I'm sorry but what I said earlier might not of been plain enough. Motorcycle oils are usually not the right thing for an Airhead. Motorcycle oils are made to work with a wet clutch which is not used on an Airhead.
Our bikes have what is called a flat tappet cam shaft. Because of this we need Zinc. The element Zinc. It is found in motor oils under the name of ZDDP. Modern oils do not have ZDDP because of problems it causes with catalytic converters. Some oils made and advertized for older vehicles may have ZDDP in them. Try Google.
If you don't know of the ZDDP content of the oil you are using you can do what I do. I use BMW 20/50 wt from the dealer.
These engines develop severe problems if the wrong oil is used.