FCR MX on XR 600 - vent line leaking

Recently re-stored a 1999 XR 600r...installed a FCR MX carb...bike runs great, jetting is on...one issue.  After each ride, the vent tube from the bowl, leaks out 4-5 drops of gas...cannot be right.  Any ideas on what would cause this....does not do it any other time but after the bike is stopped and the engine is off.  If the engine is running no leaks from the vent.


Thanks for your help. 

You need to replace the float needle and possible the seat too, if it is corroded; do this AFTER checking to see that your float level is not to high, which would cause it too.

That is not a vent tube, that is an over flow tube.

Four or five drops is somewhat normal. To confirm it is not a float needle seat issue, with a cold bike, open the petcock. Let the bike sit for five minuts or so (engine off). Any drips? Shake the bike (say 10 degrees off of center, not leaning it over). Any drips? If none, do not worry about it further. Seems the fuel vapors condense sometimes and consolidate and you get a few drips. I tend t get them after running the super moto bike and after slow single track riding on the WR.


You may also want to confirmthe float is not set too high.

Thanks for the info...I will give it a go on the float needle test...thanks again.

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