Right, i've only read the title and not much else so heres my view.
Stator, measure it if it falls between 115-124 or near amps, its fine.
Your problem lies elsewhere.....
The coil, you cant really measure but check the joins are SOLID. E.g the connectors are properly crimped and dont slide off easy (as my old trike used to do this when i hit water hard. and it would cut out)
Next, check your cdi wires. The wires attached to that white plug. If one is loose or pushed back in and wobbles theres a good chance its not making a connection, what happened was on my old bike the bullet thing had ripped off, and someone just shoved the bare wire back in. It worked, but only now and again....
Next thing. Spark plug, it MAY be this. Chances are slim but if everything else has been checked then this is the only thing it can be
Check your rotor pickup, my 140 once ran a 17t front sprocket. This larger sprocket caught a rock and lodged it between the cases effectively cracking the case (just an outside split of about 2.5inches) But inside it wrecked havoc. The stone had forced the case upwards, bent BOTH case bolts, the rock managed to penetrate partially into the case and stuck on the second sidewall reinforced bit. This is when it bent the bolts, then because the bolts bent it forced the case to hit the rotor pickup (bottom right under flywheel) and bent it, then it DID run but only for 20 mins then it finally snapped.
small possibility of the htlead/cap being faulty.
Next check your kill switch, take it off maybe. I think thats everything mate just go through it all