When I put the bike together a few years ago for my long trip, I went around looking for a reason for, and solution to, gear lube being forced out of the rear drive seal and onto the rim. I ended up drilling a hole in the filler plug and pressing a grease zerk with ball removed into the hole, and running 3-4 feet of tubing up the swingarm and along the frame, exiting by the rear turn signal. In the main it was ok, but at high speeds and unknown distances it still emptied about half the gear oil