Got a 73mm BB shell (Orange 5) and a Truvativ Stylo crank…

Just tried for a frustrating hour to fit a replacement external BB to find that when I tighten the crank up it gets to a point where the crank can’t tighten any further (as the non-drive side bearing is up to the ridge on the crank spline) resulting in a gap between the drive side bearing and the end of the crank spindle and some play.

I haven’t used any spacers as it says don’t if the BB shell is 73mm wide.

They are both SRAM GXP BB’s.
The old BB says BSA 42-08
The new BB says BSA 25-30

I think those numbers are the torque.

What’s wrong?

Pic if it might help – you can clearly see the gap between the crank and bearing

Hmmm, am I being thick here or something? I’ve just put the old BB back on and that had the same gap – rode that without noticing for 9 months. Maybe it’s supposed to be like that although it seems odd that there isn’t a spacer or something (I could have lost it without realising some time ago if there was).

It’s supposed to be like that, the axle “floats” in the drive side bearing, and is held in place by clamping the other bearing between the step and the crank, it stops the ham-fisted from preloading the bearings as can happen with other types.Not sure why you have play though.

Yeah the play is odd, although having put it all back together (yet again) the play is very minimal so maybe this is just natural tolerance. Everything spins fine so, given your explanation, I’m happy now 🙂

Thanks.