Shimano crankset with FSA bottom bracket? I have just taken off an FSA crankset from my Orbea Avant M30. The bottom bracket is a BB 86/92. I would like to replace with a Shimano crankset, an Ultegra or 105. Do I need to change the BB to a Shimano or can I use the existing one? It seems to be in good nick.
Thanks
If you have the FSA MegaExo crankset it should have a 19mm axle diameter. The Shimano Ultegra FC-R8000 has a 24mm axle. Measure your current crankset’s diameter but you’ll probably need a new bottom bracket for the 24mm axle.

If you’ve ridden a considerable distance (something like >7Mm) on your current bearings it doesn’t really hurt to replace this 10€ part in any case.