Got it from a dealer, started right up, test ride, etc.

Brought it home in the back of a pickup, heavy rain.

Got home, rode it around the driveway for a couple minutes then put it away.

Son came over a couple hours later to check it out. He turned the fuel to reserve, started the bike, and about two minutes later it coughed, and died. I kinda joked with him, asking if he didn't know difference between reserve, and "on"....he rides a Buell Lightning...

I went out today to start it, no go. It will turn over, and sometimes run for a few seconds, and then die like its running out of fuel.

I took off the air cleaner, just because...thought the magic "look at the carb" might fix it...it smelled like gas, so I thought maybe I somehow flooded it. The dealer was very specific..do not turn the throttle while starting it, so I didn't, at least the first few times. Later, I was trying all kinds of throttle positions, hoping it would catch and start. So, I probably did eventually flood it.

I took out the spark plug to test for spark. It was a little wet. Cleaned it up, checked the gap, checked for spark, got good spark, put the plug back in. Tried again, no go.

I also don't know how old the battery is. The date codes on the battery have not had the holes punched out, so now way to date its age. I put a an SAE pigtail on the battery, and discovered the bolts really weren't tightened down. After I tightened them back up, the bike seemed to fire right up, starter turned over strong, fired up, seemed to be operating normal...and then quit. I put a battery charger on it, voltage about 12.8.

With the aircleaner still off, I tried to start it a few more times.. Once or twice it kinda farted, and I saw a vapor of gas blown out the carb, similar to a backfire.

That's where I am.

Any advice?

I'm clutching at straws...is there any chance that water might have been in the bottom of the gas tank, and when he put it on reserve it sucked some water into the carb?