You can download the manual, and do throttle body leak test. That would be the easiest
2007 XB12STT - 8000miles (purchased new in the crate June 2009)
AMSOIL 20W-50 Motorcycle Oil
Recently I began to hear a funny noise from the top end of the XB. It sounds a lot like a loud sucking noise, maybe even some kind of vacuum leak. The bike will idle just fine for a while, then a stumble occurs, then shortly thereafter it will die. If I blip the throttle a bit the bike runs fine. Any idea where the noise could be originating from?
BTW, the oil level is good, primary is adjusted properly, and all electrical connections visually look good. Only strange thing is this sucking noise that suddenly began.
I have not checked the headers and cylinder heads for tightness, although with just a visual check I do not notice anything loose or in bad condition. No oil leaks, drips, runs or anything strange.
You can download the manual, and do throttle body leak test. That would be the easiest
California bike?
yeah its a california bike
evap hose?
just checked the throttle body. the evap hose is connected and there are no problems with it running towards the canister. i removed the air scoops from each side and it sounds like the leak is from the throttle body/head seals. goin to try to tighten it a bit and see if there is any improvement. it's a tight fit because of the frame spars, but an allen key could fit in there.
ttt
Might spray starter fluid around your intake manifold while the bike is running - if your RPM's bump up it means you've got a leak.