Its fine in the workstand, but as soon as I put any power through the cranks there a horrible dullish squeak coming from somewhere on the bike. Seems to be directly related to the downstroke on the crank, but the BB appears fine, and it appears to be coming from somewhere in the proximity of the rear triangle.

Could it be the bearings are shot (in either hub or bb), even though both turn freely in the workstand?

Worst case scenario I’m guessing it may be a crack in the carbon, but can’t see anything on inspection

Either way its already ruined my afternoon ride…

tried it sat down and standing up? could be seat/post

Mech hanger? If you put it in the workstand and pull the back brake can you replicate it?

Could be pedals. If you’ve got another set, try swapping them.
Also worth greasing up your skewers.

Squeaks both standing up and sitting down I’m afraid. In fact its not so much a squeak as almost a clicky/creaky type of sound.

Monkey what do you mean by that exactly? I can only hear it when pedaling, do you mean just sqeeze the brake without pedaling and can I hear the noise?

not the skewer or pedals either. Just changed both!

Nah I mean if you stick the bike in the stand and hold the back brake on then lean on the pedals can you get the noise? If so it might help you isolate where it’s coming from. It might not though!

Definitely worth making sure everything is nicely tight and greased – skewers, mech hanger as mentioned, cassette, make sure none of your chainring bolts are loose, make sure the cranks are nipped up correctly… But you’ve probably already checked all that.

I’m currently in the midst of a similar battle of wills with my bike… I was convinced it was the BB so I replaced it. It wasn’t. This afternoon I stripped, regreased and rebuilt everything in the suspension, and a quick ride up the road gives promising results. We’ll see.

Thanks FMC

Will try a new wheel first, if that doesn’t work then a strip down may be in order. I’m still thinking it might be the bb, but it turns as smooth as you like, so reluctant to start throwing cash at random trying to fix it.

Just strip it down, check and put back together.

Won’t do any harm plus only an hour or two ‘wasted’.

You’ll either find a problem or it’ll go away.

Is it a dry squeak? If so a few squirts of WD40 or GT85 down between the gap between the BB faces and the inside of the crank arms should do it. Worked for me.

its more of a creak. Will strip, cleen and rebuild and take it from there.

ta

Is it BB30?

I’ve had a similar sound when my Cannondale was cracked under the headtube-downtube junction. I rode it for 3 weeks or so until I noticed it while washing the bike.

How to find a noise.

Get a mate to sit on the bike and pull the brakes on, apply power until the noise can be repeated.

Get a metal bar – pipe etc and place one end on everything that could possiblily move on the bike whilst holding the other end to your ear…

You will here the amplified noise

I would consider the stem. I had similar on my ti456 and a new stem stopped the problem. Kind of worrysome when your riding carbon bars!

Does it only happen when you’re putting big torque through the cranks, or when you’re twiddling a small gear? If the former, it could point to the rear dropouts area.

As above; take it to pieces, clean it, re-grease it and put it back together again. It’s pretty much guaranteed to stop creaking.

yep just when I put big torque through it…well when I say big I mean more than bimbling pace…

Had something similar. It was the ht2 crank bolts on the nds. Not greased and not done up tight enough.
Cleaned, lubed, gorilla’ed them up and it’s all good and stealthy now.