RC Collar 5 x 8 x 2.5 — Hirobo HI2521061 linkage spacer  [HI2521061]

Linkage collar — 5 x 8 x 2.5

This Hirobo collar is a compact retention component, dimensioned 5 x 8 x 2.5, intended to locate and secure linkage pins and shaft interfaces in helicopter builds. Its purpose is mechanical: to act as a spacer and retaining element where repeatable, compact positioning is required for repairs or initial setup.

Installation notes: check that the collar inner diameter suits your shaft and that the outer diameter fits any receiving bore, push the collar into position on the pin or shaft until it seats, then confirm neighbouring linkages operate freely prior to locking fasteners. Recheck axial alignment to avoid introducing binding in cyclic or pitch linkages.

Tuning role: these collars are handy for removing endplay and fine-tuning control geometry; minute adjustments in collar placement alter lever arms by fractions of a millimetre, which affects neutral positions and trim precision.