RE: Difficulty trimming for yaw with a CX2.
Been there Bob, And I've done that exact thing. The plastic bearing holder does not run true in some cases. Mine had that issue and I replaced the plastic holder with the Eflight aluminum replacement. Problem solved.
Hat's off to your "sleuthery". I do believe you will have a winner with the new part installed. Then you can get back to eating and sleeping and such.
And of course I'd appreciate you posting the results.
Curious minds need to know.
Soloboss