Fuel seep through hose/fittings?

S

Sunspark

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Hi:

I have a bike that has less than 2000 km on it but I think it has more smell than it should. What is happening is that often after riding it and especially (but not always) if I shut it off with the kill switch the garage will smell even days later of "bike". I want to say it is gas but I am not sure that it is. It is some sort of petro type odour that is noticeable when you open the garage door and walk in. It seems to happen less if I turn it off with the key but this trial and error method isn't predictable. Some days it is stronger than others. It is not a consistent strength.

There are no drips visible on the floor at any time.

I find myself wondering if this might be seep of some sort through the black rubber hose or clamps?

Has anyone heard of fuel line hose/clamp issues on newer vehicles?
 
Yeah, but it's been cold not hot and it's been garaged away from the sun. My garage is lame and is not airtight at all. All around the roof is gap instead of seal. Rode bike on Saturday night, opened garage Sunday night and it was gaseous in proximity to the bike. I suppose it is possible the gas cap itself is malfunctioning. That's where the vent is, there is no vent hose.
 
Not sure. I am the second owner. It's a 2012 so I think a year, possibly less. I do know it sat 4 months before I got it.
 
Then there's nothing leaking through the hoses. It's just evaporation as Jamie said. Bikes don't have evaporative emissions controls like cars do.
 
If this is true and it's not an o-ring or a clamp slightly not tight enough then that is a bummer. I'm actually a bit allergic to air pollutants. Ah well, it's only a 250cc. I really like it though. But if I was to ever get another I would seek out a California legal bike or an electric.

I don't want to give up. In the short term, I suppose I could consider ultraviolet dye. I don't have it or a blacklight but it seems like a pretty easy test. Dump it in and then look for glow that didn't drip onto the floor.
 
Make/model/year, please ...

Fuel injection systems are normally very well sealed, and the fuel tank will only vent in response to a large temperature variation. Fuel contained in the fuel rail can't get out through the closed injectors, and the quick-connect fittings are all well sealed with O-rings. Also, when you turn off one of these engines, it does so by cutting fuel supply (no more spark, but also no more injector signals), which pretty much removes most of whatever tiny amount might be sitting in the intake runners by the engine spinning a few revolutions more after you switch it off. Result - practically nothing left to evaporate.

Carbureted fuel systems are another matter entirely. Carb float bowls are inherently vented to atmosphere. There is surface exposure of the fuel to the atmosphere inside every fuel jet in the carb, too. The whole intake manifold downstream of the carb will have its inside surface wetted with fuel and that's true even after shutdown because the carb has no way of knowing if there is spark - no way of shutting off fuel delivery to let the engine draw the last bit through.

The evaporative emission situation is one of many reasons that carburetors are becoming obsolete.
 
Brian P said:
Make/model/year, please ...
Click to expand...

Hi, 2012 Suzuki TU250X. It's an EFI bike.

Part of the reason I wonder about all this is because when I was reading on the net I came across some Harley threads who had a similar problem and sometimes the answer was to not use the kill switch which I often do use.

But today I was reading this Suzuki SV650 thread and they were talking about a common hose issue on their bike, specifically the little hose that goes between the two throttle bodies is held on by spring clamps at both ends and can get looser and begin to leak fuel.

Of course having a thumper I only have 1 throttle body but it did make me wonder about spring clamps versus real hose clamps as the SV and mine are both the same manufacturer.

Then I was reading a car forum and they were talking about how the hose including braided hoses itself can reek down its entire length, and that the only real fix the car people had other than a hard fuel line was a Teflon coated interior tube so the ethanol and other stuff wouldn't attack etc. the rubber.
 
Nothing has happened yet but I have since learned the fuel line hose on my bike is made out of EPDM.

Seems to me that a fuel hose could be better quality.
 
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