Working on my 85 K100 RT. A recent under body (of the bike) inspection revealed a coating of that black oily paste that is common with a slow, very slow seepage type of leak. It is on the underside of the swing arm, above the clutch actuator. It is not leaking, showing around the seam between the engine and trans. It doesn't drip, just a fuzzy coat of diry black oil. it is very isolated to just above the clutch actuator. I'll try to post a picture.