My brother-n-law took a 6k mile ride in June/July and had this exact thing happen. It only happened in weather over 100*f.
Last week, some friends of mine and I took a little three day ride around Washington, and what do ya know....it happened to me too! It only happened when temps were in the triple digits. The first time we had stopped for a swim in the river, and upon restart, the fuel pump just kept pumping when I turned the key on, and we could all smell fuel coming from my bike. I turned the key off and tried it again, and it was like normal, the pump did it's thing for a few seconds and quit. However, the bike was already flooded. So, position throttle to WFO and crank until it fires, spits, sputters, takes off and blows black smoke, and then runs normally. It happened every time we stopped unless I fired the bike right back up within a minute. There has to be something that can be done about this, as it's obviously NOT an isolated problem.