I took this picture of this front 52 head to show you the hole in the intake port. Somebody put a helicoil in the top of the head for the pan covers and drilled too deep. There is no way this bike would have ever idled correctly with a .186 hole in the intake port. Check out how deeply the seats were cut in the head. They were able to get a mediocre area for the valve to seat, but the thing that they over looked was the valve protrusion. The upper valve collars were hitting the pan covers, plus the spring tension was off. These seats are getting replaced!
Here is Ed's 55 panhead, we are trying to get it off for paint this week. It will be hollywood green, so that is pretty neat.