All of my Concours bikes developed a tiny bit of a leak in the front pinion of the final gear housing. After taking the time to fix it right once, I decided not worry about it. That little bit of gear lube forward of the "O" ring does not hurt anything. I put a thin film of black rtv on the flange where the four studs hold the final drive to the swing arm to keep thing clean at that joint. Tens of thousands of miles later, no problems, and the gear lube level does not go down. (if I was having to top up the lube in the final drive housing in between the annual change interval, I would fix it right)