Yokomo/Associated Diaphragm Shock Cap Set for 1/10 RC Dampers - YOKYS8D Yokomo  [YOKYS8D]

Sealed diaphragm cap overview

This diaphragm shock cap set is a damper component for Yokomo and Associated shock bodies. The flexible diaphragm replaces a traditional solid cap to help keep internal pressure stable, reduce oil aeration, and stabilize damping behavior during repeated compressions.

Compatibility is limited to the brands listed in the product name, so verify your shock body design before fitting these caps. The diaphragm isolates shock oil from direct air contact, which cuts down on foam and keeps damping more consistent over longer runs.

Installation is straightforward for someone familiar with dampers: remove the shock from the car, contain or drain oil as needed, remove the original cap, seat the diaphragm evenly against the shock body, and reassemble while checking for proper seating and even tightening to avoid pinching. Cycle the shock slowly after assembly to confirm there are no leaks and that movement is smooth.

Use the diaphragm cap alongside spring and oil adjustments rather than as a tuning substitute; it preserves oil condition and repeatability, which is especially useful on high-speed or extended-run tracks.