Hirobo HI2500069 ball bearing 5 x 11 x 3 mm (open type), 2 pcs  [HI2500069]

Ball bearing for RC helicopters

This HIROBO HI2500069 ball bearing is an RC-scale spare part supplied in a two-piece set, specified as an open type with dimensions 5 x 11 x 3 mm. It serves as a compact running element for small rotating assemblies found in model helicopters and similar small RC systems.

Open type bearings offer easier inspection and relubrication compared with sealed units, which can be useful during assembly checks or tuning sessions. As a simple mechanical component, this bearing helps maintain alignment between shafts and rotating parts while reducing friction when correctly installed.

Installation tips:

• Ensure the bore and shaft seating are clean and free from burrs before pressing the bearing into place.
• Press the bearing by its outer race when fitting into housings, and avoid applying force to the inner race to prevent damage.
• Use light bearing lubricant suitable for model applications if smoothness needs improvement during setup or after cleaning.

Role in tuning and maintenance:

When replacing small bearings like this HI2500069 unit, check surrounding components such as pinions, spur gears, and rotor linkages for wear, since bearing play can affect gear mesh and rotor tracking. Swapping worn bearings for fresh units can restore smoother rotation and reduce unwanted vibration in RC models.