CRAN :
I'm not a Huey driver ( hey - anyone out there willing to change that ? ), but R22s suffer in exactly the same way.
From memory, under negative G there will be an uncommanded roll right in a helicopter with an underslung rotor system and counter clockwise rotating main blades. And you probably know this bit but the instinctive left cyclic to counter the roll will reduce the mast-hub clearance even further . . .