MOPED ARMY

How does one go about fixing this? The carburetor looks like someone replaced the float and float pin. Could they have put jets on that are too big? It fouls out the spark plug making it all black within 5-50 miles. It only idles with the throttle set screw all the way to the right. The throttle response from idle takes about 5-10 seconds before the wheel spins. How do I pull the jets off to tell? Its getting maybe 10mpg (no big bore or any crap like that I just replaced the piston with a stock 40mm) Also if I turn the fuel valve off the bike starts spinning its tire like its being throttled but for like 5 seconds it runs good with an instant throttle response. I checked out the reeds to see what the deal was and they don't look cracked and they're fairly springy. The bike has 0 issues starting even with the auto choke disconnected. I tried ordering a revolution carb but it literally won't stop pissing, all the gas that goes in comes out the bottom. If I plug the overflow it just comes out the air filter. I checked and the float seems to work, if I plug the float manually and try to put water in it stops it.