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On a scale of 1 to Ghetto, where am I at with a 68mm BB in a 73mm shell?

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On a scale of 1 to Ghetto, where am I at with a 68mm BB in a 73mm shell?

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Old 09-03-23, 05:01 AM
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brokewheelspoke
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On a scale of 1 to Ghetto, where am I at with a 68mm BB in a 73mm shell?

Was going to use a 113/68 BB I had on a bike I just picked up, but then noticed it had a 73mm shell. As it happened, I had a 118/68 also, so I used that along with the non-drive side cup from the original 73. Seems to fit, crank arms seem even on both sides, chainline seems within reason. Am I missing anything? Is this an OK thing to do? Will swap it out if ppl think it's a bad idea.
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Old 09-03-23, 05:20 AM
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wheelreason
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Eastern Parkway near the border of Brownsville and East New York...
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Old 09-03-23, 08:56 AM
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If it's your bike and it works well enough, then leave it if that's what you want. If you give the bike to someone else, just let them know about it so they don't start a thread here saying they can't find a BB that matches the one they just took out of their bike.

If it gives you issues soon then you'll know whether you should have spent a few dollars to get the correct BB.
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Old 09-03-23, 08:59 AM
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Steel Charlie
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BB's are really cheap
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Old 09-03-23, 10:27 AM
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33rd street in hoboken ? Near the corner of Heart Attack and Vine ?

seriously you are going to find that the adjustable cup will be inside the BB and there's no thread left for the lock ring.

what kind of bike do you have with a 73mm BB? Unless its a vintage Cinelli, I'd suggest you face the BB down to 68mm.

/markp
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Old 09-03-23, 12:28 PM
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Are the parts from the same brand? Are the bearings seated correctly on the spindle?

The OP's question is somewhat meaningless without more information.
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Old 09-03-23, 12:32 PM
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Originally Posted by mpetry912
33rd street in hoboken ? Near the corner of Heart Attack and Vine ?

seriously you are going to find that the adjustable cup will be inside the BB and there's no thread left for the lock ring.

what kind of bike do you have with a 73mm BB? Unless its a vintage Cinelli, I'd suggest you face the BB down to 68mm.

/markp
Many mountain bike frames have a 73mm BB shell. I would not recommend facing one down to 68mm when the proper size is readily available.
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Old 09-03-23, 12:56 PM
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Originally Posted by mpetry912
what kind of bike do you have with a 73mm BB?
/markp
Regarding threaded bb shells, there have been about as many mountain bikes made in the last 25-30 years that have a 73mm shell as a 68mm shell.
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Old 09-03-23, 01:51 PM
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Originally Posted by bboy314
Many mountain bike frames have a 73mm BB shell. I would not recommend facing one down to 68mm when the proper size is readily available.
I had not really thought about that so I do stand corrected. and you're right there are 73mm cartridge BBs

/markp
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Old 09-03-23, 02:23 PM
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juvela
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-----

a seventy-three mm shell is suggestive of a machine which came from the factory fitted with a Thun pattern chainset

the other possibility is that it came with a seventy-four mm shell which has been faced down

in addition to Cino the seventy-four size was employed by some other oytoy producers BITD


-----


-----
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Old 09-03-23, 05:44 PM
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Originally Posted by juvela
-----

a seventy-three mm shell is suggestive of a machine which came from the factory fitted with a Thun pattern chainset

the other possibility is that it came with a seventy-four mm shell which has been faced down

in addition to Cino the seventy-four size was employed by some other oytoy producers BITD


-----


-----
Nope, standard MTB shell width. Happened at the same time MTBs went to 135mm rear hub spacing.
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Old 09-04-23, 03:49 AM
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Originally Posted by Iride01
If it's your bike and it works well enough, then leave it if that's what you want. If you give the bike to someone else, just let them know about it so they don't start a thread here saying they can't find a BB that matches the one they just took out of their bike.

If it gives you issues soon then you'll know whether you should have spent a few dollars to get the correct BB.
Seems good so far, nothing loose or squeaky.

Originally Posted by Kontact
Are the parts from the same brand? Are the bearings seated correctly on the spindle?

The OP's question is somewhat meaningless without more information.
Bearings on spindle? It's a sealed cartridge. Is anyone actually using anything besides sealed these days?
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Old 09-04-23, 09:57 AM
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Originally Posted by brokewheelspoke
Bearings on spindle? It's a sealed cartridge. Is anyone actually using anything besides sealed these days?
Pardon. I meant are the bearings correctly seated in the cup?
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Old 09-04-23, 10:06 AM
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$16 for the right one.

​​​​​​https://www.benscycle.com/shimano-bb...p?idsku=682660
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