Re: Occasional carby leak
Are you using an in-line fuel filter? This sounds like crud getting caught in the float valve. The kit tanks are notorious for having rust, dirt and scale in them. They need to be cleaned and flushed before installation and then a good in-line filter installed between the tank and carburetor.
Also it is always a good idea to shut off the fuel petcock when the bike is parked. Even with a properly working float valve fuel can seep, especially if the petcock doesn't shut off completely, and give you the condition you describe.
Check the petcock to see if it completely closes in the off position.
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