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ericowen21@hotm...
ericowen21@hotmail.com's picture
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argentina
Joined: 07/26/2016
Posts: 1

I have recently bought a bmw r11 which had some restoration on it.
Clutch disc pads were remade but apparently they are too thick. When I active the cluth there is still some fricction between them.

Does anyone has an idea of how thick should the friction substrate be???

Thanks in advance.

Eric Owen from Argentina

Bruce Frey
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VBMWMO #6316
Texas Hill Country, USA
Joined: 10/27/2006
Posts: 574
I'm not sure how the R11

I'm not sure how the R11 differs from the R12, but clutch disks that are too thick seem to be a common R12 problem, too.

My first set from Switzerland were way too thick. Since I wanted to put it back together ASAP I sourced another pair in the USA which were just a tiny bit too thick. The clutch drags, just like yours. A replacement set that are said to be within spec arrived from Switzerland (at no cost) and are in a storage box awaiting installation, which is a PITA. I really don't want any more practice.

I'll look for the box and measure them.....although again, I am not sure how the R11 and R12 disks differ, if any.

I should add that getting the clutch adjustments on the R12 set to maximize the travel is a bit finicky, so make sure your adjustments are correct. It doesn't take much to make the difference. Make sure those are correct before opening it up.

Stay tuned for the measurement.

Cheers,

Bruce

Bruce Frey
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VBMWMO #6316
Texas Hill Country, USA
Joined: 10/27/2006
Posts: 574
I resurrected some old emails

I resurrected some old emails on the subject. My R12 has been in storage for a number of years while I was working in Canada and my memory is not what it used to be.

Here is what I know (which is not much). Huggett says the clutch disks for an R12 should be 6mm thick, but most reproductions are too thick. My first set was well over 7mm, the second just over 6.

Vech advises that he uses hardened lock washers over the over the posts as a spacer to compensate for the over-thick plates. I did this and it sort of works....I still have a bit of drag that I have not been able to adjust out. I'm not sure if I should have used double washers or if there is another issue, but when I get to it, Ill go through the adjustments again before I pull it apart.

I'll still dig out the replacement disks to see how thick they are.

Cheers, Bruce

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