kevlar belt in 1 day and now blended?

i put a new belt in my speedfight 100cc 98 and it was going great i mean better than ever some matie over took me so i thought id give him a run for his money i was proper on him doin maybe 60-5 ish then bang the back wheel locked up and left a nice scar on the road and had to walk home everything was put together right and was checked before i went out on it what could have this