I rebuilt several Enya's in the 60 size and noticed all rubbed real hard. One day I traded for another Enya and the front housing had a spacer on it. The spacer was metal and factory made and guess what yep very little rub, so some engines which include Japan made models are simply designed wrong and they do fix them.
I suspect a crank that is pushed back in the case slightly. Take the carb off and muffler and put it in the oven at 250 for 1/2 hour. Use a towel of glove, put a prop on it and snug it up tight. That will shift all into correct alignment. Turn it over by hand a few times and when cool oil it. I think your problem will be over