Since around at least 1980 most Motorcycles have used 2RS bearings.This stands for 2 sided sealed.They are not motorcycle specific and are in fact industrial engineering bearings.
Only buy them from a trusted source as there are FAKES around.
As for brands Koyo/NTN/All Balls/SKF are a common good brands I've used.
I wouldn't use open bearings any more.
HTH
