99.9% of the problems people have with starting ZDZ's is not getting fuel into them when cold. The choke must close completely or you're wasting your time and arm muscles...
That being said, if they're still hot they can be difficult to get going again. If it's still just a bit warm say after sitting for 20 to 30 minutes mine will usually start without choking on the first or second flip. Once it's been run that day and it's cold, like sitting for an hour or so, usually one flip choke on, choke off ignition on and they'll go the next flip.
They will start using what I call the "DA method" of flipping them choke on, ignition on until it pops then turning off the choke. That tells you there is fuel there, but they also wind up flooded when you do that so proceed accordingly if you do it that way and it will take more flipping.
But like I said, if it's still hot then it's strictly a guessing game and I've not found a perfect solution. Basically it's a lot of flipping but some guys will intentionally flood them so they've got a known situation, others just play with how far open the throttle is, some just let it cool off a bit. That's my preferred solution...
