First things first. Does it do this all the time or only when the motor is cold? Choke should be used when starting and warming a cold motor. 1-2 minute idling with full choke at start-up should be enough to at least be able to ride.
Does adding some choke, help? Can you rev the motor at cold start-up? what is idle rpm?
Next how scared of twisting the throttle are you? If you are timid with the throttle, on that bike it will protest. If you are going to slow when shifting to the next gear, it will protest.
Now, tell me about the bike? Was it being riden buy the PO or did it come out of storage? What was the condition of the oil? Did you do any other servicing, plugs, filters, fuel, coolant, brake or clutch?