Hmm... what is this thing?

[scootnewb]

I noticed the Keihin carb I have on there now does not have that screw in there. It is just open IIRC.

 I thought the drain was the one that connects to the hose with the spring. 

Thanks.

[GrumpyUnk]

There are two styles,it seems. One has the screw, and the 'armored' tube, with a shutoff at the bottom of the tube. the other has a plain tube, and a sutoff at the bottom of the float bowl.
If you loosen the screw in the picture, you will drain the float bowl. The other style has that valve open all the time, and allows draining over ty the CVT cover. It is easier to use, and pointed to markets where the engine may sit for a while, unused, and need to have fuel removed for storage. The one shown is harder to drain.
tom