first rule out the drain screw - shut the fuel petcock off, let the bike sit a while, then with the carb still on the bike take out the 4 bowl screws and remove the bowl to see if it is empty. if its empty the drain screw is leaking, if its not then the gas coming from the tube is indeed from the overflow. If you determine the screw is leaking, that may be a little tricky to fix, the screw just seats into the bowl metal, and if grit got in it and has gouged where it seats then maybe you can get the grit out and put enough torque on the screw to reseat and seal, worst case scenario replace the bowl along with a new screw.

so when you go to swap that o-ring (don't remember size, but it is metric) also check that needle very close and clean the seat well, but do not put even the tiniest scratch on that seat, and if you see the slightest almost microscopic scratch or nick in the seat then replace it. if the needle has a well defined groove all the way around it where it seats, go ahead and replace it. sometimes you can look at a needle and seat til your blue in the face and swear it look sperfect, but still never a good seal until you just break down and drop $20 to swap them both, along with that o-ring. one thing is for sure, if the float is adjusted right and it keeps overflowing, the ultimate positive fix is replacement of needle, seat, and o-ring.

Lube that O-ring well prior to install so it doesn't get scratched during insertion.

 

Thanks agian hightower!! you have been very helpfull, im gonna order float bowl,o-ring drain screw and try it all over agian. What should i use to lube that o-ring?

 

don't forget to get the float level set just right, 10mm like eaglecollector said.
did you determine if it was the drain leaking, or overflow?
if its the drain, then yes to the screw and bowl, but if its overflow then yes to the needle valve, brass seat, and o-ring that surrounds the seat. use grease on the o-ring