One thing I learned the hard way, don't tighten the nut on the valvestem until AFTER you do the inflating, it can cause the tube to pinch and pop

That is the only "flat" I have had so far, I was changing tires and put the same tube back in. oh wait, B/F was changing the tire for me I was watching He still can't make himself put 100# in the tires, I have to put more in them after he is done.