The block under the carb is sometime not made right..Lay the carb gasket on the block and check to see that the pulse passage is milled far enough around to let the pulse go through the gasket..I had one here last week that was about 1/16 short and the pulse would not reach the matching hole in the carb..
The carb needles are usually about 1 1/3 to 1 1/2 open on both when set right...
The carb disc is machined with a bevel on the edge to completely close..If it's wrong it might not close off all the way...[8D]
Check the lever that lifts the inlet needle, it should be flush with the casting..A straightedge across the casting next to it should just barely touch the end of the lever...
Check the gaskets on the carb...The diaphragm with the metal center goes on TOP of the gasket on that side, the diaphragm on the other side goes UNDER the gasket...