A few members here have given suggestions that have helped them, run the oil level at about half, instead of at the full level .
I tried this method, remove the crankcase breather valve, cut a part of a coarse copper pot scrub pad, place it in the houing, but not so tightly that it blocks off air flow .
But, I think if you reposition the intake tube clamp, maybe a light 'skin' of sealant where the tube goes into the carb and run less oil volume, your problem should be solved .