This may be to obvious but my son`s 01 blast quit on him on the road. After checking spark,fuses,fuel level,gas cap-vent I was about to rip the carb off. when I grabbed the air box I thought it did`nt feel right. Well guess what?
The carb had popped out of Das boot. Rebooted so to speak and lo and behold, the bike fired right up.
Hope this helps. This is what happens when you put a big ol carb on a big ol single, sometimes.