I have an '03 UC, and chased a leak that I thought was coming from the primary for a few months!! Fiddled with the drain plug, replaced the primary cover gasket, replaced the main inner primary seal. NADA!!
Because it turned out to be the tranny J-tube vent line blowing oil mist on the back of the inner primary and that flowing down to the low spot (right around the drain plug) on the inner primary/primary cover. Now I am not sure if the Dynas have that silly little J-tube coming off the nipple on the tranny top cover like the UCs do, but if you have one, try getting a couple of feet of tubing at the auto-part store and route that back over the tranny by the starter and out to the bottom of the bike on the right side (there is a small fuel drain line over there now probably). Wash the bike up real well especially there between the tranny and the inner primary and see what happens.
TQ