Hirobo HI2500046 Ball Bearing Set 6x12x4 mm, 2 pcs  [HI2500046]

Small-diameter 6x12x4 bearings and their uses

The Hirobo HI2500046 ball bearing comes as a 2-piece replacement intended for routine maintenance of RC helicopter components. It is a compact precision part used where smooth rotary action and minimal friction are needed on small shafts, pinions and gearbox interfaces.

These bearings play a focused role in reducing rotational drag at seating points, supporting both axial and radial loads in common helicopter linkages, and aiding consistent rotor and gear mesh behavior. Properly installed bearings help maintain steady servo response and drivetrain performance during tuning work.

Installation notes: confirm shaft fit and bearing seat tolerances before pressing in, use an appropriate press or carefully applied even force, never strike the race directly, and check endplay and preload per your service manual. Apply a light, suitable lubricant and inspect periodically for wear or corrosion to prolong service life.

Tuning tips: fit bearings in matched pairs when wear is present to preserve balance, listen for grinding or rough rotation as a sign of impending failure, and keep lubrication clean to avoid abrasive wear. For precise gear setups, a bearing seated with minimal axial play helps improve repeatability.