Originally Posted by DannoXYZ
Due to the gap in the threads, when you tighten the lockring, it will actually pull the cup outwards slightly, thus opening up some clearance.
Unless, of course, in the process of tightening the lockring, you also turn the adjustable cup a little too. You need to play with it all a little bit and figure out where you want the cup to end up so that tightening the ring will tighten it up but also put it outward...just so.