High-speed micro motors amplify small variations in bearing geometry, internal clearance, lubrication and installation. Selection should therefore begin with the complete operating profile.
Confirm rotational speed, radial and axial load, shaft and housing fits, temperature, desired acoustic level, duty cycle and expected life. These inputs guide precision, noise grade, clearance and grease selection.
Prototype testing in the actual motor is essential. A bearing that performs well on a bench can behave differently after press fit, rotor balancing and final assembly.