Bike keeps dying

[Alexmeow]

My bike starts off going about 14 mph and shaking then quickly dies down to about 4mph still shaking during a quick ride around the block or dies completely and I have to pedal to keep the engine running I check it after and the carb is flooding but there was never a problem with the carb before and everything is tight as can be what could be the problem?

 

[crassius]

with motor cooled down, grab top bar of frame behind gas tank and top of motor with other hand - if you pull hard on motor and it does not move at all, then I'd look for a crack in the frame

 

[bakaneko]

did you try hitting the carb bowl hard with a heavy screwdriver? the knocking could get it working again. but there could be something stuck in the carb from the gas tank. do you have a gas line filter too?