Clutch mystery part

[dave n]

My 1992 K100RS has been leaking more & more eng oil from bellhousing drain hole - so apart it came.

Upon removing the clutch hub nut & compression washer I found this additional washer before o-ring - .044 thickness. (see pic - 2nd from rt)

This only being my third K bike clutch disassembly I had never seen this extra washer before.

Looking thru "RealOEM" clutch parts diagrams it's not shown in any of the K75,100,1100,1200 breakdowns either.

Now the question; should I put it back in or leave it out - with a new o-ring of course.

http://www.maxbmwmotorcycles.com/fiche/DiagramsMain.aspx?vid=51709&rnd=03252011

Also was surprised to find the thrust washer (#10) is plastic - 1.25mm and $30.00 !!! - it will go back in.

I will reuse #8 & 9 unless I get many no votes.

Yes that's some sort of sealant on o-ring - doubt if it came from factory this way.

I don't have much info on history of bike; 54000 showing; had been sitting for 3-4 years.

 ???






 

[Rick G]

Only thing I can come up with is that someone wanted to give the O Ring a bit more compression because it had leaked previously when it was in good condition.
Maybe the housing was remachined at some time due to damage and it was needed to take up the space.

[Ocelot]

Cripes. Here's what it is: Spoor of the DPO.

[frankenduck]

I've taken a bunch of  Ks apart and have never seen anything but the thrust washer and clutch nut.

PS: If you're going to attempt to link to a parts diagram please do not link to sites like MAX BMW that use frames for their parts fiche.  The link you posted goes  to the index of the parts fiche which is not very useful.  Use something like RealOEM which does not use frames and will take to an actual specific parts diagram.

Like so: http://www.realoem.com/bmw/showparts.do?model=0533&mospid=51709&btnr=21_0251&hg=21&fg=21

[jimmyd]

Anyone know which size thrust waser is the correxct thickness. Minw was missing as well and before I put this puppy back running I'm leaving no stone unturned.
For the couple dollars difference I think I should go with the thicker one,but can't imagine it will make that much difference.

Any feedback?

[frankenduck]

It's not a plain flat thrust washer.