Mark XX vs Mark XVIII, opinions?

[Caboose]

Got a V7F XX and can't screw the crown "tight", is this a common issue or just bad luck?

Is the crown cross threaded potentially? You'd know if it is tough to screw and unscrew the crown.

Is the stem too long and you can't screw the crown down fully? You'd know if you can't screw down the crown all the way.

 

[nico79]

Perhaps the stem is to long. I can screw it nearly tight, but then it gets loose. Perhaps the the thread is damaged or worn out?

 

[Caboose]

Perhaps the stem is to long. I can screw it nearly tight, but then it gets loose. Perhaps the the thread is damaged or worn out?

If you are screwing it down and then it pops out, if could be bad crown threads, but in my experience press fit crown tubes slide out sometimes. Unsure if this is press fit however. Can you send us a picture of the defect when it pops out close up on the crown tube?