The only thing that can bend it is water in the cylinder. It didn't run good on my last run out, but it didn't run good for a while because of the cam and the valves not opening all the way. The first thought was the frog hole, but it ran fine and certainly couldn't have lasted that long. They cleanness of the cylinder says it must be recent. I had been pulling trees down and out with the winch around the house and yard last summer/fall. Dropping engine off this morning at machine shop, so he wants to look at head gasket, the bolts didn't crack when loosening that corner like they did all across the other side on the head. Maybe it leaked in? Not that many miles on the engine, but with all that cam lobe metal traveling around, the crank bearings are worn too.