Various bearings with different tolerances to test.
Please note that these are untested.
I will let you know my findings :).
225 = 0.255mm between Rollers and Races etc.
0.3mm Conical - Doesn't work rollers fall out.
0.25mm Conical - rollers do not fall out but rotate onto side. Works ok but more rollers needed with a smaller tolerance.
I'm a noob at bearing design for 3D printing so comments welcome.