Clutch Basket Bearing Recommendations? 860GT

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herbg
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by herbg » Fri Aug 25, 2017 12:03 pm

Wow ... this board is so helpful!! Great sleuthing everyone!! Your timing is perfect as I am right in the middle of taking the clutch springs out and will replace them with the originals!

I noticed that section in Ian Falloon's book too and didn't think much of it. When I purchased the Surflex Modifica S1425 competition clutch, I naturally used the 6 springs that came with the kit! Of course, there was no reference that these springs only work with clutch hub 0799.16.590 .

Live and learn indeed!

Old905Duc, with this in mind, would you still replace the Brancato extended clutch lever?

Thanks,
Herb...
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

herbg
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by herbg » Fri Aug 25, 2017 1:07 pm

Upon further examination, it appeared that 3 of the clutch springs and spring cups were binding against the HD pressure plate.

The Gowanloch HD pressure plate is just the slightest bit offset. No matter where I rotate the pressure plate, I cannot get it to perfectly line up against the screw bosses so that they are centered in the opening.

The OEM pressure plate is also not perfectly centered but there's tolerance that I can slide the spring cups in without binding. So, in the interests of the KISS principle, I am reinstalling the OEM pressure plate.

Not sure if you can see the slight offset in the holes of the two pressure plates from my photos attached.

Anyone run into this before?

Cheers,

Herb...
Gowanloch HD Pressure Plate.jpg
OEM Pressure Plate.jpg
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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Old905Duc
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Old905Duc » Fri Aug 25, 2017 1:50 pm

Herb, concerning the Brancato extended clutch arm I would leave it installed for now (if not already removed) and see how the clutch works after re-installing the original clutch springs. The problem that I had with the extended clutch arm was a slight drag (incomplete disengagement) that made it very hard to find neutral at a stop. This was after very careful clutch adjustment and modification of the handlebar clutch lever to slightly increase total clutch throw. Since I was using the intermediate 22Kg clutch springs (not the heavy duty 26Kg) I figured that the clutch pull would be livable although still "manly".

Never the less a lighter clutch pull is always desirable. So, I think you should give it a try. Maybe bike-to-bike tolerances will work in your favor. If you have similar problems selecting neutral you can always re-install the original lever as a fallback.

Old905Duc

herbg
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by herbg » Fri Aug 25, 2017 2:28 pm

Yes, I'm with you. I'm leaving the Brancato lever in place as the clutch action is noticeably lighter now that the original (non-binding) springs are back.
Question: How much torque is recommended on the screws holding the clutch springs in?

Now, I'm trying to get all the slack out of the cable so that the clutch is fully engaged when the clutch lever at the handlebar is pulled in. Had to back off the adjustment screw at the handlebar, extend the clutch cable bracket at the engine as far back as possible, and finally turn in the clutch rod/ball screw quite a bit.

I think I am close to getting this fixed.
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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Old905Duc
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Old905Duc » Fri Aug 25, 2017 3:08 pm

Unfortunately neither my factory manual nor my Hayne's manual specify the torque value for the clutch spring screws. So, I just tightened by hand being careful to get them firmly seated without straining the threads. I guess one could query the Web for typical torque values of a 5mm screw in a mating steel part(?). Maybe others in the forum have suggestions? Ian's "Bible"?

Old905Duc

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Craig in France
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Craig in France » Fri Aug 25, 2017 11:35 pm

herbg wrote:
Fri Aug 25, 2017 2:28 pm
Question: How much torque is recommended on the screws holding the clutch springs in?
As Old905Duc: I can't remember having seen a spec from Ducati (the company was never very forthcoming about torque values :shock: .)

So tight, but not too much ... :-D

Seriously: they're not really doing a 'Job of work,' so don't go overboard. 'Screwdriver tight' is fine.

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Re: Clutch Basket Bearing Recommendations? 860GT

Post by ducadini » Sat Aug 26, 2017 12:13 am

Isn't there a list with "standard" torques in the back of the manual ?
When all the adjustments run out of range, just put a slightly longer rod in the gearbox-shaft.
Keep in mind that the hole through the shaft has two different diameters.
All other Ducs had about the same system so You could score some parts of those.
ciao
ducadini
Nego i ricordi peggiori
Richiamo i migliori pensieri

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Craig in France
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Craig in France » Sun Aug 27, 2017 2:53 am

ducadini wrote:
Sat Aug 26, 2017 12:13 am
Isn't there a list with "standard" torques in the back of the manual ?
As far as I know ...
The first time that such a thing appeared was in the 1977 Darmah owner's handbook:

Torque settings v1.jpg

And the first workshop manual that had a list (as such)* was the 1981 "900 Replica, 900 SS". It was even less comprehensive ... :shock:
* Before that, the few values that were given had to be found, buried somewhere within the text ...

Torque.jpg

herbg
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by herbg » Mon Sep 04, 2017 2:37 pm

So, I appear to be at a dead end. After reinstalling the original clutch springs and pressure plate, along with countless adjustments of the clutch cable at the handlebar and at the engine, as well as the ball & rod nut/screw, I can't seem to get the clutch to release when in gear???

When I engage 1st gear, pull the clutch lever in, I cannot get the rear wheel to spin - whether turning by hand or by trying to roll on the garage floor. Same thing with 2nd or 3rd gear.

