Here is my issue. I bought a 00 savage 650 with like 1000 miles, had been sitting. It ran fine on rusty fuel. I then installed an inline fuel filter and inline shutoff because the petcock failed. Rode it 2 hours north to school, no issues thank god.
Then the next time I started it up it would idle fine the flood when I accelerated. I got fuel in airbox, into crank, and spit back up warm oil/gas. I changed it out and drained airbox. cut and plugged both ends of the vacuum petcock lines to make the tank-to-carb delivery be gravity fed like a dirtbike carb and rely on the float valve while riding and inline shut off for peace of mind while parked.

--Here's where I'm at now. When parked and idling with the airbox open it idles fine, but when I open the throttle it pissed fuel into the airbox, the more I open it up; the more fuel dumps into the carb/airbox. It actually ignited and threw a flame out  ... glad to have an oily rag nearby to smother the air-box within seconds. . I called a suzuki dealer, they told me all the usual things, but couldn't for the life of them couldn't figure out how so much gas could dump into the carb like that. Any ideas or sugestions would be greatly appreciated I need to fix this thing.

Have you checked the oil level in the crankcase?  It could be the carb has overflowed and filled the crankcase with gasoline - and when the rpm's come up the oily fuel is blown out the engine and through the breather and into the air box.

Teabowl makes a good point or 2 there. I wouldnt start it again till Id had that carb apart & found the problem, & an oil change mite not be necessary, but it sure is cheaper than an engine.

aludy2091 wrote on 06/07/12 at 23:24:17:

Did you disconnect the vac line too?
Otherwise, if the petcock diaphragm has failed, it could be leaking fuel into the case that way.