yes sounds just like the wiki post huh lol. I am having this problem and I have searched a decent amount (always open to links showing me I am wrong lol), but I took my carbs off and clean the jets (40 pilots ) and put everything back together but it still did the same thing. I used carb cleaner with compressed air to clean them. The one way I got it to rev was to apply Positive Presser to the gas tank vent line and she rev'ed great. I am Ordering a new gas cap (I went to clean mine and my friend lost most of the springs   ) and was thinking of getting a new (used) petcock as well.

The bike only started doing this after my friend crash my bike (hit a deer going 60) and once before that when I filled the tank up to the brim.

I am a major noob when it comes to bikes, I just know cars well.

Thanks for any help

try leaving the gas cap open.  also, make sure that there arent any kinks in the fuel lines, and if you have an inline fuel filter, go ahead and replace it.  it sounds like your just not getting enough fuel to the carbs.  make sure the fuel valve on the bottom of the tank is turned all the way on also

Leaving the cap open didn't help, and no kinked lines and no fuel filter. But I am, not sure what to think because its when to see the bike work when positive presser is put on the vent line from the tank. also with the air box all the way out when I add the positive presser onto it, I can see the pilots shoot fuel

so if you left everything else the same, but took the airbox off, can you rev the bike and see fuel? or do you have to put pressure to the fuel line? im thinking your petcock is to blame. it's not letting enough fuel flow. try running on prime?

I took the airbox off to get to the carbs, and I pulled the Fuel tank vent line and put presser to that. When I did that the bike would run and rev.

Quote from: Ju_S12_Turbo on August 02, 2010, 01:48:56 PM
I took the airbox off to get to the carbs, and I pulled the Fuel tank vent line and put presser to that. When I did that the bike would run and rev.

so if you only take off the airbox, but dont pressurize the tank, the bike will rev or no?
have you cleaned the tank out? check the screen in the tank petcock for clogs. im still not 100% sure which vent line youre putting pressure to but if youre forcing pressure into the tank and that's the only way to get a steady flow of fuel, there has to be a clog somewhere.

if you open up the carb drain screws, do you get a steady stream of fuel?  if you leave the air filter out, will it run properly then?

Try running it on 'pri' and see if it revs. You may have a faulty petcock.

I agree with BombJack, or you may have a kink in the main supply line from the tank.  It likes to kink where it bends down to the petcock.  You may take the tank off and see there's no kink, but then put the tank back and the kink reforms.