Can anyone help me understand this sequence of events? I can't tell what caused what. 1. Had 700 x 30 Ritchey Tom Slicks on Specialzed Crossroads rims. No problems. 2. Bought Nashbar Comfort Road tires, marked 700 x 32. Installed them and discovered they actually measured 700 x 28. VERY difficult to install! 3. Rode for 2 weeks. No problems except I had to add air every few days. 4. Tonight: Added air. Rode 2 miles, including some turns. Noticed what Sheldon Brown calls "wallowing" upon cornering. 5. Then heard front brakes rubbing. Rim appeared to be suddenly out of alignment. 6. Saw that tire had popped off rim. What do you think caused the tire to come off?