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Sorry....but.....I'm not there to see it or smell it....so my best advice is that if you think it is abnormal and don't know what it is, take it to a reputable shop immediately. Somebody that knows these bikes needs to actually look at it to see what's going on.
 

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True it can be serious or it can be fumes. Mine had issues like this.

When the AIS is removed the vapors can be whiffed. Not sure where they come from. My bike is a 2000 49 state. No tank vent.
Cal models have a tank vent which is routed to the intake for reburn.
Pollution control in other words.

Could be leaking fuel filter, fuel lines, Carb bowls, Gas tank leak, Petcock, Damaged gas tank cap. Ect.
Loose or broken Vacuum hoses, on carb or AIS.

bad Running conditions can usually be caused by the latter.

The potential for a fire is evident, Check it close with a flash light,
Or have it inspected by reputable source.

jake
 

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I get the same thing every once in awhile on my 650 too but thats usually when i'm getting low on gas and the fumes become much more and noticeable. Might be your case if it goes away when you put gas. Have a Happy New Year!
 

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Discussion Starter #5
Thanks Guys I was thinking that it was happening when the tank was getting low .Next time I get it I will have the flash and a sniff tube ready to go see it I can isolate the area.
Bike is in storage now so guess that will happen next spring.

Laybacklenny
 

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Strong fuel smell most likely will be from a leak some where.

Faint fuel odors will be much less strong (no visible wet areas)

Paper towels used to wipe hoses and carbs, petcock, ect (where you can reach) can detect where a wet spot might be.

Sometimes they can be hiding very well.

Good luck come spring.
 

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Thanks Guys I was thinking that it was happening when the tank was getting low .Next time I get it I will have the flash and a sniff tube ready to go see it I can isolate the area.
Bike is in storage now so guess that will happen next spring.

Laybacklenny
I've noticed this with my 1100 as well. I only get the fumes when its low on fuel. Fill er up, and I dont smell it anymore. Of course, wind conditions are a factor as well. Had the same deal on my 99 Victory and by golly I spent hours trying to isolate it....but was never successful. On the 1100...I "think" it has something to do with that tank cap because in my case thats where the odor is strongest.

ps...really wish I could lose that gas cap. I fight with that abortion every time I fill it up with gas. Doesn't want to seat. :(
 

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The tank cap by design must let air in to let fuel flow out of the tank.
CA models have a tank vent that draws those vapors and fumes off
and into the tract of the intake for burning.

On ventless models (49 state) The fumes have no where else to go but back out the openings in the cap that allow for this air to be drawn in
Otherwise turning the petcock on would allow for some fuel to flow but then as vacuum builds again the bike would starve for fuel and shut off.
It is designed this way so the engine keeps running...

jake
 

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The tank cap by design must let air in to let fuel flow out of the tank.
CA models have a tank vent that draws those vapors and fumes off
and into the tract of the intake for burning.

On ventless models (49 state) The fumes have no where else to go but back out the openings in the cap that allow for this air to be drawn in
Otherwise turning the petcock on would allow for some fuel to flow but then as vacuum builds again the bike would starve for fuel and shut off.
It is designed this way so the engine keeps running...

jake
Makes perfect sense. I dont smell it on my Harley. Is that because its fuel injected maybe ? And the pressure is handled differently ? Never really given the subject much thought. Thanks.

EDIT : Come to think of it the HD has a fuel tank vent which vents out the bottom of the motorcycle. I need another coffee !!
 

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Really Fuel injection or Carb does not matter. It's all in the fuel delivery
to either. Gravity feed means it must have a vent to allow for fuel to flow.

My 650 has a fuel pump but still has carbs. It supply's the carbs a constant fuel pressure.

On fuel injected bikes the fuel pressure is much higher due the the use of Injectors which spray the fuel (atomized) and is controlled by the PCM. Or computer.
 
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