Bottom Bracket Retrofit
02-26-21, 08:46 PM
#1
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Bottom Bracket Retrofit
I’ve currently installed a Campy 70mm Italian) BB with a 111mm spindle, coupled w/ a mid-90’s Chorus Crank in the bike. Works & shifts as it should.
I’d like to install an Omas Italian Ti BB (70mm) that has a 114mm spindle. It’s a moveable (sliding) BB w/ 2 adjustable cups.
Will this fit/work w/o issue?
I’d like to install an Omas Italian Ti BB (70mm) that has a 114mm spindle. It’s a moveable (sliding) BB w/ 2 adjustable cups.
Will this fit/work w/o issue?
02-26-21, 09:16 PM
#2
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Apparently Omas uses an ISO taper, but it's going to depend on being able to insert the drive side cup 3 mm deeper into the shell of the frame and still have enough threads showing to put the lock ring on it. Because if you leave the excess spindle on the drive side, you'll just screw up the chain line.
Here's a guy selling one with a 109 mm spindle. https://www.ebay.com/itm/27393195603...f7cbf56bf689d5
But personally, if there's nothing wrong with the Campagnolo unit, I wouldn't change it.
Here's a guy selling one with a 109 mm spindle. https://www.ebay.com/itm/27393195603...f7cbf56bf689d5
But personally, if there's nothing wrong with the Campagnolo unit, I wouldn't change it.
02-26-21, 09:30 PM
#3
Clark W. Griswold
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I personally wouldn't change it. If your Campy unit works stick with it. Changing your spindle length will require other adjusting of the front derailleur to accommodate for the new position of the cranks. Yes you could adjust it out and have your NDS crank be farther out and such but why?
I love Ti but replacing a working unit with something that isn't the same dimension wise just because it is made of a cool material is kind of silly.
I love Ti but replacing a working unit with something that isn't the same dimension wise just because it is made of a cool material is kind of silly.
02-26-21, 09:31 PM
#4
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Thread Starter
Here's a guy selling one with a 109 mm spindle. https://www.ebay.com/itm/27393195603...f7cbf56bf689d5
But personally, if there's nothing wrong with the Campagnolo unit, I wouldn't change it.
But personally, if there's nothing wrong with the Campagnolo unit, I wouldn't change it.
I’m Trying to knock-off some weight on this one.
I’m familiar w/ the seller of that Omas 109 BB.
We don’t exactly meet eye to eye . . . 👀
But, Thx for the suggestion
Last edited by 1 Lugnut; 02-26-21 at 09:38 PM.
02-26-21, 09:42 PM
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Within what each of calls their "reason" BB weight is pretty much a non factor in real life. Besides the small scale reading difference is the stiffness of the spindle factor. For the same OD the Ti will be about 2/3 the stiffness of the steel one. Some riders are smooth enough pedallers so this is no big deal. But if you're a large guy and/or pedal squares perhaps not what with the chain rub increases to be expected. That said I do agree with oldbobcat is regard to the cup/lock ring aspect.
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AndrewRStewart
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02-27-21, 08:14 AM
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Your 111mm Campagnolo bottom bracket is a symmetrical spindle for C-Record and newer cranks. The 114mm OMAS bottom bracket is probably intended for a preC-Record asymmetrical (Record/Super Record or equivalent) road crank. That both sides of the OMAS unit are adjustable means it's possible it could work, but you may find there is no exposed thread for the drive side lockring.
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