Not a dumb question. I just ran my 120AX and after a couple of minutes the engine was too hot to touch. I think somewhere around 250 degrees is fine, and that's hotter than boiling water.

I found with the AX engines that if I stop priming the engine just before fuel gets to the carb, it's just enough and starts on a single flip.

They are great engines; I'm really glad you're getting yours dialed in. It will continue to develop more power as you run another gallon of fuel through it, so enjoy!