My bike is a /7, so I might be off - did you replace the washer inside the fork leg (on the bottom of the damper tube), or just the external washer under the nut?  To my knowledge, it’s the internal washer that is actually the seal.  If you haven’t been in there, there is also a hard plastic bumper ring that resides at the bottom of the fork leg. These typically decompose into a broken-gooey-mess over the years. I’d plan to replace those as well.

I see a first fork rebuild in my future. thanks for the info.

chuck

Trying to share a picture of the sealing washer on the damper tube. Red arrow. Had my sliders off to install new fork seals at the time. 

If you saw the previous post*, R75/5 with weeping left fork. Thank you to David Elkow for your post and picture, to Max BMW parts file, and my Haynes manual.

Laying under the fork, i saw 2 ways for oil to leak. Through the small nut and washer at the center or through the large 30mm end cap threads. I cleaned and dried the rubber plug and put it back on the bottom of the fork. The next day i took it off, inside of the plug bone dry, the outside lip, of the plug, was wet with oil. The 30mm end cap threads were weeping.

The manual shows it is torqued to 85ft-lb and i don't have a 30mm socket. I got out my adjustable impact wrench (adjustable wrench and 2.5 lb sledge), yea I know, had the granddaughter sit on the bike and hold the handlebars. I gave my iimpact wrench a tap. Then I tapped harder and the nut turned. The weeping was a loose end cap. I tightened it a 1/4 turn and will buy a 30mm to torque correctly.

thanks all

chuck

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