I had the exact same prob with my 05 speedie but my bike died out in the back blocks on no where. Luckilly for me I had read enough of info from here to work out the prob, so basically I just disconnected the tube.

If you can't find it, just follow the tube that connects to the overflow under the tank. You really do need to take the tank off which if you haven't done it yet is probably a good start to your learning about your bike.

Staintune Pipes, K&N Pods, 45 pilots, TBS needles and 145 mains.