Please Help, Leaking Gas!!!

So I was out at the track today and and after riding for a couple hours my bike started leaking gas really bad. It was coming from the the overflow hose at the bottom of the carb on the left side of the bike, just above the front sprocket. (red box in pic). After I found the source of the leak, I went to stop it by closing the valve from the tank to the carb...but it didn't stop, it slowed down a little but was still leaking none the less (reason the hose from the gas tank to the carb has a vice clamp on it). When I squeezed that overflow tube shut, it just started to leak from the other overflow tubes. At this point I pretty much figured that there is something wrong with the valve from the tank, but I'm still not sure why it is even leaking at all. Everything was going fine then it just started leaking out of nowhere. Also I was messing with the AP timing screw a little bit before I started riding but I didn't really end up changing its position, but could that have had something to do with it? I'm not an expert on these bikes but I consider myself some what mechanically inclined so I'm thinking that maybe the carb is just gunked up and the float is stuck:confused: Any other insight would be greatly appreciated

Thanks yall


the screw you have circled in red is the carburetor float bowl drain screw.... its for draining the fuel from the carb bowl when not in use or during fuel flushing/etc..... this may sound overwhelming if your not familiar with this stuff so i will try to explain the best i can, but there are only a few possible scenarios....Let me explain.... The carburetor Bowl stores a few ounces of fuel readily available for the engine to suck in through the jets in the carb. There is only supposed to be a certain amount of fuel in this area. If there was no way to control how much fuel sits in this area, you would turn your fuel valve on, the fuel dumps through the fuel line, into the carb bowl, and then would continue to flow until the bowl overflowed into the engine, out of the overflow tubes, or any other place it could go, eventually draining your fuel tank completely if the fuel valve was left on.... However, there is a thing called a float inside your carb bowl.... its a hallowed out peice of plastic.... as the fuel passes through the fuel line and into the carb bowl, there is a float which is attached to a needle valve that rises as fuel enters.... picture a glass of water with a ping pong ball in it.... as you fill the glass with water, the pong ball will rise... this is how the float works... Back on subject - the float is attached to a needle valve, when fuel begins to pour into the carburetor, the float rises like the pong ball would... when the float rises completely and the carb bowl is full, the needle valve clogs the area where the fuel would come through... this prevents more fuel from entering the carb bowl... we now have a controlled amount of fuel flowing into the carb bowl and will have no overflowing.... when fuel breaks down over time, it can become gummy,jelly,gunky,broken down and nasty.... if the needle valve had some of this broken down residual varnish on it, it can get stuck either open, or closed.... if it were stuck closed, you would get no fuel to the carb bowl and that means no fuel to the engine - which in that case the bike wouldnt start.... if it gets stuck open, there is no control on how much fuel will enter the carburetor... it will just dump and dump and dump fuel, then coming out of the overflow, into the engine, contaminating the oil, and all over the ground, etc.... THIS MAY BE THE PROBLEM.... however, it could be other things as well..... IF that screw you have circled in red is not tightened all the way, fuel will just dump out of the hose right under it and onto the ground... (you can identify the hose because it sits on a tiny nipple on the bottom of the carb bowl directly under that screw, it runs between the swingarm and frame just like all the other carb vent hoses) DO NOT OVER TIGHTEN THIS SCREW... it only needs to be screwed in until lightly seated, then just a slight 1/8 turn or so, if that... it will break if you try to tighten too much.... it is only there to drain the carb bowl.... THE other possibility would be that the fuel valve itself, (the thing you turn on and off) is damaged and will not close.... if the needle valve was stuck open, and the fuel valve was also stuck open, fuel would just run right out of the bike and your tank would eventually be empty... If the fuel valve was stuck open, and the screw was left loose, any fuel that would enter the carb bowl would drain out of that same pink hose... so it could be a number of things....

What you need to do is first, identify the problem.

second determine if gasoline has contaminated your oil, which if it has can cause some serious problems and you must change the oil 3 or so times to flush the system.

third fix the problem and try not to repeat whatever you may have done to cause the problem.

i just read again and if it wasnt leaking before the ride, but was after - chances are the dain rscrew may have vibrated loose- check it out...

anyone have any other suggestions ?

My needle valve stuck open once, a couple of passes up and down my street fixed it, I think I may have had sand or something, a night I got back from glamis, but it did the same thing. except when I turned my gas off it stopped

if you take the float bowl cover off. i suggest getting hex screws to replace them, unless you dont have a problem with the play-dough screws it comes with.

is it fixed yet? or did you just run out of gas?

yeah I think your needle valve was stuck too.. it doent take much to stop it up. alot of times I will smack the carb with the soft end of a screw driver but in many cases you will have to take your float bowl off and dis-assemble the float valve assembly....

unless you dont have a problem with the play-dough screws it comes with.

LOL!! :confused: I used the exact same wording in one of my posts about those screws.

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