3 x 9 x 3 mm Hirobo HI2500070 Ball Bearing Set (Open Type, 2 pcs)  [HI2500070]

Helicopter bearing replacements and pivots

This RC-scale bearing set is made for routine helicopter maintenance and small linkage pivots. Marked as HI2500070, the product includes two open bearings sized 3 x 9 x 3 mm intended for use where low profile and compact housing fitment are required.

These bearings provide rotating support in rotor hubs, swashlink assemblies, control arms and similar small pivots. Before installation, check seating diameter and axial clearance on the hub or linkage to prevent binding and inspect the mating bore for signs of wear or deformation.

For installation, press the bearing evenly into the host bore using a soft drift or a bearing press that contacts the outer race; avoid forcing the inner race. Verify the bearing spins freely after seating. For open bearings, apply light rotary oil only when conditions allow, or schedule regular cleaning and re-lubrication if exposed to contaminants.

Note that this item is intended purely as an accessory for model aircraft and scale components, not for use in full-scale vehicles.