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Discussion Starter #1
Yesterday while I was bleeding my brakes (on my GT) and changing the brake fluid, I had a lot left over. It seemed reasonable to do not only the front but also the rear. Then I screwed up and decided to change the clutch fluid. I grabbed up the bleed vac, sucked put the reservoir, refilled the reservoir, then hooked up to the bleed nipple on the slave. All seemed to go well but now the clutch doesn't seem to work right in that it never completely disengages the gearbox. I pumped it, bled it at the slave, bled it at the master, hooked it back to the vac, cussed at it many time and did all this over several times. It still doesn't work. It is as if the slave doesn't move through its full travel or as if the clutch plates are stuck together. I have had this problem before and the shop claimed it was the clutch plates sticking, they fixed it but here it is again 500 miles later. (They fixed by unsticking it but didn't replace anything.)

How do I fix this?

I believe I have bled the system correctly as the lever feels firm and good but ...

How do I unstick the clutch plates? I have no idea how much of the motor needs to come apart to fix this. I don't mind tearing into it but need some advice on what to tear open as I don't want to do exploratory surgery on my favorite bike. (If it were my SS, there would be piles of parts everywhere by now but it isn't my whoreish SS, it is my GT and I love her.) I do have the ability to fix this (I think anyway) but have no guide whatsoever.
 

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If its a dry clutch, just remove the cover, , springs, pressure plate to gain access to the clutch basket and plates. If Wet, same thing just have to drain oil or lean bike over.
 

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Bleeding the clutch is forever a pain. Takes forever to pump up by hand, if you can even get it done in one session. One time when installing a new slave, three of us took turns squeezing the lever and bleeding the slave for over an hour and it still would not pump up. (mind out of the gutter guys, this is pure mechanical love) That was until a buddy of mine showed us a trick when a friends 749 clutch quit working in the middle of a ride hundreds of miels from home. He simply squeezed the lever to the grip, and let it snap back. Squeez, slip you finders off the lever and let it snap back. Do this a few times in a row, then see if it will pump up. As soon as we rememberd this trick the clutch pumped right up and worked great!! Sounds too easy right? I think what it does is get any last air bubbles out of the master to flow into the fluid reservoir. Try it before you start taking things apart.
 

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Remember, the pumps are at the highest point, so you need to bleed the system AT THE PUMP, be it brakes or clutch!

It's really quite simple, I don't understand why people have problems with this simple fact.

Tom
 

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Discussion Starter #5
It is a GT so it is a wet clutch and my experience at dismantling Ducati's involve dry clutch bikes, thus my wariness.

I will try the snap action thingy, thanks.

I have bled it at the master the best I could as there is no bleed there. I pumped it and loosened the banjo, got a squirt and shut it quickly. I did this first, last and somewhere in between. No luck yet.

Any other suggestions would be appreciated also. Right now the lever is compressed and I am trying that trick. We'll see.
 

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Remember, the pumps are at the highest point, so you need to bleed the system AT THE PUMP, be it brakes or clutch!

It's really quite simple, I don't understand why people have problems with this simple fact.

Tom
I don't think people are having problems with this fact. We all know those pesky bubbles are supposed to rise to the top. All I can tell you is I've bled lots of brake and clutch systems, and for some reason my own experience with the Ducati clutch, as well as countless other cries all over the internet have shared the same frustration. It's a pain. As 3-D mentioned, there is no bleed valve at the clutch master. Plus, I usually get air from the brake calipers and master, so would argue that bubbles could accumulate at some "low" points for whatever reason (kinks, casting, etc.), and all valves should be bled.

The other thing I hear a lot is to tie the lever back to the grip with a zip tie and let it sit all night long, supposedly giving the bubbles a chance to make it to the reservoir.
 

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i have a big syringe (can find them at paint stores/hardware stores) with a length of clear silicone tube that fits tightly on the bleeders. i use it to suck a vacuum on the system at the slave bleed fitting and pour fluid into the reservoir at the top. i know the bubbles should rise up to the reservoirs (eventually, in theory) but they seem to get sucked out with the fluid faster/more efficiently than by waiting for them to rise up to the top. so far i've replaced several slaves and a couple master reservoirs with this technique and it's always worked well.

for brakes, get yourself a set of speed bleeders - do a search on the forum, i think they've been posted before. these are replacement nipples for the slave bleeds that have an ingenious little ball/spring valve in them and let you pump/bleed the brakes without sucking air back into the calipers. all you do is open them 1/4 turn, put on the bleed hose to your waste bottle and add new fluid to the reservoirs as you pump out the old stuff. they're cheap (less than $20 if i remember correctly) and work like a charm. makes bleeding brakes a one-person job (without cussing) :)
 

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Discussion Starter #8
I have the older, brake only version of this - http://www.griotsgarage.com/product/car+maintenance/oil+changes/multi+fluid+extractor.do?search=basic&keyword=bleeder&sortby=newArrivals&page=1

With that, I sucked all the fluid from the bleed nipple on the slave while making sure to keep the reservoir full. Afterward, among many other attempts, I used it to "power bleed" the system, several times - no luck.

I am now thinking of taking the system off the bike, attaching the clutch lever an m/c to an old bar. hanging the thing upside down form the garage ceiling, doing a voodoo chant and then bleeding it. Anything has got to be better than this crap.
 

