Yeah I did. Or something similar.
Typical gy6 powered china kart.
They do have a charging system. Not like an alternator on your car but magnets inside the flywheel and a pick up coil. There's a voltage regulator box. It's the one with the heat sink fins.
Easy check to see if it's working.
Check battery voltage with engine off. Should be around 12.5 volts with a good battery.
Start the engine, check voltage at battery. Should be above non running voltage. Like 14 volts or so.
Valve on the carb? Need a bit more than that. Perhaps the choke? Mine has a black plastic handle to actuator it.