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Discussion Starter #1 (Edited)
The two carbs have been rebuilt and cleaned, been rejetted slightly, and the needle slightly shimed. Per a previous post recommendation. I checked float needles. These have the plastic type float.

Anyway, I left the gas line on over night and the next morning when I went out to start it i smelt gas. It had leaked out over night and a small puddle beneath it. I noticed the carb itself on right side had gas on it. When I removed the pod filter gas ran out the back of the carb. It had filled up overnight. How, I do not know less the float needle wasn't seated....Any other thoughts or suggestions appreciated.

Thanks Tim
 

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Discussion Starter #3
Yeah, for sure... But I was told that it shouldn't do that at all on or off... there's another problem. I was hoping someone here might know first hand.
 

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No, that is the problem. The floats/needles on these carbs are not perfect on/off switches. Typically they will control the flow of fuel to a flow rate less than what the engine is burning but they will allow some seepage. In this case the excess fuel should have drained through the overflow standpipes then out the drain nipples on the bottom of the carb bowls. You might want to remove the bowls and ensure that the standpipes are open.

CHANGE THE OIL.

When you shut the bike off, close the petcock.
 

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You may have have a split standpipe ( Ive had a few of these) or a float may need a little extra shim or rust/dirt fouling the needle seat. Its the curse of gravity fed carbs. turn your fuel off.
 

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His problem is the opposite. Rather than fuel leaking out through the standpipes it's backing up into the carb body.
 

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Discussion Starter #8
No, that is the problem. The floats/needles on these carbs are not perfect on/off switches. Typically they will control the flow of fuel to a flow rate less than what the engine is burning but they will allow some seepage. In this case the excess fuel should have drained through the overflow standpipes then out the drain nipples on the bottom of the carb bowls. You might want to remove the bowls and ensure that the standpipes are open.

CHANGE THE OIL.

When you shut the bike off, close the petcock.
Remove the bowl and check standpipes. Are these the jetting pipes?
 

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They are brass tubes that stick up from the bottom of the carb bowls. Their sole purpose is to drain excess fuel from the carbs. They have no effect on jetting or fuel flow to the engine.

 

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Sounds like the float needle is sticking. This is why I polish the needle seat bore and the raised ridges of each float needle.
 

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Discussion Starter #11
They are brass tubes that stick up from the bottom of the carb bowls. Their sole purpose is to drain excess fuel from the carbs. They have no effect on jetting or fuel flow to the engine.

Gotcha! Thanks a lot.
 

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Chances are very high that you have a leaking float valve. When working properly, they do completely shut off gas flow. If you put in aftermarket float valves, especially from a “rebuild kit”, roughly half of those valves fail. Get OEM float valves, that should eliminate the problems.
 
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