Loss of tire pressure from AutoX?

[ausgezeichnet]

I ran my first AutoX a few weekends ago in Hershey. Checked my tire pressure at the beginning and after the first run. All was fine. Made 3 more runs and then came home and parked it in the garage. A few days later I noticed the the back rear tire pressure was really low. Only 10 lbs of pressure. A few days later still 10 lbs of pressure. Took it to the tire store to check for leaks. There were no leaks anywhere. Is it possible the tire separated from the rim enough to let 26lbs of pressure out during one of AutoX runs?