rear differential seal

Hello everyone... I haven't visited much lately. after a long break for racing season... I'm back to the restoration of the 1971 R75/5

so this bike has been off the road for 26 years.

I start my question that way so that I can explain why I'm digging so deep
the bike was apparently taken off the road, for the reason of a pinched points wire
but it sat... in 3 different states...


all of the rubber is rotten
I've taken the bike down to nuts and bolts
I've replaced all of the motor seals

My question today:
what do I want to do with the rear differential

I've read snowbumms documents about fluid transfer

I don't know if my seal is bad... but based on the findings of all of the other seals... I would guess its dried up, old, and crusty

I searched the forum without success
would folks recommend addressing this seal now, so as to avoid a big mess in the future?
the swingarm.. everything... is removed from the frame.
is there a how to thread or article?

I see the cycle works tools.
I'm worried about messing up the pre-set on things... digging into something I'm not familiar with

what input do you all have.
surely someone has some hands on experience I could benefit from

thanks in advance
brant in Colorado

I didn't find any related videos, but Matt Parkhouse has an article in the September 2016 ON about final drives. Might a place to check out.

20774 said:

I didn't find any related videos, but Matt Parkhouse has an article in the September 2016 ON about final drives. Might a place to check out.

Click to expand...

good Info as Always sir!

I only joined MOA in 2019

I'll ask around
Brooks lives within driving distance
I'll ask to see if I can find the article

thanks!

anyone else have experience with this job?
brant

The later ON issues are online on the main MOA webpage. Go to bmwmoa.org, click on owners new and archives. In the drop down box click on 2016 and find the issue.

You might also check with Brook's online blogs...he might have done this before.

Even Matt recommends Hansen's for final drive work:

https://www.hansensmc.com/--spline-repair

I found this helpful when replacing the pinion gear seal in my 1973 75/5.

https://www.youtube.com/watch?v=9rw6IQcBnXQ

cwroady said:

I found this helpful when replacing the pinion gear seal in my 1973 75/5.

https://www.youtube.com/watch?v=9rw6IQcBnXQ

Click to expand...

This is just one of a series of tutorials on the R90/6 series by Boxer2Valve:

http://www.boxer2valve.com/bmw/R90slash6Tutorials.html

Perfect...
thanks you all!

the video is exactly what I was looking for

I went through all of brooks site, but didn't see that he has documented this job

the video gives me courage to move forward
thanks everyone!

brant