First time out Kart cranked and ran for about 5 minutes. Shut off and will not crank back. Starter turns over, but won't crank. Has fire to the plug, gas in the bowl.

 

"Starter turns over, but won't crank"

Another one! "Wont crank" literally means won't turn over on the starter, please don't use that expression, particularly when you don't mean it.

Rant over, you probably have dirt in the carb, clean the float bowl and jets out with compressed air and try again.