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Fuel spilling out of bottom of carbs

Yup fuel evaporated and left varnish and what ever else behind on the float needle. If it is ethanol fuel it probably made the rubber tip on the needle hard as well as probably turned parts of the aluminum on the inside of the carbs to dust. Need to disassemble the carbs and see how bad they are and give them a good cleaning along with whatever else is bad...float, needle and seat, bowl gaskets.
 
If ethanol in your local fuel then that evaps the gas out of the bowls at 5X the normal rate. I have trouble with the same on my 550F after as little as 3 weeks sitting, these non pollution controlled bikes have fits with it what with the vents being so exposed to air. Longer sitting you need to tear down to resolve any varnish/gum issues, if shorter term I began to simply yank fuel line off petcock and blow into the line with an air tank at 100 psi, of course you don't apply the air solid at that pressure, just bring the air nozzle close enough to the end of fuel line to pressurize it up a little bit, it pretty much can pop the needles loose with zero harm if they stick shut to give no fuel. The ethanol can make either one happen, flood or stick shut. The leftover sugar remaining in it does the sticking along with interaction with rubber to soften it like glue. My needles are steel to a brass seat and still stick. Taking carbs apart will have you finding the needle is stuck but the slightest touch with a finger unsticks it if no deposits inside (again, sitting say only a couple weeks). How I came up with the quicker fix than yanking carbs. Mine tending to stick shut and no fuel in carbs, often all 4 do it. Same cause though. Ethanol is transparent as long as you run it solid and every day but let it sit in something to where it can sour the gas and oh, the problems!
 
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I just take out the drain screws and shoot compressed air into the drain hole after all the gas is out. Works every time.

 
That might work well. One of the biggest issues I find is that the highest fuel point dries up first, and that often being the idle fuel feed restriction, or the pilot jet. The smallest hole (around .013" or so there) tends to dry across the hole because of capillary action and then the varnish forms over that to plug the idle feed. Why so many have utter fits with bikes not idling right and /or pulling away from idle. Blasting air up in there after a drain would tend to blow the pilots clean and open.

The first DOHCs have pure hell there as the idle and primary off-idle are interconnected and the idle going lean then makes the off-idle super rich because of the way the fuel circuits are set up. It drives guys nuts. The plugs come out dripping fuel and they then try to lean the idle out more when it is so lean already it will not work.
 
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