Piaggio zip 70cc

Hi does anyone know what’s could cause problem for my piaggio zip I have a 74 jet it’s 70cc malossi etc but it runs fine but when u ride it it missfires and after abir it kills the plug could anyone know whats happinng also gets really hot i qas thinking bigger jet as idk if its not enough fuel but theres is good oil so ye

 

what size and type of carb are you running, and what kind of air filter (std air box or open filter)

 

Im running a standerd carb and air box

 

What year is the bike?
What pipe is on it?
Are the cooling shrouds fitted to the engine?

 

2016 it has leo vince tt pipe its air cooled

 

It sounds to me like the main jet is too large, and its fouling the plug.

 

Yeah, I know it's air cooled, but does the cylinder have the cooling shrouds on it?
The black plastic thing that goes over the barrel and head........It allows the air from the flywheel fan to circulate around the barrel to help with cooling it

This thing: