Nope... you definitely have it right. The overflow tube is much farther up the tank and comes directly out the side.
From what I remember, you can bypass the whole petcock negative pressure valve by just setting that switch on the petcock to "prime". You might want to try that and just rule out any possibility of leaks in that hose. If the bike runs fine with that valve in the prime position, but doesn't run with it in the "on" position, then you can be sure your problem is likely a leak in the vacuum system.
Another thing to try is to adjust your idle. You may need to increase it a little to get the bike to run in a stable manner. You can also try your choke to see if richening up the mixture helps.
Cheers,
Owen
|