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chris dilallo

cracked carbon seat tube

I must have torqued my seat post clamp to hard and the result was this small crack  ( i don't remember torquing it... it was creaky when i bought the bike 2 and a half years ago.  and i had brought it back to the shop they said it was my seat and they had tigntend it and i had never had a problem with it creaking since.  Now that I have had my bike re-built and the clamp was re-adjusted (with a torque wrench) it creaks a lot.   My friend told me i should not put the clamp on in the same spot (during the rebuild) so instead i clamped it like 30-40 degrees clockwise.  covering the small piece of the front hole opening with tape so no debris can get in.

However now when i ride the bike it makes a lot of creeking sounds if i sit on the seat while riding.  ( i have only sat on it while ridding for a very limited amount of time.     Any advise on what i should do?  I was thinking about putting it back to the way it was and torquing it to spec. However this obviously this wont fix the crack but im hoping it will stop the creeking.

Any advise would be greatly appreciated.

Thank you!


Can I just make sure I am clear: you want to fix the crack or get rid of the creeking?
chris dilallo

Well if i could fix the crack that would be amazing...  if i can stop the crack from propagating.. that would also be amazing.. i don't know much about carbon fiber so I am not sure how seriously i should take this crack and how to deal with it.

Stopping the creeking would give me piece of mind.. and not constantly remind me that my bike has a crack in it.

So to answer your question i would like to stop the creeking... and if possible fix or prevent the crack from hurting the integrity of the bike frame.

So i am looking for all and any input i can get on this... i will be stopping by a high end bike shop latter today to see what they say and I will post there response on here.
Slapshot 3

Hi Chris
nice to have you on board, I'm going to move this into the Garage thread, hopefully you'll get a few more replies in there.

Look forward to reading your contributions to Justcycling

IMO, carbon bikes can't take very much punishment before it cracks... you are the only one that can make the decision on whether your frame is safe to ride. I'm surprised you're still riding it. You can get cracks fixed on a carbon bike, but I'm sure it will cost you. Compare the quote the bike shop gives to fix it with whether it is worth buying a new one... If i had the dosh, I'd buy a new one straight off as just the thought that my bike is cracked would make me feel uneasy in putting force on it. I know that there are DIY kits available - ttp:// - but I wouldn't trust myself to do that sort of DIY project. If the crack is going to get bigger, I read somewhere that they can drill a hole at the beginning and the end of the crack to stop it from continue cracking ... but I think that is nonsense.

I can see you are in the USA, but these guys in the UK may be worth a call unless you have an equivalent at your end?

This is a tough one. f it was rebuilt professionally, can't you take it back to them and have it redone/checked over? I'm not an expert on torque measurements but some of the more experienced guys on this forum might have an idea...

Be interesting to read what the guys at the bike shop say.
chris dilallo

yea the crack could have been there for over two years.... or could have just recently happened.... i have no idea as i only noticed it when i took the seat post out...

Chris, I can't be of too much help as I doubt I will ever have that problem with titanium Wink but I would definitely check the frame guarantee to see if it can be replaced.  I have a friend that rides with the forces of darkness and is forever banging on about the lifetime guarantee on his Trek carbon frame.  I also know a guy that cracked a Specialized frame after two years while racing and Specialized replaced it no problem.  Definitely worth checking out.

With regards to the creak I would suggest plenty of anti-seize compound on the post and in the tube, also the Campagnolo clamp is asymmetric and as it clamps on the full round is a better bet than most others.

Welcome salut

Oh, and grease the clamp bolt as well before torquing up...

What Gerry says re greasing the bolt and anti-sieze.  Also, put the clamp back where it was ... and don't over torque.

The biggest issue here for me is the crack.  This could be very dangerous - even if it has been there for a while.  It is probably fixable and might still be under guarantee, but please please get it checked out professionally as I wouldn't want you to get hurt.
chris dilallo

So I stoped by a high end bike shop.  And the guy looks at it pretty uninterested and told me bring it back to where u bought it and it might be under some warrenty.  The bike shop u bought it at should fix this for u no problem.

If not he said bring it back and it for some fee.  

I guess this is wat I must do.    that bike shop isnt convinient to get to but if they can fix or replace the frame for will be worth it.

I will call them tomorrow.

Thanks for the great insite guys.


If it is a carbon crack, most of the manufacturers use Calfee in the US for repair.
chris dilallo

cool looks like to fix that crack would cost 200 dollars from these guys.   i just emailed my original bike shop about it and waiting to see what they say... there closed Wednesday so..

Good luck.

Good news so far then. 200 dollars doesn't much if they can sort it out.

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