what causes a 196cc to run fine untill full throttle

[Rat]

NGK is probably the route ill go on plugs, it gets to 40c to 45c here in the summer with -10c to -20c in winter if that matters

would colder weather affect the idle air screw setting due to air density change or something? or am i thinking too hard about it

It can but generally if it's adjusted and jetted properly it's only a matter of running the choke a bit longer

i noticed u dident comment on the popping at idle, would u say its concerning or should i not worry about it

Short straight pipe header, I wouldnt worry about it at all. I'd worry about getting everything under control and tune it properly by monitoring its behavior under load

ill try messing with tach connection to plugwire aswell as idle air screw to improve idle im sure i have it set a bit off after reading how u described to set it up

A too lean AF setting will idle higher than it should and a too rich setting will stutter and miss as well as emit black soot puffs from the exhaust