Z4-forum.com

Is it press in or a cartridge type?

Good question. I was going to look this up because i want to replace the back plate, but to do it properly need to pull of the wheel hub.
So i thought might as well replace bearing.

Looks like it's pressed into trailing arm.
https://www.realoem.com/bmw/enUS/partgr ... _23i&mg=33

For the only bearing I've ever needed to do on a BM I simply got a decent second hand hub and swapped the whole thing to avoid downtime and the hassle of getting the job to someone with a press.