KTM 400 exc leaking gas

[rmx-250]

I parked my bike after riding around for a bit and when I came back after letting it sit for ten minutes there was s small amount of gas on the ground. I traced it back to one of the tubes coming out of the carb that runs down and ends at the underside of the motor towards the rear. Can someone tell me why its all the sudden leaking gas? It never did this before and when I shut off the fuel and let it run off whats left in the lines I deson leak anymore.

 

[steve.emma]

common problem on the pre '07 RFS bikes was a worn/cracked o-ring that seals the fuel needle valve seat in the carb float bowl. the worn o-ring means the valve shuts off when the fuel level is correct but fuel leaks around the seat and into the bowl, this fuel then leaks out the carbs overflow pipe.
replace the o-ring = happy days.

p.s. merry xmas everyone!