Fluid Dripping From Under The Bike

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FJRocha

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Last week, as I come out of work to ride back home, I found a small puddle of what seems to be dark gasoline (or oil + gasoline) under the bike <_< . The fluid is dark and has a faint smell of gasoline, it is immediately under the point where the side stand meets the bike. The first day I thought it was a prank from my coworkers (you know, the old "spill a little oil under the new bike to spook the owner" routine), but the second day, I found a smaller, but similar puddle. I have inspected the under side of the bike, and could not find any oil or fluid on the surfaces. One of the drain hoses was a bit dirtier than the others, like if it had dried out, but had gasoline at one time. :huh:

Is it possible that the gas tank was overfilled and the spill is just some extra gas comming out of the drain hose? Or could it be that the bike was marking its parking spot? It does not do it at home :ph34r: I've noticed how the other bikes at work (mostly HDs) gravitate to park at the other side of the motorcycle designated parking lot. ;)

 
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Not to worry, it's the overflow tube from the tank doing what is supposed to do. Prolly just releasing some vapor build-up. The gas is dark and dirty because of the dust in the overflow tube.

 
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Was the bike sitting on asphalt, concrete or living room carpet. If the fuel is on asphalt, it'd get gummy pretty quick and look like an oil leak. On otherwise pristine concrete, if it were quite oily, I might be a little concerned. If it was on carpet, then you obviously are quite insane and don't need to worry about the bike venting fuel at all. :lol: :blink: :lol: :blink:

 
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Mine was doing the same thing when i first got it,no matter how much gas was in it. Seemed to quit around 450-500 miles. Dealer said it was normal during break-in,which is bullshit. I ordered extra small breather like the one in the other hose next to it. Haven't seen a drop since. :)

Yamaha breather part#4X7-2149Y-00

 
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It keeps on peeing on the parking lot... particularly during the hottest time of the day. Seems like the heat expands the gas in the tank and pushes it out throught the hose...

I'm just concern of someone throwing away a cigarrete butt and it landing right in the puddle. :blink:

 
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I have a co-worker with a new chopper. A real loudmouth, matches his bloated noisy bike. Every once in a while when he's not looking, I'll pour a little drain oil from the shop under his bike. Drives him nuts! :haha:

Are you sure somebody's not doing the same thing to you?

 
Are you sure somebody's not doing the same thing to you?
Yep, I have seen at least one drop falling from the hose. The puddle is a bit strange, it is wet on the outter perimeter, but dry in the middle, I'm already out for the weekend, but next week I'll take a picture to demonstrate what I mean.

It only happens in the heat of the day, I have not seen it in the garage.

 
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If your gas tank didn't vent, it would buckle (if not explode) with the expansion of gases in the tank as the thing heats up. Atmospheric pressure also influences the situation.

Airplanes essentially all vent fuel. That's why it's not good to smoke anywhere near them. As an aircraft flies, the air pressure changes with altitude, and that puts more or less pressure on the tanks. They have to equalize pressure, otherwise they buckle or break. Not good. If the tanks are full, the gas pushes out the vents when the gas expands. Better that than a new wing!

Also, a FI system is under pressure and prehaps as the temp changes, the fuel system is releaving the pressure from extra unused fuel once the engine is shut off. Just a guess..

Depending on how hot it is and how much the line is venting, you may have a problem. Mine drips a little when it's really hot. It doesn't seem an exhorbitant amount, and in my garage over night, I don't see a wet floor. I ain't gonna worry about it.

So if you don't get the leakage at home, just at work, it could be a fuel venting situation, or it could be revenge. More than likely, it's normal, especially if it only happens out on a hot ride, not when parked overnight, and not dripping continuously.

 
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Mine does the same thing. I too have seen a small drop from the vent tube, and mine also does not do it at home. It does seem to be related to the hot outside temps, but it does not matter if the fuel tank is full or not. I'm glad I'm not the only one.

Rick M ;)

 
Mine has done the parkin lot pee many times.

I have asked this question atleast a couple of different times.

My FJR does it when it is sitting in the hot sun when it has a 1/3 or more gas in the tank.

I did put a heat lining shield under the tank but still dont know if that did the trick.

One Forum member said his red vent piece under the gas tank lid was about to come off.........but mine was fine and that was not the case.

 
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