Noticed a leak of oil from the Final Drive cap - I had wiped the oil and dirt away before this pic - bike was at the BMW Service Center in Seoul for 4 weeks, then out of action in the garage A clean, healthy cap will spin freely over the seal. This one is sticky and gunked up with dirt and oil. Pop the cap with a small screwdriver. Use care - the final drive material is pretty soft - magnesium I think. Rocks and tipovers will ding it up fast. ** edit ** Remove the lock ring. Pop it out with an awl or very small flathead screw driver. Don't try to pull the seal before removing lock ring. ** ** Now the fun part. Use a small drill bit to drill a hole in the seal. Use one of the existing dimples in the seal as a guide. The seal is made of rubber over a thin metal plate or disc - so you have to push. Use a nice sharp drill bit Then insert a sheet metal screw - not too big. You only need to turn it a few times so that it has a good grip on the seal. There is actually a few millimeters of space on the other side, so you have some room to work. Pull evenly, firmly, in a vector perpendicular to the shaft drive - straight out. The seal will come out evenly. It won't tear or crease. Once it comes out a bit, you can help it with your fingers. Looks worse than it is - There was a gritty muddy sludge oozing out of the seal space. I spent a few minutes wiping it clean. After that, only clean oil was weeping out. You will be able to see the outer roller bearings. There is another set of bearings on the other side of the wall, then another oil seal much like the one you just pulled. See MaxBMWMotorcycles for the diagrams. You can see the screw (blurry) in the seal, poking out the other side 4mm or so. Even with the screw inserted that far, there was no marking or scoring on the inner surfaces. Listen to the bearings - I removed the brake caliper and spun the wheel, listening to the bearings with a stethoscope. Sound was ok, no nasty grating or uneven metallic sounds. Installing new seal - I installed a new seal, using the old seal as a template over top, and a rubber block, to gently tamp it in place. I let it sit for an hour or so; no new weeping. Then installed a new cap. Entire operation could be done in 20 minutes. I spent 2 hours or so, really looking at it, cleaning things, and watching for leaks.
