75 850 ES clutch
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Kevin,
During my Mk3 rebuild last year I, like you, reused the existing friction plates, since they appeared to only need cleaning. During the debug phase, I found, like you, that I could not "clear" the clutch prior to starting. That is, with the clutch pulled in, it took several full kicks to release the plates. I found that old plates, in spite of their appearance, were unusable and unreclaimable, and finally, after many cleanings, spent the 60 bucks and installed new friction plates. Problem solved; the clutch clears on the first kick. My only regret was spending as much time as I did trying to reclaim the existing plates. I installed the Dave Comeau rod nut as well. Its been a year now and I never think about the clutch. Do yourself a favor and install new plates.
ATM is a poor choice in the primary of a Mk3. The hydraulic adjusters need an oil with more heft, like 20/50.
During my Mk3 rebuild last year I, like you, reused the existing friction plates, since they appeared to only need cleaning. During the debug phase, I found, like you, that I could not "clear" the clutch prior to starting. That is, with the clutch pulled in, it took several full kicks to release the plates. I found that old plates, in spite of their appearance, were unusable and unreclaimable, and finally, after many cleanings, spent the 60 bucks and installed new friction plates. Problem solved; the clutch clears on the first kick. My only regret was spending as much time as I did trying to reclaim the existing plates. I installed the Dave Comeau rod nut as well. Its been a year now and I never think about the clutch. Do yourself a favor and install new plates.
ATM is a poor choice in the primary of a Mk3. The hydraulic adjusters need an oil with more heft, like 20/50.
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Make that ATF, not ATM. Must have cash on my mind.
click
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Hi Lads,
I really appreciate all your help & input on this.
I think I have found the cause of the problem, as usual it was my rushing through things as I had it in my head all I needed to do was clean the plates & all would be well.
Just some stats before the pics.
The combined stack height of the 5 bronze & 5 plain plates is 1.043 (without the thicker pressure plate)
Stack height with 5 bronze & 4 plain plates is 0.958 (without the thicker pressure plate)
Here is a pic of all 10 plates (5 bronze & 5 plain in the clutch basket)
OK now the pics, you guys can tell me if the wear on the centre splines is acceptable or not (I think the answer will be not!)
I really appreciate all your help & input on this.
I think I have found the cause of the problem, as usual it was my rushing through things as I had it in my head all I needed to do was clean the plates & all would be well.
Just some stats before the pics.
The combined stack height of the 5 bronze & 5 plain plates is 1.043 (without the thicker pressure plate)
Stack height with 5 bronze & 4 plain plates is 0.958 (without the thicker pressure plate)
Here is a pic of all 10 plates (5 bronze & 5 plain in the clutch basket)
OK now the pics, you guys can tell me if the wear on the centre splines is acceptable or not (I think the answer will be not!)
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The lifter arm looks OK.
The centre could be worn, but I doubt it is as bad as mine was (see photo, back on page 1) and that didn't cause any drag problems if the engine wasn't running.
But, I do suggest you try it without that extra plain plate?
The centre could be worn, but I doubt it is as bad as mine was (see photo, back on page 1) and that didn't cause any drag problems if the engine wasn't running.
But, I do suggest you try it without that extra plain plate?
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click said:
http://www.oldbritts.com/ob_clutch_info.html
"850cc:
Friction plate is: 0.121”
Plain plate is: approximately 0.080"
Pressure plate is: 0.102”
Total clutch plate thicknesses (5 friction, 4 plain and 1 pressure) is: 1.027” "
(original bronze plates seem to be slightly thicker at .125" compared to the latest AN bronze plates.)
click
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chris plant said:
Hi Chris,
I might owe you an apology :roll:
I tested the clutch as L.A.B. suggested with the extra plain plate removed but it was still the same.
I then remembered what you had said & removed all the clutch plates & attempted the 'test' I was doing to see if the clutch plates where sticking (bike in gear, clutch pulled in, rear brake applied & kick the bike over) and guess what . . . . exactly the same, rear wheel moves under a lot of pressure from the kickstart!!!
Obviously the gearbox is directly connected through the front sprocket to the rear wheel via the chain when in gear regardless of the clutch.
It's what you where saying above, the test I've been doing is flawed.
The only true test is to put everything back together, start her up & see what happens!
As I said the 'test' I was doing gave the impression the clutch was grabbing but it cannot be the clutch when I've removed it!!
Silly mistake on my behalf.
Is my logic correct? Any comments?
Kevin
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L.A.B. said:
swooshdave said:
As someone said earlier (it may have been me) put it in neutral. Then kick it. (Way back on page 3...)
Hortons Norton
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Never mind I should have read the whole post. 
click
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L.A.B. said:
Hi L.A.B. and everybody else!,
OK might have been a bit of mis-communication on my side, the 'test' I've been doing all along is with the bike in gear.
I'll need to button everything up & start the bike or at least put it in gear, pull the clutch in & push the bike.
What I'll also try is put the clutch back on, pull the clutch in with the bike in gear & see if I can turn the rear wheel, this should be a true test to see if the clutch is grabbing.
Kevin
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