Did you reset your floats?
You said you had knowledge of cars...
Remember vapor lock in the old days (say 70's or so)?
I know on a Solex carb, the heat from the engine could cause a low float to evaporate the fuel before it's able to fire (when hot starting) and a high float would boil over.
Smell the exhaust when it won't hot start. The degree of raw gas smell will help.