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Discussion Starter #1
Has anyone here worked on a wet clutch? I'm wondering if it is possible to insert spacers under the spring collars, or remove two of the plates to reduce spring pressure. It has got to the stage where I can't ride my GT anymore due to the pain in my left hand when using the clutch and a bike that can't be ridden is not much good.....
 

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Has anyone here worked on a wet clutch? I'm wondering if it is possible to insert spacers under the spring collars, or remove two of the plates to reduce spring pressure. It has got to the stage where I can't ride my GT anymore due to the pain in my left hand when using the clutch and a bike that can't be ridden is not much good.....


I’d love to know too. I have replaced the clutch master cylinder with an RCS17 as well as an Oberon clutch slave. It helped a bit but I wish it could be improved more.


Sent from my iPhone using Tapatalk
 

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Discussion Starter #3
I've just watched a video by Chris Kelly and interestingly, he states that the spring collars are different from model to model, which may be how Ducati changes the spring pressure from model to model. I've also had a thought about the springs fitted to say, the 620 or 800 engines - are they interchangeable with the 1000 models? Certainly the spring pressure on the 620 is a lot less because it has a lot less torque to deal with. Possibilities; I'm encouraged.
 

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People successfully remove springs from other models to reduce effort so that is probably an option. The difference in springs and collars is certainly a thing to look into. Compare part numbers to verify that they are different.
As far as the pain, i have started using CBD cream on my joints and wrists and i would recommend trying that. It has certainly made a big difference for me. Hemp cream also works for me, though it’s CBD content is lower, so is the price.
 

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Y'all gona laugh at me .....but.......... :grin2:
My Paul Smart is like that if the clutch fluid is old.

Have a Brembo RCS and Oberon slave. Have to change it every second season or I can barely ride it.
The difference with new fluid is huge.

Need bigger muscles :crying:

Laugh away............
 

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Have a chat with Thorsten Durbahn.
He makes cable conversion kits.
Durbahn Shop - Motor & Fahrwerk Kupplungsmechanik Seilzug
- unfortunately the page is only available in German.

From my experience with my take of the conversion during the past ten years, I would never go back to hydraulics.
51Nt to 33Nt with the same (1.7mm) travel of the pressure plate and immense improvement of the feel.
Not many points in aesthetics, mine, but I'll never get stranded because of a failed seal.
 

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Discussion Starter #7
I've never been impressed by hydraulics either. It feels to me that when a hydraulic clutch lever is pulled the pressure required remains constant, but a cable lever seems to require less pressure once the lever is back to the bars. Probably complete nonsense, but that is how it feels to me.
 

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Discussion Starter #8
I've ordered a gasket for the cover (can't abide all that silicone stuff) and I'm planning to shim out the pillars to reduce the spring pressure.
 

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the small block wet clutch is different to the big block wet clutch. of the small block wet clutches, the lighter clutch in the later 620 and s2r800 and later is the aptc clutch, which has a lot more plates than the others, lighter springs and the clamping ramp that is the applied torque bit. the older small block one has just as much lever effort as the big block or dry clutches.

there's lots of different springs from various models over the years.

you might be able to remove 2 of the springs, which will make a big difference. might make it slip too. have to suck and see. shimming out i think would need a lot to make the difference you're after.
 

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Discussion Starter #10
Removing two springs is not an option, because the clutch has only five springs, and what springs they are! They resemble valve springs.

I'll shim out the spring cups using various spacers and see how it feels. If I can't make a reasonable difference then it is goodbye. I'm thinking of getting an airhead BMW or a 620 Monster. I love the engines on both, but the Monster may be too cramped for me. What I really want is another bevel Ducati, but the prices are way too high.
 

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Discussion Starter #11
Shimming out the springs is not an option, as the screws are close to the inside of the clutch cover. I've managed to get a 1.5 mm washer under each screw but I don't think it has made any difference. Measuring the springs and comparing them to a spring chart, they appear to have a strength of 9nm; I have identified two possible alternatives, one of 8.25nm which probably would be too strong, and one of 6.55nm, which would be too weak; maybe Ducati just picked a spring off the shelf that did the job.

