The tire tread pattern has these half moon indentions. It was along these areas that the tire was failing. The rim was cracked more toward the center than the outside but not right next to a nipple. I recently had a broken spoke replaced...I wonder if they over-tensioned it?? Anyhow, like I said, at least it's under warranty. But I hate getting up early for a group ride, driving to the start and then finding out I can't ride.....urrgh!!!