[Biebs]

On the oil level do not fill to top mark my 74 R75/6 runs at oil level about middle of dip stick if I fill to top mark on dip stick it will burn off the extra oil and settle at the middle of stick and stay there forever like that spot.

So if you are fill crankcase to much you will burn off /have oil coming of breather. Black pistons show you are burning oil not a good thing.