While doing a bike race in Texas (`No Country for Old Men') last weekend I went over a very rough cattle guard. The front tire hit so hard that it `pinched' against the rim of the wheel and blew the tube. The wheel rim, then, slipped on the rough chip seal and the bike went down hard, sliding about 20 feet across the road into the dirt and rock. One of the `exciting' aspects of a race. We fixed the flat and I continued on. Though it looks ugly it is superficial skin damage and bruising.