80cc not staying on.

[Sgtnergz]

Does anyone know why or what could be the cause of my i0cc motor won't stay on running it just has a sound of dying down, I wanna say it's an air leak somewhere around the head or the bolts ..I say this cuz I seen some oil leak on top of the cylinder head it's mainly around by the spark plug but I'm not sure that's the problem....the head gasket is a copper one motor is not even a month old....I've checked carb, took apart was all clean,.
Idk I thot to use gasket sealer or switch out the gaskets with a newer one I guess.
Any ideas I'm open to anything I can't figure out what else to do to this bike..I have compression and have fuel flowing and everything is tightened up..I have spark ...

 

[LandSpeedRecord]

Double check your head bolts etc. Spark plug gap, fuel, all the normal things. Then pull the case covers and check for oil blowing out around the crank seals. If you have an intake leak the idle will race so you would know that.