OK, I haven't had any problems with my bike in a long time, but I have one now. I went on vacation at the beginning of June for 8 days. Previous to that I had ridden the bike almost every day, and everything was fine. Bike sat in the garage with almost empty tank while I was away. When I got back, I wanted to go for a ride so I started up the bike. It was under choke at 2k RPM (that's the speed where I let it warm up) and ran out of gas. I put a gallon of week-old gas in, but couldn't get the bike started after that.
I pulled the plugs, and they were fouled. Put in a new set, and fouled those right away. Carbs were pulled, and looked really dirty. After the carbs were cleaned, and another new set of plugs were put in, the bike started right up.
Now, the bike runs fine around town in 1st thru 4th gears. While riding on the interstate at 75MPH (about 7k RPM) the bike will only go about 5 miles before "running out" of fuel. The tank is full, but I guess not enough fuel is being supplied? I can pull over to the shoulder, downshift, and the bike seems to get gas again. Then I pull back onto the highway, get back into top gear, and the bike will do the same thing. Any ideas? The dealership is booked up for 2 weeks, and I hate to lose all that riding time!

 

something like that happened to me when i had an inline fuel filter in. I took the filter off and havent had any problems

 

I don't have an in-line fuel filter, but I have thought about a fuel filter problem. If the carbs were so dirty, the inside of the tank is probably dirty too. Isn't there a factory fuel filter on the petcock? Maybe I should look into that. Also thought that maybe carbs need to be synched?

 

Sounds like your running lean...i've seen a few f2's with similar problems...including mine...get back on the highway...and close the choke when you hit 6th gear...see if the throttle response gets better....and by chance...does it seem to "run out of fuel" when your especially going into the wind?

 

Yeah, bike does seem to die going into the wind. I think I've found my problem though... I have no snorkels on my upper intake. I think that's causing either 1) too much air to enter the airbox or 2) air forced into the intake holes without the snorkels is too turbulent. I think both of these could cause the lean condition I'm having, so I ordered some new snorkels from the local stealership. $55 for two small pieces of rubber!
I have no idea what happened to the original ones. I know they were on there when I got the bike, but I just now noticed they are missing.