Eagle/Freya/EX/SX 5mm Ball Radius Pin for Linkages - HI0404532 by HIROBO  [HI0404532]

Precision 5mm ball radius pin for control linkages

This 5mm ball radius pin is an RC-scale replacement part specified for common HIROBO helicopter assemblies used across Eagle, Freya, EX and SX platforms. It functions as a pivot pin for ball-head linkages and control joints, creating the mechanical interface between ball cups and linkage rods in the rotor and control systems.

Fit this pin whenever a loose or damaged ball connection is causing slop or uneven control inputs. It is intended as a direct replacement within the shared parts group for the named platforms, and should be installed using the existing ball-head and retaining hardware already present in the linkage assembly.

Installation notes: remove the linkage assembly from the airframe to access the ball joint, inspect mating surfaces for signs of wear, and pass the pin through the ball-head and linkage eye before securing any retaining clips or fasteners. For best results, confirm full travel clearance and smooth articulation, and renew any mating cups or bearings that show excessive wear.

Tuning role: installing a fresh ball radius pin tightens the joint, helping to preserve predictable cyclic and pitch authority; small changes at the ball joint can alter control feel, so make measured adjustments and recheck trim after fitting.