. These I replaced and find that the creaking has not diminished.

Any idea what the creaking sound is. Could it be the frame or the pedal bearings?

Nevica

I have also experienced the same problem with shimano xt external bb. Remove the the crank and the bottom bracket from the bike. Clean everything for old grease. Reassemble the bottom bracket with lots of new teflon waterproof grease on the threads and the sides of the external BB. Grease all the surfaces of the spaces too. Keep it nice and tight. Wipe away excess grease. Reinstall the crankset. Should do the trick.

[Nevica]

I found the creak after a long search.

I took my pedals of and greased the threads with copper ease. Now, no more creak!!!!

Nevica