i checked the sparkplug and cleaned the entire carb

 

hello can i get some help please

 

better video

 

hey bud did you get it fixed did you check the diaphram in the carb it may be bad

 

Bet its valves clearnce. Just went though this same issue cause motor had slipped at wot and downshifted jump timing throw valves off also. I even bought a new carb and coil and plug. Would take the side off check the timing for tdc and see where gear is. Then check valve clearance.