Tom, sorry we missed you. Rick & I had walked over to your tent & bike, but you were already out snooping around the grounds. If it weren't for starting my new job the next day, I would have stayed thru Wednesday (they had a trainer in from germany & it was my only opportunity to get the training). I was a little concerned about getting the bike home safely with that big rusty fan in the truck, but with Rick's help & strapping material, everything worked out.
I used to have a used bike / repair shop on the side years ago & worked on just about everything (antiques up to the mid-seventies). Over the years I've seen rings that worked their way around the bore and I've seen rings that never moved. Bob said the later cylinders had larger diameter ports & that's why they are more suceptable to catching a ring. As you said, the motors are so scarce, I think it worth the effort to add an extra layer of protection.
I'm still on the fence about upgrading the rod. Listening to Bob, it put the fear in me about throwing a rod & ruining the crankcase, but then later, Jim had the opinion that a thrown rod is not that common (especially in a well maintained motor).
I'd like to see one of Wayne's cranks to see the difference from a stock one. I wonder if his new cranks are "oversized" in the port area to compensate for worn crankcases?
Mike Sal