Upon observing the pressure plate through the side case opening, I can see the pressure plate extending well beyond the spring screws. No amount of adjustment seems to help.

I can also observe the Brancato extended lever and it pulls about 3/4 of the way towards the engine.

So, I'm stuck ... is it the Brancato extended lever or something else I might have missed? By replacing a slipping clutch, I somehow have achieved the opposite - a fully engaged clutch even with the clutch lever fully engaged.

Any suggestions??
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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Old905Duc
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Old905Duc » Mon Sep 04, 2017 4:04 pm

Herb,
Sorry to hear that the clutch is still stuck! The only two things that I can think are: 1) the clutch plates are stuck together from inactivity, or 2) something is amiss in the clutch pack assembly. Item 1 can be addressed as Ducadini recommends by pulling in the clutch and kicking through several times until the clutch plates free up and disengage. I just tried this on my 860 which has not been started in a couple of weeks. Initially the clutch plates were stuck, but after a few kicks they freed up and the kick start lever disengaged from the engine. If you cannot free the clutch this way then something still must be wrong in the clutch pack. All I can recommend is to pull off the cover (again) and disassemble the clutch and carefully inspect. Note that the orientation of the friction and steel plates are important. The first friction plate is unique and has bent teeth which engage the hub splines. The teeth need to be pointing outward (toward the pressure plate). The rest of the friction disks are common and have straight teeth. The last steel plate is also unique and has bent tabs which need to face inwards. I have attached a clutch parts diagram below from the 900 SS Spare Parts manual on this site.
Ducati 900SS Clutch Diagram.jpg
I hope that his helps. Anyone else have any good ideas?

Old905Duc

herbg
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by herbg » Tue Sep 05, 2017 3:41 am

The clutch did free up when I kicked it over a few times when it was on the bike stand. So, I was confident it would be fine once I got it back on the ground. But when I tried rolling it on the floor or turning the wheel by hand, the clutch was still engaged.

I re-read the "FAQ: clutch pushrod order info" post and Spagjet said something which caught my attention:

"Clutch basket springs: sometimes the clutch doesn't seem like it's disengaging because the end clutch plate rises off the rest crooked. It has to be dead level or you need another few millimeteres of travel to get it to disengage enough (I've known people who thought they had a problem with their gearbox or selector box that fixed it with this idea). It's because the little springs are starting to collapse, you have to pull them out and make sure the are all exactly the right length. If they aren't the obvious way is to buy a new set but if there's only one (or two) that are more sagged than the rest you can try putting a packing washer under just those two and see if it improves the clutch. If there's three saggy ones and three (relatively) good ones you can arrange them good, bad, good, bad, etc right around and try and even it up that way. All you have to acheive is a dead level top clutch plate when it moves."

So, I wonder if the answer may be with the old springs I put back in - causing the pressure plate to rise unevenly?

Herb...
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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Old905Duc
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Old905Duc » Tue Sep 05, 2017 10:39 am

The fact that the clutch did free up somewhat when kicking over with the clutch pulled in is good news. Now it sounds like the clutch is not fully disengaging. This could be due to tilt in the pressure plate. It also could be due to insufficient lift from the longer (easy pull) clutch lever. To diagnose I guess you need to pull the cover and watch the pressure plate lift as you actuate the clutch lever. If the pressure plate is tilting then you need to move the springs around (trial and error) to alternate positions, or shim springs selectively to adjust so that it lifts evenly. My guess is that the longer clutch lever is contributing to this because the overall clutch throw is reduced which makes any tilting of the pressure plate even more critical. If the situation is not improved after eliminating pressure plate tilt, then I would recommend installing the original clutch lever to see if this allows full disengagement of the clutch.

Sounds like you are getting close, I hope!

Old905Duc

herbg
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by herbg » Tue Sep 05, 2017 1:24 pm

Another thought ... perhaps I should just buy new springs (the right length, this time) to eliminate any possibility of uneven spring strength?

Were these the springs you used when you discovered that you have the wrong length?

048016550 kit fits 450 singles & 860/900 twins, standard springs @ 22kg: https://store.bevelheaven.com/Engine-Re ... gs-Bevels/

Or, should I go for the heavier springs (really not sure what a heavier spring will give me other than more clutch lever resistance)?

079916550 kit fits 450 singles & 860/900 twins, heavy springs @ 26kg

Cheers,
Herb...
_________________________________
2013 Ducati 1200S Multistrada
1985 Ducati Mille S2
1978 Ducati 900 SS (Blue/Silver Borrani)
1972 Ducati 350 Desmo (Silver Shotgun)
1969 BMW R69S (Earles Fork)

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Old905Duc
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Re: Clutch Basket Bearing Recommendations? 860GT

Post by Old905Duc » Tue Sep 05, 2017 4:19 pm

Buying new fresh springs will give you a better starting point with even heights and full designed spring strength. The springs that worked for me were 048016550 (22Kg). Spring 079916550 (26Kg) DID NOT WORK in my application. They require a different center hub (per previous thread). I also suspect that they are the same (longer) springs that you received in your clutch kit. So, I would recommend that you go with 048016550 (22Kg).

Old905Duc

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