The title is misleading, but when I was scrubbing down the gunk on the (uninstalled) engine today, I thought I found that the cooling ribs on the right side were cracked (right behind the front cover). As I looked closer, they appear to have been machined down. I think the frame ran through there.
So the question is, why? Is the engine slightly off center? Why would it be machined down on one side and not the other?