Hi,
If your fuel tap has a "prime" position, turn the selector to that and try starting the bike; if the bike runs you need to look at the vaccum line to the fuel shut of valve.
Another way is to get a syringe, disconnect the fuel line from the tank and attach the syringe full of fuel as a temporary fuel suppy. Once again, if the engine runs you need to look at the vaccum line.
If the vaccum line is intact then you may have a defective vaccum supply valve.
Take care with fuel during this process and have an extinguisher to hand.
Cheers
westcountry, October 2013
