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Discussion Starter #1 (Edited)
Here's the problem, starting my bike after a two day weekend (not ridden) it leaks gas for a couple of seconds from the left side when on the side stand then stops. Doesn't happen again all week so long I ride it every day. It doesn't look like it is comming from the vent hose since there is gas dripping down the case. I can't see where it could be comming from with the tank on. The funny thing is it stops completely and never happens at all all week. It has happened for two weeks in a row now.

What do you guys think?
 

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What are you doing differently over the weekend? Is it getting hotter? Are you riding on rough roads and maybe ther's a small crack in one of you fuel fittings?

I'd try to duplicate the symptom and then quicly start ripping stuff apart in a frantic search to find the cause before I had a fire to put out.
 

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Discussion Starter #4
Male fittings have been replaced with metal ones. Female ones haven't been replaced yet (though I have them). I was going to un-bolt my gas tank and leave it sitting for a couple of days then do a test like you guys said. Thanks for the input.
 

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Discussion Starter #6
giomanach said:
Maybe your O-rings went bad?
I guess that is always a possibility, I would highly doubt it though since they are partially brand new (*with the metal connectors). I even lubed them up before using them.

I'm hoping it's the breather line to charcoal canister just came off since it's the only think I can't see.

Has anyone disabled the charcoal canister? For "racing" use only that is :naughty:
 

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I just removed mine the weekend before last. It takes a little wrangling to remove the bolt holding the bracket, and then it takes some finesse to twist everything out. Other than that it's very straightforward. Just make sure to note where the vacuum lines used to be and remember to route them out below the engine. Also, I wasn't paying attention and capped the vacuum lines between the engine and the cannister...only realizing my mistake when I went to reinstall the tank and saw I'd left no hose to fit the vacuum actuator. I just pulled the old line off the can and fed it between the junction and the actuator on the tank.

Easy stuff.
 

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Discussion Starter #9
petevegas said:
Is it possible you overfilled the fuel tank & the overflow was leaking?
Tank was half empty this morning when it leaked. Funny thing is that after Monday morning there isn't the slightest hint of a fuel leak.

Is it possible I overfilled it and the charcoal canister is full of fuel???
 

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giomanach said:
I just removed mine the weekend before last. It takes a little wrangling to remove the bolt holding the bracket, and then it takes some finesse to twist everything out. Other than that it's very straightforward. Just make sure to note where the vacuum lines used to be and remember to route them out below the engine. Also, I wasn't paying attention and capped the vacuum lines between the engine and the cannister...only realizing my mistake when I went to reinstall the tank and saw I'd left no hose to fit the vacuum actuator. I just pulled the old line off the can and fed it between the junction and the actuator on the tank.

Easy stuff.
I don't understand why you would want to remove the charcoal canister :stir:

The function of the canister is allow the tank to vent without sending fuel vapors into the atmosphere. It does this by routing the vent opening through activated carbon. On start-up, manifold vacuum pulls air through the carbon and clears the trapped vapors. Doesn't do anything bad, no affect on runability or power, why disable it? :silly:
 

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Discussion Starter #11
Koop said:
I don't understand why you would want to remove the charcoal canister :stir:

The function of the canister is allow the tank to vent without sending fuel vapors into the atmosphere. It does this by routing the vent opening through activated carbon. On start-up, manifold vacuum pulls air through the carbon and clears the trapped vapors. Doesn't do anything bad, no affect on runability or power, why disable it? :silly:
Racers usually remove all emission type of stuff like this for the purpose of weight savings.
 

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dumbcomputers said:
Racers usually remove all emission type of stuff like this for the purpose of weight savings.

OK...are we talking about racebikes? I thought this was a Brutale. BTW - if the system is functioning properly (i.e. canister not filled with liquid) you might take off a pound or so. :jerkoff:

I'm real curious about your fuel leak though. I can't make sense of it and would like to know what you find.
 

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Discussion Starter #15
I took the gas tank off last night and nothing looks out of place. I removed the charcoal canister to inspect it and it's not full of fuel or anything. Like Koop said , removing it doesn't really lower weight much at all. It is very very light. The only benefit I see is it does free up some space under the tank and makes working on things in that area a little easier.

I'm going to wait a couple of days and try to simulate the Monday morning start up to see if I can figure out where the gas is comming from. My only current theory is that it's the connector to the fuel rail on the left side. It's a little looser than the right one but don't know if that is normal or not. Again it doesn't leak at all when I prime the fuel line or start the bike.
 

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dumbcomputers said:
I took the gas tank off last night and nothing looks out of place. I removed the charcoal canister to inspect it and it's not full of fuel or anything.
I'm curious to know where this charcoal canister is located? I took the tank off my F4 for thr first time, and I don't see a charcoal canister anywhere. Thanks.
 

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Discussion Starter #17
On the Brutale it's sits right below the throttle bodies between the cylinders and the gas tank when it's mounted.

BTW: after removing it, it did make the idle a little bit smoother. Not that it was not smooth to begin with but it did make a little smoother.

Update: It has not leaked it a while now, I'm keeping my fingers crossed. I'm hoping that it was the quick disconnect at the fuel rail which wasn't fully locked in. I'm on travel for a week so I have a really good test next Monday morning.

falcopilot said:
I'm curious to know where this charcoal canister is located? I took the tank off my F4 for thr first time, and I don't see a charcoal canister anywhere. Thanks.
 

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Discussion Starter #18
:cussing: dammit...It's still doing it. I left my bike sitting for seven days when I was out of town an this morning it took a piss of gas. If I had to guess it was about 1 or 2 oz. then it completely stops.


Any ideas??? I'm really baffled.
 

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dumbcomputers said:
:cussing: dammit...It's still doing it. I left my bike sitting for seven days when I was out of town an this morning it took a piss of gas. If I had to guess it was about 1 or 2 oz. then it completely stops.


Any ideas??? I'm really baffled.
It seems to me there's a high likelyhood that gas is getting spit out when the fuel pump primes. Now, are you POSITIVE this is not happening while you're riding? It may be that it is, but you're not noticing b/c it is a much smaller volume (as the pump is already primed).

Maybe you've got a split in a fuel line? How's your fuel economy?
 
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