I just heard a silent "pop!" and next thing I knew was that I had a flat tyre. The tube just blew up. I was already on the way to the bicycle shop, but still one mile away. Originally, all I wanted to buy were some new brake pads and look for a new front lamp. Now I have two new tubes, a new tyre, a pair of rim tapes, the brake pads, a new mount for the existing lamp, and not enough time to fit it all this weekend.