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I think the complicating factor with bleeding the clutch is the fact that you are working against another part that moves a long ways. When bleeding brakes, the MC is basically pushing against an immovable object.

When bleeding the Clutch, if there is air in the lines, when you pump up the brake, the slave moves. When you release the pressure on the bleed valve, the slave moves back. So, fluid can move more back and forth in the system than it can on a brake system, instead of always just moving away from the MC.

Vacuum bleeding should prevent this from being a problem, but that's the issue that Dietrich's "snap action" thing is trying to address.

You might have more success bleeding the line with the Slave detached from the engine case. This would make it much more like bleeding brakes. It would also allow you angle the slave into the best position for getting bubbles out.

I understand ST2Lemans point, but that frequently does not remove air far downstream of the pump. The point is not that you need to bleed at the pump, but that you need to bleed at BOTH locations to be certain you are getting everything out.
 

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Discussion Starter #10
I think .... you are getting everything out.
MS, do you think I even want to hear from you right now? They are your old brake lines that started me down this road this after all.:p

Actually it is Ducati I want to kick square in the ass for including a master cylinder without a bleed. Whoever the pasta counter is who spec'd the suspension, valve guides and clutch m/c should have to ride a rusty, old Huffy with flat tires for the rest of their life.

Now, let me ask- If I made a cover for the M/C reservoir that had a port in it to hook to a vacuum source of some type, could I bleed it from the top?

However, I have removed the M/C and slave. While they were off the bike, I bled it in every position I could think of. One pump of the M/C would then bottom the slave out. Once installed, the problem remained and made me wonder.

In the past, it did something similar and the shop claimed the clutch plates were stuck together. Would the plates in a wet clutch actually stick together? I understand how this could happen in a dry clutch if it gets wet or contaminated but isn't a wet clutch bathed in engine oil? The oil is pretty fresh, only a few hundred miles but probably 60 to 90 days old.
 

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I swapped my slave a couple weeks ago and must have gotten lucky as I had it bled in about 1/2 hour and only one reservoir refill of fluid. I had not bled anything in years so no skill involved, must have been dumb luck:D
 

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MS, do you think I even want to hear from you right now? They are your old brake lines that started me down this road this after all.:p
I plead complete innocence when it comes to your clutch. That one's all on you. ;)

Now, let me ask- If I made a cover for the M/C reservoir that had a port in it to hook to a vacuum source of some type, could I bleed it from the top?
Yes, but I'm not sure you don't have a bigger problem.

In the past, it did something similar and the shop claimed the clutch plates were stuck together. Would the plates in a wet clutch actually stick together? I understand how this could happen in a dry clutch if it gets wet or contaminated but isn't a wet clutch bathed in engine oil? The oil is pretty fresh, only a few hundred miles but probably 60 to 90 days old.
Yes, that can happen, but normally only if sitting for a very long time or if an oil is used which is incompatible with wet clutches. I think it's more likely you have a hydraulic problem, and, with your description of what you've already tried, it would most likely be MC or Slave. Since it is not unusual for the clutch slaves on these bikes to have problems, that's my first guess. Unfortunately, I don't know of any way to be certain other than testing with a known good cylinder.

If you've put in some weird oil, or an oil additive, then my first guess switches to the clutch plates.
 

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Discussion Starter #13
I plead complete innocence when it comes to your clutch. That one's all on you. ;)
I thought we had a deal and you were going to be my scapegoat - Don't leave me hanging bro!

Yes, but I'm not sure you don't have a bigger problem.
My worry also...

Yes, that can happen, but normally only if sitting for a very long time or if an oil is used which is incompatible with wet clutches....
I use Golden Spectro 20W/50 and either K&N or Ducati filters so I don't believe that is it, however....
It sat, broken down, at the Ducati dealer's warehouse in Charleston SC for 8 or 9 months. It was during one of the brief visits I had with my bike that I noticed this problem. Now its back.
How do you fix the sticking clutch if this is the case?
The oil was changed in either late May or early June and has about 500 miles on it. While I don't mind changing it, I would like to figure out if I am opening up the side case/clutch housing before I potentially waste that much oil.
 

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major is correct - the stock slaves fail often. they kinda suck too... so you'll be doing yourself a favor to pick up an aftermarket slave: they are to be had on ebay reasonably and besides the bling factor, most of them use bigger pistons and will give you a significantly lighter clutch pull.

easy-peasy swap out and you'll be happy you did it.

if that ISN'T the problem (i think it is) then when you do find the gremlin you'll still have a sexy bit o' bling that makes riding in traffic much nicer :)
 

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Discussion Starter #15
A new slave sounds great, HOWEVER the clutch isn't moving enough to disengage the gearbox now, how is an aftermarket slave with larger piston and shorter travel going to do anything to make it worse. I do believe the slave is OK and it was replaced during those months in the shop so it has very little use.

I do not believe it is the clutch slave but is in the clutch plates.

Anybody got torque specs for that side case?

I think first I will take it out and ride the living crap out of it. If it breaks, then the problem will define itself - If it breaks free, then I am saved a lot of work - If nothing happens, at least I had fun.
 
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