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This question was asked a few years ago and the answer, while very useful, is not resulting in a complete solve for me.

Here is the previous thread - Tightening bottom bracket prevents crank spindle from turning

I am having a very similar issue. I have 68mm shell and a cartridge BB that therefore requires a spacer on the drive side. With the spacer installed there is quite a lot of friction in the spindle when I tighten up the BB.

I know that I should be able to tighten both sides fully, so my question is - is a certain amount of friction expected or should the spindle spin totally freely. Any advice would be much appreciated.

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  • Is this a new cartridge BB you're installing? Sometimes you get a bad one.
    – Armand
    Jul 17 at 14:41
  • I've noticed that while previous generation Shimano cartridge bottom brackets tended to be made as "universal" 68/73mm shell width versions, with 2.5mm spacers installed in 68mm shells on both sides to pad them to 73mm, the most recent generation of BBs is single-width specific. What model BB are you using, and are you using 0, 1 or 2 spacers?
    – Armand
    Jul 17 at 14:48
  • It's not a new one, it's the current one which was I was re-greasing. Tbh the axle doesn't spin super freely even when the BB is totally out of the shell, seems like there might be some dirt or grit inside the cartridge. It's the only one I've used on this bike and I've had for 6/7 years. I'm only using 1 spacer atm, 2 means the chain rings are too far out to line up with the front derailleur, and I can adjust it cos the limit screw heads are totally worn. Time for some new parts maybe.
    – Ben Larthe
    Jul 17 at 18:00
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    please name the brand and model of bottom bracket
    – JoeK
    Jul 17 at 18:57
  • It's a power pro 7420
    – Ben Larthe
    Jul 18 at 10:48
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The inconvenient truth is that most of the time when a bike is having issues like this, facing and chasing the shell solves everything, revealing that shell tolerance was the problem all along. If it doesn't, you can then and only then know it's a part quality issue. (Even then, "know" is overstating, because it's possible for a shell to be bad enough that piloted taps can't fix it. But that is an outlier situation.)

Some none-zero amount of added friction when tightened is normal. It wouldn't be reasonable to expect it to be looser or literally unaffected. But the effect is usually negligible for a good BB in a good shell.

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  • My frame is an old steel one and there is no facing to be done (looks as though someone already did it prior to me owning the bike). I will try chasing and see if that helps, thanks.
    – Ben Larthe
    Jul 18 at 11:10

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