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Discussion Starter #1
so after about 15 minutes of city driving my clutch just slips and wont grip...The bike revs and i go nowhere, with the bike off and in first gear i can push the bike forward without the clutch lever pulled in.
Once i let it cool down its ridable again and the clutch feels tight. Will bleeding the clutch slave cylinder help?
Is there any trick to that or is it just open the nipple at the slave cylinder and pull lever until all air bubbles are out and i see solid stream of fluid...?
 

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What condition are your friction plates in? How deep does your clutch pack measure?

Im thinking bleeding the clutch will help release the plates, they should clamp themselves together & drive with the spring pressure?

Might just been worn out! :)
 

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Discussion Starter #3
What condition are your friction plates in? How deep does your clutch pack measure?

Im thinking bleeding the clutch will help release the plates, they should clamp themselves together & drive with the spring pressure?

Might just been worn out! :)
I'm not sure as I haven't pulled the clutch cover yet. Ill do that tonight. I ask about bleeding as I had to slightly loosen the slave cyl fluid hose to get the side cover off enough to re-seal it cuz it was leaking oil after previous owner did a starter replacement and didn't seal it.

What fluid should I use for slave cyl resi?
 

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The return port in the master cylinder is either plugged or covered by a misadjusted MC piston. It isn't allowing the heat-expanded clutch fluid to return back to the reservoir.

Properly adjusted, there should be a 5-10% dead-band of the full lever movement before there is pull resistance felt at the lever. This freeplay is necessary to prevent covering the MC reservoir return port.
 

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Sounds like the master cyl. piston screw on the lever was screwed in too far. If this is done, the MC piston is in too far, blocking the bleed hole in the master. Sort of like riding your clutch lever all the time. And as the stuff (fluid) heats up, it expands and puts pressure into the slave which makes your clutch slip.

If you don't know how to adj. this piston screw, bring it to someone who does.

Same thing applies to the brake side. If it is mis-adjusted, as the fluid heats, the brakes start getting applied harder +harder...

EDIT: (thx Shazaam, just noticed you replied while I got side-tracked here at work!)
 

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Discussion Starter #6 (Edited)
The return port in the master cylinder is either plugged or covered by a misadjusted MC piston. It isn't allowing the heat-expanded clutch fluid to return back to the reservoir.

Properly adjusted, there should be a 5-10% dead-band of the full lever movement before there is pull resistance felt at the lever. This freeplay is necessary to prevent covering the MC reservoir return port.
Ok thanks, Is there a free place that covers how to install and properly adjust a clutch slave cyl? All of the online resources for a FSM are costly.

found this
http://www.ducatisuite.com/clutch.html.

I'm still concerned that my the washer, sleeve and 3 rubber grommets that slid on the plunger on the clutch slave cylinder wasn't installed in the proper order.
 

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Discussion Starter #7
Sounds like the master cyl. piston screw on the lever was screwed in too far. If this is done, the MC piston is in too far, blocking the bleed hole in the master. Sort of like riding your clutch lever all the time. And as the stuff (fluid) heats up, it expands and puts pressure into the slave which makes your clutch slip.

If you don't know how to adj. this piston screw, bring it to someone who does.

Same thing applies to the brake side. If it is mis-adjusted, as the fluid heats, the brakes start getting applied harder +harder...

EDIT: (thx Shazaam, just noticed you replied while I got side-tracked here at work!)
Ok thanks, this might be it. I have a auto-retracting kickstand and the guy who test rode the bike before i got it forgot about the auto kickstand function and tipped the bike over trying to stand it up and broke the clutch lever in half which may have tweaked it enough to throw the adjusting screw out of spec.

You guys are great
thanks again
 

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This appears to eventually happen to old SS models. I went through it myself this spring. Changed slave first, no fix, rebled lines, no fix.

You were exactly right, the pressure in the lines does not release and expanding fluid in the lines causes the clutch to be partially released.

While the unit can be adjusted, it is fixed at the factory with mastic. But the mastic can be removed to gain adjustment. I also did this. Winding counter clockwise (I think from memory) will move the bite in point closer to the grip and give you more travel before clutch pressure is applied and begins releasing the clutch.

In the end I came to the conclusion, it was only a bandaid. That a sticky piston caused by a piece of seal or (?) was blocking the return port and line pressure was not being released. The fluid went dark quickly.

A new Brembo master cylinder fixed the problem permanently.

I had to paint the gold brembo black to match.

Bob

Sounds like the master cyl. piston screw on the lever was screwed in too far. If this is done, the MC piston is in too far, blocking the bleed hole in the master. Sort of like riding your clutch lever all the time. And as the stuff (fluid) heats up, it expands and puts pressure into the slave which makes your clutch slip.

If you don't know how to adj. this piston screw, bring it to someone who does.

Same thing applies to the brake side. If it is mis-adjusted, as the fluid heats, the brakes start getting applied harder +harder...

EDIT: (thx Shazaam, just noticed you replied while I got side-tracked here at work!)
 
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