Need help for bottom bracket size.
01-16-14, 02:45 PM
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Need help for bottom bracket size.
I just receive my Colnago Sprint and found out that I can't ride it because the chainring touch the frame. When open, I see that the spindle is 68-ss when my BB is 70mm. Is it the reason the chainring touch the frame? I would say 2mm different only cause the left side cup to go deeper inside instead.
Anyone have experience with this problem? I worry that the crank hole get loose and cause the crank to go deeper as the bolt is tighten.
Your help is appreciated.
Anyone have experience with this problem? I worry that the crank hole get loose and cause the crank to go deeper as the bolt is tighten.
Your help is appreciated.
01-16-14, 03:09 PM
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It seems you need a longer spindle anyhow, might as well get one the right size. As to whether the 2 mm is relevant: as long as you can fit the lock ring you're OK, I think.
01-16-14, 04:51 PM
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What??? Only 2 wheels?
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The position of the chainring, i.e. the chain line, is determined by the shape of the spider as well as the BB width. And the potentially bearing cups. Usually the required spindle length is specified for the particular crank, not the BB width per se. If the bearing cups can be adjusted okay then, as nf says, the BB width isn't necessarily a problem. But the overall length is a different spec.
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01-16-14, 05:09 PM
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Ok this is going to be fun.. you really need to determine if you have an italian or english BB
The 68 on the spindle indicates that this is for a 68mm or english BB
you said you bottom bracket is 70 mm which is most likely an italian BB
the 2 mm is important.
You need to put up some pics (bb, Spindle, crank, clearance issue) Measure the spindle, and say what type of crankset you have.
not enough information to determine one way or the other, but it sounds like you have a spindle that does not match the bb.
The 68 on the spindle indicates that this is for a 68mm or english BB
you said you bottom bracket is 70 mm which is most likely an italian BB
the 2 mm is important.
You need to put up some pics (bb, Spindle, crank, clearance issue) Measure the spindle, and say what type of crankset you have.
not enough information to determine one way or the other, but it sounds like you have a spindle that does not match the bb.
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01-16-14, 05:21 PM
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Ok this is going to be fun.. you really need to determine if you have an italian or english BB
The 68 on the spindle indicates that this is for a 68mm or english BB
you said you bottom bracket is 70 mm which is most likely an italian BB
the 2 mm is important.
You need to put up some pics (bb, Spindle, crank, clearance issue) Measure the spindle, and say what type of crankset you have.
not enough information to determine one way or the other, but it sounds like you have a spindle that does not match the bb.
The 68 on the spindle indicates that this is for a 68mm or english BB
you said you bottom bracket is 70 mm which is most likely an italian BB
the 2 mm is important.
You need to put up some pics (bb, Spindle, crank, clearance issue) Measure the spindle, and say what type of crankset you have.
not enough information to determine one way or the other, but it sounds like you have a spindle that does not match the bb.
There might also be a mismatch of generations of Campagnolo crank arms and the spindle which has already been Identified as wrong.
An image of the back side of the drive side crank arm showing the code and appearance of the spider adjacent to the spindle port will also be reasonable.
01-16-14, 06:51 PM
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If it is a true Colnago, then it better be Italian thread. Unless it is just a Colnago by graphics...
There might also be a mismatch of generations of Campagnolo crank arms and the spindle which has already been Identified as wrong.
An image of the back side of the drive side crank arm showing the code and appearance of the spider adjacent to the spindle port will also be reasonable.
There might also be a mismatch of generations of Campagnolo crank arms and the spindle which has already been Identified as wrong.
An image of the back side of the drive side crank arm showing the code and appearance of the spider adjacent to the spindle port will also be reasonable.
https://00eda5d.netsolhost.com/bottom.html
The spindle could be the older generation when the crank is 1982 so that why the cranks goes deeper inside. Hope this is true. At least I don't have problem with the crank which is more expensive to remediate the problem.
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