Surge then bog



I am having it surge then bogging. It goes to about 28mph then it will bog down down to 23mph then go back up to 28mph then bog back down again... I cannot seem to break the 28mph barrier.
Fuel starvation...check you filter and the in tank screen. also a slight adjustment to the float may help.
It was not getting a complete spark I guess.. I had a really loud bang then the motor stopped running... The spark plug connector thing from the CDI to the spark plug blew apart.. I had to repair it now I am able to do 35mph.