Spark plug is not the problem. If it only rune with choke on. you have a dirty carb. You say the carb is new. Doesnt matter. you probably have dirty gas tank or crap in fuel line and you already Dirtied the new carb.
You need to remove the fuel bowl from the carb, up inside the center is a brass jet. Remove the jet clean it and reinstall. This should solve your problem.
But since this is a new carb already plugged, Clean the Fuel system, tank and fuel line. See if you can install a fuel filter. There is very little room on a stock clone to add a filter
