Apeks ATX 50 harmonic?

[Pao]

I would request a new spring be installed. Your shop will not do it but on MkV and similar firsts that have done this vibration, I have removed the spring, pressed it in a vice to solid height and then shimmed with a thin nylon/mylar shim/washer. Another trick that they will be totally clueless at is to remove the spring, hone both ends of the spring with rouge or grinding compound, polish and reinstall with silicone lubricant coating each spring face. The idea being to improve/increase the surface contact area of the spring flats to the regulator body.

Also make sure the first stage piston O-ring is lubricated (water generally acts as sufficient lubricant, the reason most stop this honking once submerged) with silicone or correct grease.

N

Thanks! I got new springs. I was about to install them when the sound suddenly stopped by itself :shocked2:. Do you hone the mainspring only or both the mainspring and HP valve spring?