Not 100% sure if it is the fact that my bike has a 2 deg advancer on it (unbeknown to me until a week or so ago) but my bike starts first prod WITHOUT choke or throttle, even on a cold day like this morning. If I DO use choke it takes a little while to fire up, 2 or 3 seconds on the button before it fires and if I let go of the start button it will die more often than not unless I give it a neighbour endearing "fistful".
So, I no longer use the choke....