R26 clutch plate friction plate Kupplungsfriktionsplatte

[bwprice100]

Hi All

I have looked everywhere but I cannot find what the new thickness and minimum thickness of the clutch friction plate (Kupplungsfriktionsplatte) on my R26; can anybody help? I think I should be able to re-use the original clutch parts but I would like to check how much wear it has had.

Also the clutch actuating rod (druckstange) just seems to push into a 'V' shaped depression on the engine outer clutch plate. Should there be something else there or is just sufficient to put a small amount of lubrication there. Or does the actuating rod turn with the engine?

Brian

[bwprice100]

[Rütz]

Hi Brian,
new is 5 mm. It can be used until min. 3 mm, i think.
Because the wear is not plane, it should -in case- always be exchanged together with the clutch ring and as possible also with the plate.

Your pushrod assemble seems to be correct. And so are your conclusions (small amount of lubrication, i.E. MoS2 etc...).

Ruetz

[rolf.soler]

Very truly small minuscule amount of lubricant, if at all. Lubricant is following cetrifugal forces and gets between friction plate and ring, causing a slipping clutch. Better nothing. There is no part there in between

[mekgyver]

with the very long driving-time i had with my R25/3,
i can say: 4,5mm is the minimum

mek

[Rütz]

Meeek!
The /3 has a different clutch, its friktionplate is 7 mm new and the wear out limit is 5 mm. So: No wonder.

[rolf.soler]

What ? Are you sure ? I thought that 25/3, 26 and 27 all have the same clutch (plate spring), and friction disk is 5 mm
The R24, 25 and 25/2 have a different clutch (3 springs) and a 7 mm friction disk

[sigi_rs]

Good morning, rolf,

that's correct. The spring is different, too.

Greetings
Jörg

[Rütz]

Yes, that's the reason why Daniel (Güllepumpe) had to shorten his gearbox driveshaft.

R25/3 had the "Prototype" plate spring clutch (same principle, but different parts):
Deeper Flywheel + higher plate spring + thicker friktion plate -> alltogether it's roundabout 5mm "longer" than R26/27 and the gearbox driveshaft is/has to be shorter.

Ruetz

[bwprice100]

Hi Brian,
new is 5 mm. It can be used until min. 3 mm, i think.
Because the wear is not plane, it should -in case- always be exchanged together with the clutch ring and as possible also with the plate.

Your pushrod assemble seems to be correct. And so are your conclusions (small amount of lubrication, i.E. MoS2 etc...).

Ruetz

Thanks Ruetz

It measures 4.8 mm so a clean up and refit I think.

Brian

[rolf.soler]

Yes, that's the reason why Daniel (Güllepumpe) had to shorten his gearbox driveshaft.

R25/3 had the "Prototype" plate spring clutch (same principle, but different parts):
Deeper Flywheel + higher plate spring + thicker friktion plate -> alltogether it's roundabout 5mm "longer" than R26/27 and the gearbox driveshaft is/has to be shorter.

Ruetz

Aha. But all the dealers sell one friction disk only for R25/3, R26, R27, that is part Nr. 21 21 0 070 000 and 5 mm thick; whereas the other one-cylinder friction disk is for R24, 25 and 25/2, has part Nr. 21 21 0 070 000 and is 7 mm....So are they just beeing their stupid themselves or are they maybe right to sell the 5 mm disk for 25/3 ?
The other parts (flywheel, clutch plate and plate spring are different between R25/3 vs. 26/27; but friction disk and and clutch ring are the same for 25/3 as for 26, 27 - according to the parts catalogue of 3 dealers..(Huggett, Uli + Stemler)
Also with the 4,8 mm Brian measured, it guess it was more likely a 5 mm disk (to bring down a 7 mm to 4,8 mm takes some time + heavy use).
@Brian: Question: was the clutch operating well before you disassembled it ? If so, I guess you can leave it, if the lining is not cracked, and if the clutch ring not bent. If nobody alive remembers when the bike last moved, then maybe better replace it (disk and ring)
But even if you put it together as it is and later realize that the clutch is bad after all, its not a big thing to change.
Better save the money for now for a non - Chinese generator

[bwprice100]

@Brian: Question: was the clutch operating well before you disassembled it ? If so, I guess you can leave it, if the lining is not cracked, and if the clutch ring not bent. If nobody alive remembers when the bike last moved, then maybe better replace it (disk and ring)
But even if you put it together as it is and later realize that the clutch is bad after all, its not a big thing to change.
Better save the money for now for a non - Chinese generator

I have no history of the bike running as I had it in 'kit form'
Looking at the condition, it is dry, with even wear and shine to the metal parts, with no evidence of juddering. There are no visible cracks or distortion.
So I think I will fit and see and as you say it won't be too diffcult to change if there is a problem.

Brian

[Rütz]

...right to sell the 5 mm disk for 25/3..

Puhh, shit, sorry.
Think i was wrong (once again) and should better more confine to "my field" (R26/27).
Nevertheless 5 mm is right for R26/27 and 4,8 mm should be sufficient for many tenthousand further km..