yes, i would start going through your electrical. check all ground, even where the coil mounts. remove the caps and see what the wires look like. replace the caps, as mentioned. check the harness for melting/chafing. ohm out the coil on both sides. then, remove your flywheel, correctly, and check for corrosion and all wiring connection and ground points on the stator, including where the timing plate mounts to the engine, and stator. while the fluwheel is off, give it a good firm shake and see if you can hear anything and slide a scewdriver in the inside and see how it jumps from magnet to magnet........also, have you checked the compression and reeds? exhaust obstruction such as a broken silencer core or fuel in the chamber?