ceramic bearings for dirt bikes 1,ABEC7 2,High speed 3,End cover:ZZ,RS 4,Noise level:Z1, ... ceramic bearing, hybrid ceramic bearing and full ceramic bearing, the hybrid ceramic bearing has steel inner and outer rings with ceramic balls, as for the full ceramic ... oxide, they are white colored, a ZrO2 ball looks exactly like a pearl. the ceramic material is not stronger than steel, but ...