These pocket bike engines have extremely tiny Jets if even the most minuscule amount of dirt gets into the tank you will have this exact problem that you described running like crap with the choke half on then you let it sit for a while and the dirt floats out from under the jet and it runs for a minute or two and then it sucks that same bit of dirt back in and clogs and your back to the same problem.
You're going to need to take the carburetor off and clean it out and shine a flashlight through the jet and make sure it's clear be extremely gentle with the delicate carburetor parts and don't try to shove anything metal throw the jet...
I also recommend cleaning the tank replacing the fuel filter and line with quality stuff from the auto parts store
Faster then a speeding E Revo
Last edited by MrKitty; 05-02-2020 at 04:36 PM.