Then someone at Kawasaki is not torquing the screw very well even with the Loctite applied. As nearly every engine that has a bent push rod here has these studs broken off. Should not happen if the screw torque alone was preventing bracket from twisting out of place.
Can't comment on the history of the rocker adjustment problem. Anything possible. Just now you got to replaced the parts.
Bare minimum is the 92153-7100 specialized bolt and the 312AA-0600 6mm nut. Then you got to inspect the bracket 11055-7009 and the collar 92152-1689.
And sure the tiny stud that prevent the bracket from rotating is not broken off. If it is then it a complete head replacement.
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