Stop with the infrared thermometer. That will not tell you the proper temps. In any case it does not sound like you are overheating and seizing.
The Hobbits, Express and express II come ridiculously over jetted to begin with. The #1 problem I have had with every single one I have owned (4 now) is a clogged exhaust because of the stupidly rich jets. Put the stock jet back.
It's quite possible you still have an electrical issue. When you say you swapped out the condenser and stator, did you swap for new parts, or used? A bad coil on the plate or condenser would act exactly like this.