73mm square taper bottom bracket into 68mm shell
#1
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73mm square taper bottom bracket into 68mm shell
So, I installed a 73mm square taper bottom bracket into a 68mm shell. The drive side is fully in and good. But on the left side, it has a 2mm thread space outside. Is there a solution for this or simply let it go and it will not have any effect?
#2
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In order to install a 73mm bottom bracket in a 68mm shell, you need a 2.5mm spacer on the drive side. Without the spacer, the spindle will be off center
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#4
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You could source a spindle with the correct spacing for a 68mm.
That would be the only difference, unless this is a cartridge bb,
rusty
That would be the only difference, unless this is a cartridge bb,
rusty
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#8
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If the chainline is problematic, it's possible that a 2.5mm spacer would "correct" the situation. Although given that the OP just shoved a 73mm bracket into a 68mm frame, I'd want to know more details before assuming that the spindle length is "correct" for the drivetrain in the first place.
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Given that a Shimano square taper BB is about fifteen bucks, I can't really fathom how this is even a question.
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Still 3 times the cost of a spacer.
#13
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So a kludge rather than the correct part? I would rather spend the tiny bit extra and get the correct part. I could probably sell the 73mm BB and recoup some of the money I spent on the correct part. We aren't talking $100s here then I might say try a spacer but when you can do it correctly for not a whole ton of money and it will probably be a better more long lasting and reliable solution.
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73mm BB in 68mm shell. Is there any legitimate reason someone would want to do this? Move the chainline maybe? Can't figure it....
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So a kludge rather than the correct part? I would rather spend the tiny bit extra and get the correct part. I could probably sell the 73mm BB and recoup some of the money I spent on the correct part. We aren't talking $100s here then I might say try a spacer but when you can do it correctly for not a whole ton of money and it will probably be a better more long lasting and reliable solution.
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#17
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My Phil Wood,SKF and IRD Defiant bottom brackets didn't come with spacers. I just ordered the correct sizes for the correct shell width. Of course I am talking square taper as you are talking probably external BBs which do sometimes come with spacers but I have never needed to use those, sometimes for the cranks yes but never on the actual threaded part.
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OK, well the OP now has choices. He can go to his LBS today and pick up a spacer for $5 or he can order a new BB from Jenson for $22 shipped and wait 5 days for it to accomplish the same thing.
I know what I would do, but that's just me.
FWIW, I've run into the exact same situation as the OP (had a 73mm ST BB and a 68mm shell, and I used a spacer. Worked fine for years until I got rid of the frame.
I know what I would do, but that's just me.
FWIW, I've run into the exact same situation as the OP (had a 73mm ST BB and a 68mm shell, and I used a spacer. Worked fine for years until I got rid of the frame.