Reviewed all the H-D XL parts books from 1954 to 1999 trying to find what year the front aluminum laced wheel hub changed from the large rotor bolt circle diameter to the smaller rotor bolt circle diameter.
In the 1954 to 1978 parts book, the first flanged type aluminum front wheel hub appeared as p/n 43600-73 after the previous cupped end steel hub.
This hub incorporates five ,3/8"-18 threaded lugs on the rotor bolt circle with mechanical cable speedometer mechanism mounted on the axle.
In the 1984 to 1985 parts book the hub part number was changed to 43619-84, but the same graphic depiction of the previous hub,43600-73, is shown in the exploded parts view.
Followed this same 43600 hub part number from 1985 to 1999 covering eight different sportswriter parts books.
All the graphic depictions of this 43600 hub from 1984 to 1999, used the same graphic as the hub p/n 43600-73.

Trying to verify what year the front wheel hub changed from the large bolt circle diameter with the 3/8"-18 threaded rotor lugs to the smaller bolt circle diameter, 5/16"-18, threaded rotor mounting holes.
Maybe the change occurred in 1984 with the part number change, but the parts book graphic does not reflect it.
Maybe the parts book graphic was not updated.

 

1984...pictures aren't always correct.