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Discussion Starter · #1 ·
Anyone have a problem with Shimano bottom brackets unscrewing from the frame such that the drive side crank arm is pulled out awayed from the frame? The non-drive crank arm is pulled towards the frame. I ride a Colnago CT-1 with Italian threaded BB. The frame is Ti, so luckily the bb was not stripped, according to my LBS (i have not picked up the bike yet).

I orginally had a dura ace bb installed, but replaced it with ultegra for durability reasons. I never experinced this problem when the dura ace was installed. So I'm wondering if it has to do with compatibilty issues with the ultegra product line.

BTW my LBS suggested that I consider replacing the group with Campy as Campy might be more compatable as it is Italian made. I find this hard to believe as many of the pro's ride dura ace on Italian frames including Colnago with no problems.

Any help is greatly appreciated.
 

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Discussion Starter · #5 ·
curlybike said:
This is a common occurance on Italian frames regardless of the name on the parts. Yiur Ultegra bb was not installed to the proper torque spec as listed in the Shimano literature and if the LBS did it, shame on them. With their comment on Shimano vs Campy it is obvious where the problem is.
thanks. My lbs cautiously indicated that the problem was fixed. When I pick up the bike today I will ask him about propoer torque.
 

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Discussion Starter · #6 ·
terry b said:
That's rich - drop Shimano and replace it with Campy because the Italians know how to make Italian-threaded BBs better.

Go back and tell them to set their torque wrench (assuming they have one) to 70Nm or, if they cannot understand Newton-meters, 50 foot-pounds. You might also suggest they read the installation instructions.

(Note, the same thing happened to me back when I thought all you needed to do was give the BB a good hard twist. Live and learn.)
Thanks for the detail information regarding propoper torque. I will be sure to relay this to my lbs.
 

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Discussion Starter · #7 ·
Spunout said:
These guys are on crack. First they can't torque a BB correctly, then they fire the above at you.
I don't have any concerns regarding my lbs' skills (yet). The shop is a pro shop which typically only deals with high-end bikes. The problem may be more a factor of which mechanic corrected the problem last time. I have my doubts about some of the mechanics.
 
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