Didn't happen. I was dressed and ready to go but, walked outside to another flat. This with a new (loaner) wheel, tube, and tire. My wheel is still in the shop awaiting the installation of a new axle. I was running late and didn't even investigate this one, my guess is that the tube's valve stem was cut by the wheel as the shop put a presta valve in a rim drilled for schrader-the valve stem was noticably crooked and was probably cut. Monday was my first day back on the bike after a week's vacation and, after numerous flats (4 or 5) in the weeks preceding vacation. So, I can't seem to win, I might take the week off while I re-evaluate the situation, it's gotten too frustrating at this point.