Can you post links or pics of the HD Pan Am failures?As an example: the new HD Pan America has already had multiple reports of broken engine cases from taking a hard landing
Could the engine case breakages be from landing the oil sumps on a rock that was too tall, ground clearance totally consumed by too much 'flight time' and simply not enough space between skid-plate and engine?
Our own KLR engines are 'set-down' between the lower frame rails enough that the oem oil drain plug & one engine case assembly bolt protrude below the frame rails. With the oem plastic skid-plate & even several brands of aluminum skid-plates, rock damage still occurs. I install stiff rubber cushions between KLR frame rails & aluminum skid-plates for added protection space.
I find it kinda' hard to believe that the HD Pan Am engine mounts broke because of being a stressed member of the frame. But I would rather have frame rails/skid rails down there supporting a skid-plate.