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Discussion Starter #1 (Edited)
2009 V Star 1300 Tourer... I have posted on the V star facebook groups but just trying to cover my bases and figure out as much as I can since I am away from the bike for a month or so.

Basically after I bought the bike, first fill up I filled full. Up to the neck. Fuel leaked out of the cap and down the tank. I chalked it up to overfilling it and it was my fault. Great, don't do that next time.

Second time I filled the bike, I put the nozzle in the tank on the baffle in the tank and filled it until the pump clicked. Figured it was not overfilled this time. Rode for 15 minutes or so, parked the bike, came out hour later and fuel had ran down the tank, pooled up around the gas tank hinge, and a tiny puddle on the ground. Wiped it off and took off for a ride to use some gas so it would quit leaking. Well for the next 20 minutes I had to ride with a rag to wipe the fuel off that would be coming from the puddle around the gas cap hinge.

You can see here where the gas is releasing the glue on the cap cover but that bottom corner is where the fuel is leaking from.
http://i47.photobucket.com/albums/f155/Vink70_99/tank_zps0fa0c631.jpg

And here, I blew compressed air through the orange opening as well as the opening in the lid.
http://i47.photobucket.com/albums/f155/Vink70_99/tank2_zpsb0c17ef1.jpg

Air came out the breather tube that runs down the frame, as well as when i blew air through the lid, it came out the latch mechanism top dead center of the picture.

Part of me wonders even though to close and latch the lid, I have to push down on the lid, but that it is still not sealing because when i open the lid, there is gas sitting on the lip of the top of the tank where that orange piece is...

Any help or thoughts would be appreciated!
 

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My first thought would have been overfilled as well, just like you.. However, since it obviously wasn't the second time around and it seems to continue leaking, not just leak when it is "sloshed" -- It's almost like it's building pressure or a vacuum inside the tank... but if the breathing tube is open then I'm at a loss... I am very curious to find out what it is, so I'm following this post.
 

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Did you ever find out what was going on and fix it? I learned the hard way not to leave the gas pump "autofilling" the bike like you can do on a car ;-)
 

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Discussion Starter #4
Never figured out what it was. I don't use the auto fill. I don't feel like I over fill either. I think something is wrong with the vent valve or hose. Probably replacing the gas lid at some point.
 

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That's a head scratcher. If you fill to the bottom of the cup in the tank opening with the bike resting on the kick stand, it should be not be a problem. The empty cavity above the fuel when filled this way should allow for expansion of the gas when it changes volume (Thermal Expansion) as it warms up. It should also compensate for changing the bike to the vertical position. When the bike is upright, the gas in the cup will become higher and maybe even come up near the top. Gasoline has a fairly high expansion with temperature increases.

Many times airport personnel, trying to sell as much fuel as possible, would fuel up an airplane to the top with cold fuel and as the airplane sat in the hot sun, fuel would expand and run out the vent tubes. I've seen gallons run out the vent tubes. Good luck with your search.
 

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Discussion Starter #6
I know what you are saying about thermal expansion. But I think its due to the fuel sloshing in the tank and getting up past the seal as well as the pressure building causing it to leak. I have filled it to the top and filled it to the top of the baffle in the tank with no success. I am not sure what the fix is but at he same time I just have to fill it and ride it for a bit immediately after.
 

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The vent in the fuel cap should vent off air as the fuel expands, provided it was only filled to the bottom of the filler cup. It should also allow air into the tank as the fuel is used preventing a partial vacuum and fuel flow stoppage. There should never be positive or negative pressure in the tank if the vent is working properly. Still scratching my head. :confused:
 
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