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1981 Honda CX500c
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Hello all, a couple months ago I started having a very fast fuel leak out of the left side of my carbs, high up, possibly above the float bowl even.
Tightening the float bowl screws seemed to stop the leak for a while until last month when the leak returned worse than ever. I enlisted the help of another local forum member, Randall, who is my go-to for these types of things. We did a full carb cleaning using Larry's book, polished all the brass, checked floats and overflow tubes for signs of wear, and replaced visibly worn rubber and reassembled. The fuel leak persisted.
I rode the bike home right after and replaced the float bowl gaskets again which stopped the leak, using the knowledge I gained from the rebuild.
Two weeks of good riding without incident followed, including a ~200 mile trip into Wisconsin and back.
I went to start the bike and rode to the gas station on Sunday last weekend and once again, fuel started dripping out at a rapid pace, from the same mystery spot. Profusely!
I am at an absolute loss and hoping for some advice. Summer is whizzing by and my bike is sitting in the garage. I also tend to rely on my cx for commuting fairly frequently. Please let me know if you've got any advice that I haven't tried, short of shelling out $650 for Murray's which (sadly) isn't in the budget.
Thanks in advance!
 

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I am not a carb expert and I am sure you'll get good advice here, but to start with if replacing the bowl gasket fixed it I would think your float level is set too high or you have returning debris entering to hold the needle valve open. The float level should be set just below where the gasket seals so a bad gasket shouldn't be a leak like what you are describing.
 

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'84 CX650E that is evolving into a GL500
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The first thing you need to do is establish exactly where the leak is. One way to do that would be to remove the tank, cover the carbs with some kind of fine powder (flour, talcum, anything fine) and with the tank out of the way and either the tank connected to the carbs by a long hose or an alternate fuel source connected turn the fuel on and watch for tracks in the powder.

I can only think of a couple of places above the float bowl where fuel can leak out.
One is the atmospheric vents (those little pipes sticking out from the inboard sides of the carbs that look like they should have something connected to them but they shouldn't). If that's where the fuel is coming from see what Doug said above.
The other is from the pipe/tube that runs between the carbs and has the fuel line connected to it, specifically the o-rings that seal it to the carbs. But if you did a full job on the carbs those o-rings would be new....
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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We didn't divide the carbs. I usually leave them together unless there's an indication of failure of those o-rings. I think Kurt's initial request was for cleaning, so I want looking for leaks.
We should take another look and do the clear-tube-on-the-drains test to verify the float levels.
 

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I know this sounds silly but try tapping on the carb with something like a 15 MM wrench. My Savage had basically the same problem and it was a stuck float. Tapping it unstuck it. You can drop the float bowl and check to see if the float is moving freely. I haven't had my CX500 bowls off but on other Honda engines I have worked on the float moves up and down on a pin and if it is off center it will cause your float to stick.
 
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