Timing problem

The is a screw that is under the carb that controls how far the throttle blade is open.

The carburetor came to me used with this set up strange. The throttle blades were not closed, they were more open. Messed with that screw to close them. I didn't get them too tight.

I also didn't know how to properly adjust that screw.
Is this the t port sync?


I'll take it back off and clean it. So far I've gotten all the fuel out of the lines. I'm concerned about residual build up in the lines and the fuel pump. Might not be a problem. Not sure yet.