I went for my first ride in about 3 weeks this morning. Great day, partly cloudy, mid-30's, no wind. Rode for just a little over an hour then came home and put my bike back down in the basement to keep it out of harms way from the pending x-mas explosion.

About 30m later I took the kids to the pool and the H went his studio, also in the basement, to play for a bit. He called me and said he'd just heard a loud "pow!" and was looking around to see what it was. He figured out it was the tube in my back tire.

These tubes, lbs dude said they were "top of the line" (don't recall the brand), only have about 80 miles on them and I filled them with sealant because I'd been having a string of flats.

What would cause a relatively new tube to explode like that?