So; my back tire likes to lose air. No biggie since it takes awhile. Well Due to weather and work I spent a few days on the indoor trainer, had two days off then go to get in a work out and the tire is dead flat. It had been holding air for at least two weeks. I go to pump it up and all it does is hiss. Just found it funny that it could be fine one day and have a hole in the tube two days later with no use.