Hi, first of all thanks for letting me join, Thomas my name from sunny Texas. I run into an interesting issue with the carb of my daughter her 2007 KLX250H (or S I guess) leaking from the carb and really having a tough time to start Taking it apart, float is working fine, replaced the fuel needle and cleaned the whole carb, all needles and bowl, new gaskets. However, it started great right after but sitting for a couple of days, it will not start, and leaving the petcock open will slowly leak at the overflow. Might be the needle valve seat but it's not replaceable. To make it short, I tried purchasing a new carb from ebay, as a OEM is too expensive for her, and I could not find a place having it anyway. All the ones that are listed as compatible do not have the throttle positioning sensor mount and are capped off, without even having attachment points for it.....what am I missing as I run out of ideas. Thank you....

 

Turn the gas off and run the bowl dry at the last ride of the day, I don't see a problem.

 

Yes, turn gas off using tank petcock and let it idle until it dies.