Tiny black pieces around final drive magnetic plug

[suecanada]

Upon inspecting my final drive magnetic plug I found some tiny non-magnetic black pieces in the area under the crush washer. There are tiny recesses so I was cleaning thoroughly. They can be picked up by a pinhead so they are somewhat soft...not metal. Too hard to be rubber I think. Seem to have a ridge on one side when viewed under the 10X magnifier. Any ideas?  Hard to describe the location but if you look at a magnetic drain plug you will see the magnet is in the centre and there is an area around it that is slightly recessed.

After this discovery above, I used nhmaf's idea of installing a new O-ring on the outside of the brake actuating arm between the felt and the final drive casing. So far with one short ride...no leaks and no splashes of oil on the wheel rim. Any chance the tiny black specks on the mag. plug are old O-rings? Seal material?

Is there any way a tube, like some models have, could be retrofitted around the brake actuating arm on our 1983 bikes to get rid of those O-ring (s)?

[Rob Valdez 79 R65]

Seal material is what first came to mind.  I've never opened a final drive before, but that will soon change, as mine is leaking with great regularity.

Shortly after pulling into the Tech session in Ohio last Friday, I was told that it looked like I needed a new big seal in my final drive.  And I had new seals and gaskets back in my garage (150 miles distant).  
I could have had the work done there with help, darn it.

[Bob_Roller]

I had all three of my final drives opened up for seal replacement and one filler hole repair in the last 18 months .

I would say that the small lumps you found were old seal material from the brake camshaft .

[suecanada]

In order to test whether this is old seal or o-ring material I'll just ride the bike until I ascertain whether I have any leakage that requires attention. For all I know this material has been on that plug for some time and represents an old O-ring from before I replaced them. Am I right that the outer seal on the left side is an easy job and the inner seal is a lot harder job? May need a pro?

[nhmaf]

I think that one can replace the inner seal (#2 in this picture, I believe) as long as you are careful about taking the parts out and putting them back in exactly the same order - like the transmissions, the final drives are shimmed and there are several shims of varying thicknesses which are used to take up the excess free play in the assembly and account for manufacturing tolerances, wear, etc.   If your final drive is otherwise working fine, you want to make sure the shims go back in the proper order/location.  To replace the inner seal, you'll have to take the left cover off and remove the crown gear, so you may as well replace the large seal which goes around the spline drive (cover spline teeth with duct tape or electrical tape to prevent cutting seal) as well as the paper gasket that goes between the 'cover' and the final drive housing.

http://www.suraklyn.com/r65_forum_gallery/displayimage.php?pid=574&fullsize=1


oops, that didn't work well,    grrrrr @#$%

Well, this is where I found the exploded diagram from anyhow:
http://www.maxbmwmotorcycles.com/fiche/DiagramsMain.aspx?vid=51899&rnd=03252011