I was amazed when I took off the cover to see that the clutch on the 1000 appears to be the same size as the 500 Pantah, no wonder the spring pressure is so great. I would have thought that when they designed the 1000 engine that they would have increased the diameter of the clutch. When you compare it to other v twins it is obvious why Ducati needs such strong springs. I don't know if the hotter Ducatis like the 999 or 1098 use the same springs, when you consider how much more power they put through the clutch, you would think that the DS1000 wouldn't need as strong springs.
 

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the wet clutch is fairly unique. i forgot it only had 5 springs. barnett make a lot of springs, they may have something. give them the std spring dimensions and see if they can help. if you were getting serious you could get all the steel plates ground thinner and put an extra friction plate in.
 

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Spring companies many times have a spec spring catalog where you can match up what you need according to diameter, length , and rate, and material. ASC or Barnes Group ( same company) has one, I’m sure others do as well. Most of the springs in the catalog will be in stock for immediate delivery.
 

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Discussion Starter #14
I have succeeded in making the action a little lighter, by adding 1.5mm washers under the screw cups and the very scientific action of squashing the springs until coil-bound in the vice overnight. It is definitely lighter, but it will take a decent length ride to find out if there is any real improvement. If not, I will order the lighter spring option that I have found in a catalogue, and see how that goes; there is only one way to find out.....

If anyone wishes to work on a clutch, there is no need to drain the oil, just leave the bike on the side stand and no oil is lost. I used a gasket from Chris Kelly at CCW, which fitted properly and was a damn sight easier than messing about with sealant.
 

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Discussion Starter #16
No, I switched to an easy pull one about ten years ago, but recently replaced it with an Oberon in the hope that it might be more efficient, but it was no different. I could try a 30mm piston slave I suppose.
 

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The springs will normally lose a few percent the first time they’re pressed solid. If you want to reduce the length a little more, slip them over a bolt and nut them down solid, then 450 f ( no higher) for 10 minutes, then quench them in water ( or oil) right out of the oven until cold. They’ll lose a few percent of their preload but will not lose any more for a really long time. You can get a little higher tech with this if you want to measure the compressed length and quench them at a little less than their installed height. This procedure is used in the spring industry, where they initially make the spring too long and heat set and quench it to the designed load. They stay in spec way longer that way.
 

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I have succeeded in making the action a little lighter, by adding 1.5mm washers under the screw cups and the very scientific action of squashing the springs until coil-bound in the vice overnight. It is definitely lighter, but it will take a decent length ride to find out if there is any real improvement. If not, I will order the lighter spring option that I have found in a catalogue, and see how that goes; there is only one way to find out.....

If anyone wishes to work on a clutch, there is no need to drain the oil, just leave the bike on the side stand and no oil is lost. I used a gasket from Chris Kelly at CCW, which fitted properly and was a damn sight easier than messing about with sealant.
Duccout,

I'm very interested in trying this out. Could you kindly provide some pictures of where exactly you're installing those washers (sorry, I'm still a newbie)? I have a Brembo RCS17 master clutch cylinder as well as an Oberon slave cylinder and I'm still finding the clutch pull harder than I'd like compared to other newer bikes. Don't get me wrong, the parts I replaced made a difference but I'm still looking to improve especially when it's riding time in traffic.

Cheers,

Mike
 

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Discussion Starter #20
It's sorted! I managed to get out for a ride to one of my regular haunts yesterday, the distance of which is a proper test of my arthritic hand. About half way through the ride, my hand develops a pain across the back, where the tendons are, and by the time I've gone two thirds of the way I am in so much agony that I can't pull the clutch in. As soon as I pulled away yesterday I could tell that the clutch was lighter, and it sure made the bike more enjoyable to ride! I did the whole ride and did not suffer any pain at all.

If anyone wishes to have a go at it themselves (and you do this at your own risk) take off the clutch cover to expose the clutch and you will see the five springs; unscrew the allen screw holding each spring in place (do it one at a time to keep the clutch together) take out the screw, the cup under the screw and the spring. You will see that the spring cup tightens down against a pillar and this is where the new washer needs to go, to relieve spring tension. 1.5 mm is the thickest that can safely be added due to clearance issues. next, wipe off the spring and fix it in a vice until it becomes coil bound (in my case I left them compressed overnight) then making sure the spring is clean, insert it and the new washer and spring cup, and tighten the allen screw fully, then move onto the next spring.

Obviously, after doing this there is less spring pressure on the plates, so there is a chance of clutch slip, but as I don't ride hard, that is not an issue to me.

Thanks for the replies.
 
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