Copper washers

In my continuous and nearly finished quest to end the oil seepage on my KZ1100 I have come to find what I think is my last intermittent oil leak. After riding a while I'm noticing a little dampness around the left side rear head stud (outside) Are these the pressure oil ports to the head? I know there are oil passages on outside studs but not sure which are oil in and drain. Thanks

This might help

Thanks...I just replaced all four washers yesterday. kinda weird though thy would seep then I would wipe the head off and they wouldnt seep for maybe a couple of weeks again..