Wes, You must not have watched this year's Tour de France! Someone (Ibanesto?) had a tire roll off the rim due to the heat right in front of the eventual winner!! Luckily, Mr. Armstrong trains in Cyclocross during the off season, and made a "detour" off the road and into/across a culvert. It was scary to watch. One minute they're cooking along and the next moment, the lead rider is on the ground with broken bones! Richard (give me clinchers) Reno Green Bay, WI.