I just got my Mini Fastrak yesterday (mulching kit installed). After mowing for just one hour in relatively short grass, the blade drive belt fell off. It was so tattered that I had a hard time finding the V to put it back on. After putting it back on and attaching the spring, I looked in back where the belt attaches to the motor. The belt typically passes in between the two transmission casings, but I noticed that on the right side, it was hitting the transmission casing, and had actually carved a notch of about 1/16" in the casing from having rubbed against it while running. I'll be taking it back to the dealer tomorrow, but I just wanted a heads-up as to what could possibly cause this problem. A neighbor said that I should insist on a new mower, because it's hard to tell if this could have shaken the spindles, pulleys, or transmission case too much. Any ideas?