Found a great little tech tip on the Airheads Beemer club page on Facebook. It mentioned the annual inspection of your final drive on the rear wheel of /5 /6 /7 airheads. I know there are several BMW Airhead guys in our Vintage and Cafe group, so I thought I’d share this maintenance reminder. Visit the site, he has a lot of good information on it.
This hole can get plugged up. It often gets plugged up with excessive spline grease. If the seal is leaking badly and the hole is plugged up, the oil will run over the lip, down and get on the brake shoes. They suggest that once a year it get blown out with compressed air. One can use a wire, but the hole isn’t very straight and the wire probably won’t get through a clear hole. Sometimes a pipe cleaner will work too.
Read the full article here: http://w6rec.com/duane/bmw/finaldrive/