Ok guys, I could use some input cause this issue is driving me insane. It all started while at freeways speeds the bike had no power, even with the throttle pinned wide open it was stuck around 80mph. Around town it pulled strong and behaved normally. So figuring it was a fuel issue I cleaned the carbs, replaced the fuel filter, cleaned the k&n and put everything back together. Now the bike fires right up, runs fine for about 10 - 30 seconds and dies like its out of fuel. At that point it wont start until sitting for awhile, then fires right back up and dies again in the same manner. When I pulled the plugs after it was running they are damp with fuel not oil. I originally suspected the fuel pump, but, it feels like it is pumping. Though I'm beginning to think that is not the issue. Any ideas?

1999 CBR600F4

 

It can be an intermittent fuel pump issue. Maybe you can hook up a line to it and turn it on and drain into a gas container to see if the flow is constant.

 

No idea does this happen on bikes equipped with a fuel pump, and im not familiar with f4 mechanics, BUT the symptoms do hint that when you put the bike back together you might have kinked a possible tank breather hose creating vacuum into the tank that has to sit out to stabilise. Fire it up, let it die and then immediately open the tank cap to see if it opens normally or goes "pop" or does other sucking sounds.

Just shooting in the dark but that came into my mind...

 

I was having issues that I assumed were fuel related however after checking out my pump it appeared to be pumping rapidly too quickly as a matter of fact. Sometimes it failed to pump to its full capacity I made the bike difficult start. I remove the fuel pump in rode the bike around for several weeks and everything ran fine it had an issue where after around 80 miles on a tank hey couldn't produce enough pressure to feed the carbs I was start to starve a bit for fuel. After being tired of dealing with that I also noticed that the rectifier was having issues because I noticed my headlight getting brighter as I revved the motor. I checked the voltage at the battery and it was over 18 volts. Are placed a rectifier and recheck the fuel pump. Now I'm sitting at just under 14 volts and guess what the fuel pump works perfectly have added a couple thousand miles to it without a single problem. I'm guessing the extra voltage didn't sit well with the fuel pump maybe you could check your electrics.

 

I've looked at all the hoses and even tried starting it with the cap off, same effect. Guess my next step is to review the electrical, and or replace the fuel pump.