[SkinnyG]

Mine is just as you see above.

The connecting hose at the air horn can be simple rubber. The connecting hose at the choke housing should be silicone so it doesn't melt (it's going to get very hot).

You should have a gasket for the bakelite choke cover, as well as a wee plastic double-spigot-spacer that connects between the choke housing and the carb body (the seal for the vacuum source).

Check all vacuum ports on the carb and make sure none of them are unplugged (don't forget the one at the back of the carb base for the hot air riser on the air filter).

Make sure the secondaries close all the way.

Make sure the primaries are as closed as you can get them (you don't have a rowdy cam, do you?).

When you assembled it, did you check for warpage at the air horn as well as the carb body? These are almost always warped by people over-tightening the carb bolts. Another potential source for leaks.