Shimano UN26 Cartridge BB assembled wrong?
#1
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Shimano UN26 Cartridge BB assembled wrong?
I have this Shimano square taper UN26 cartridge bottom bracket that I think might have been assembled wrong.
It's the drive side part that has me thinking that. The flats of the square taper end BELOW the drive side cup. Thus when I go to put a crank arm on it the crankarm goes all the way to the cup. Interestingly enough the exact same crankarm only goes partway onto the the non-rive side spindle.
Here are two images of the bottom bracket that I hope shows the drive side spindle okay for analysis by you folks.
So, am I correct in thinking that this unit was wrongly assembled?
Thanks and cheers
It's the drive side part that has me thinking that. The flats of the square taper end BELOW the drive side cup. Thus when I go to put a crank arm on it the crankarm goes all the way to the cup. Interestingly enough the exact same crankarm only goes partway onto the the non-rive side spindle.
Here are two images of the bottom bracket that I hope shows the drive side spindle okay for analysis by you folks.
So, am I correct in thinking that this unit was wrongly assembled?
Thanks and cheers
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Is the drive side cup seated all the way onto the cartridge body? I looks like it can be slid on further.
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I don't think you understood what I was asking. You said; " The flats of the square taper end BELOW the drive side cup." I asked if that drive side cup pushed down over the cylindrical body as far as it will go? If not, it will interfere with the crank arm as you noted.
Some Shimano cartridge bottom brackets have the drive side cup as an integral part of the cartridge body and the NDS cup is a slip fit over the NDS end. Others have both cups as slip fits over the cartridge body. Which type is yours as I can't be sure from the photos?
Some Shimano cartridge bottom brackets have the drive side cup as an integral part of the cartridge body and the NDS cup is a slip fit over the NDS end. Others have both cups as slip fits over the cartridge body. Which type is yours as I can't be sure from the photos?
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I agree with HillRider that the DS cup isn't quite driven down as far as it will go. It looks to be a separate piece from the photo.
I would take the correct diameter socket, put it over, and try tapping it down.
At minimum measure where 73mm falls from the DS cup edge and see if it seems "too long"
I would take the correct diameter socket, put it over, and try tapping it down.
At minimum measure where 73mm falls from the DS cup edge and see if it seems "too long"
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I see a BB for a 73mm width shell with a 110mm spindle. That's a pretty off-the-wall setup. What kind of bike and crankset is this for?
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I've never seen another cartridge bb like this one.
Cheers
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Here is a pic of a 103mm spindle and you can also see the flats are under the shells.
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Thanks all and especially bluehills3149 for the image that shows this is not a wrongly assembled bottom bracket.
Cheers
Cheers
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I have no idea what bike that cartridge bb was intended for. I was going to use it on a single speed. The drive side cup looks to be integral to the shell. If I had a big enough vice I'd try using it and spacers to push the non-drive side part of the spindle further towards th right side.
I've never seen another cartridge bb like this one.
Cheers
I've never seen another cartridge bb like this one.
Cheers
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Cheers
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I'm building a couple of bikes and using parts for them from my scrap boxes. I was surprised when the crank arm on this bottom bracket went right to the end of the taper on the drive side but not on the non-drive side. I 'll be using different bottom brackets on those two builds.
Cheers
Cheers
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