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I'm getting a Surly Crosscheck frame and I'm putting a 2009 campa veloce groupset into it which has the Ultra torque bb. I'm wondering will I need bb spacers? If I do, how do I know the correct size? According to Surly.com:

"Bottom bracket:


68mm wide, standard English threaded 1.37x24t"

and the ultra torque is 68mm right? so it should be fine without them?

Thanks a lot!
 

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Spacer need

olli said:
I'm getting a Surly Crosscheck frame and I'm putting a 2009 campa veloce groupset into it which has the Ultra torque bb. I'm wondering will I need bb spacers? If I do, how do I know the correct size?
You need spacers if, when assembled, your chain line is not correct. Correct chain line means that the center betweent the chainrings lines up with the center of the cassette. If that is the case, then you need a spacer thick enough to move the chainrings to the correct position. In most cases, you will not need to do this, but you won't know until you build the bike.
 

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correction...

Kerry Irons said:
You need spacers if, when assembled, your chain line is not correct. Correct chain line means that the center betweent the chainrings lines up with the center of the cassette. If that is the case, then you need a spacer thick enough to move the chainrings to the correct position. In most cases, you will not need to do this, but you won't know until you build the bike.

With a UT crank the BB width must be a very accurate 67.2-68.8mm in width or the bearing preload will not be correct. Unless the spacer is needed to correct that width, any amount of spacer added to the right side would have to be removed from the left side by facing.

Be sure to remove all of the paint from the BB faces and check the BB width precisely before installing the cups. I go a step further and tighten the cups to contact a .010 inch feeler gage, then use .008-012 gages to be sure that their are no high or low spots. If there are, the the BB shell should be faced.
 

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Kerry Irons said:
You need spacers if, when assembled, your chain line is not correct. Correct chain line means that the center betweent the chainrings lines up with the center of the cassette. If that is the case, then you need a spacer thick enough to move the chainrings to the correct position. In most cases, you will not need to do this, but you won't know until you build the bike.

If a properly installed BB creates a chain line that is not correct within a group made by the same manufacturer, there are only two possibilites:

1) The manufacturer doesn't know what they are doing. (Campy, unlikely)
2) The framebuilder doesn't know what he is doing. (Mass produced, a possibility)

The relationship between the BB, dropouts and centerline of the bicycle is well known and fixed for road bikes.

People fudge this stuff building frankenbike fixies and that's understandable, but a high end group should just fit right straight out of the box.
 
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