Precision 5 x 8 x 2.5 Collar Hirobo HI2521061 for RC linkages  [HI2521061]

Precision spacer collar

This Hirobo collar is a compact RC retention item measuring 5 x 8 x 2.5 that locates and secures linkage pins and shaft interfaces in helicopter assemblies. Its function is mechanical, acting as a spacer and retainer to deliver compact, repeatable positioning during setup or repair operations.

Installation notes: verify the collar inner diameter fits the shaft and the outer diameter matches any receiving bore, push the collar into place on the shaft or pin until it sits evenly, and confirm neighbouring linkages operate without restriction before locking any fasteners. Check axial alignment after fitting to avoid inducing binding in cyclic or pitch linkages.

Tuning role: collars of this size are commonly used to remove endplay and fine-tune control geometry; minute changes in collar position will alter lever lengths by fractions of a millimetre, which affects neutral trim accuracy.