I was riding along quite happily on my speedfight 100 earlier and all of a sudden the rear wheel seized. The engine still works fine but didn't have the power to turn the real wheel although I can just about turn it myself. I checked the rear break but that's not the problem. I couldn't push it home so I rang the breakdown service who picked it up after over 2 hours wait and dropped it back at mine but he didn't have a clue - was more concerned about getting home for his tea. Any ideas gratefully received. Hope it's not going to be a major expense to fix.