Replacing the GXP BB on Mrs Stoner’s 68mm shell TT frame and following BB instructions Im sure* it says to use the two supplied spacers on a 68mm BB shell.

But it’s obvious that if I do, as I tighten the NDS crank on to the axle that it’s loading the bearings. If I remove the spacers, and tighten the crank to it’s stop, the bearings are unloaded and there is no play – i.e. it all fits perfectly.

Do I have a GXP crank that will ONLY fit on a 68mm shell with no spacers? Is it a special crank? As it would appear there’s no way it could fit to a 73mm shell as the axle would be too short.

* the graphics are hardly definitive

Road frames / bbs don’t use spacers (they are all 68mm if BSA threaded)

Road frames

or you mean road cranks are designed around 68mm shells only (the ones with bonded axles anyway). I never knew that.

school day today. Thanks

It’s sort of because road is normalised around 130mm back end. Even though all disc road bikes use 135/142 back ends which everyone seems to ignore.

I had exactly the same problem with my Planet X XLS! Strangely this works fine with one spacer but if you used two, everything seized.
I’ll be watching the thread with interest.

[video]https://www.youtube.com/watch?v=NufgDt2zwXk[/video]

AD did you try it with no spacers?

I did – no spacers seemed not to allow the crank to be drawn far enough onto the axle to touch the bearings. It really seems to need a single spacer.

Since one spacer worked, despite all the diagrams suggesting that it shouldn’t, I have ran it like that for the last six months without any problem. Spacer is installed on NDS purely to improve the chain line (it is a 1×11 set up).

how odd