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Discussion Starter · #1 ·
Hello all,
Let me preface this all by saying i've searched for an answer on previous threads, to no avail so if this has been solved before; i truly am sorry!

I just recently bought my bike with 9000 miles. Everything has been working really good with 0 problems, up until about 3 nights ago. I was out for a ride when i noticed that my clutch, instead of engaging far away from the lever had now moved to almost completely AT the lever. :confused: That being said, the amount of force that i have to put on the lever in order to get to that spot, is extremely hard. I literally have to hulk it, when 4 days ago i was 2 finger clutching. I have adjustable levers, but I've had them for a while so i do no think they are the cause of this. I've also come to notice that when the bike is cool, at highway temp and speed of about 165F and 70 mph, the clutch is relatively simpler to use and squeeze. When i get stuck in traffic and its running at about 205F the lever is damn near impossible to squeeze. I opened up the reservoir last night and noticed that the fluid is at the LOW line. I have yet to swap out the fluid, but could this possibly be the cause of this? I have a Yoyodyne slave cylinder so I kind of ruled that out, although i don't know when it was installed on the bike. I called a local ducati racing performance shop and they couldn't give me a straight answer or idea, they just told me to bring it and let them strip it down for the tune of $200 just to look at it. If i could avoid this costly check up, i would love too as i'm on a tight budget right now. :think: Any advice or ideas would be greatly appreciated!

Damian
 

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Mr Leakered
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Too large of a stack height usually causes a hulking pull, but only because the springs have bottomed out. That wouldn't apply here because you haven't messed with the pack.

Heat usually causes a mushy clutch because the fluid is old or the throw out bearing in the PP is worn and causes the push rod to spin in the slave and vaporized the fluid.

In correct adjustment (typically with new levers) can cause some slippage of the clutch and locking of the front brake. The lack of slippage on your issue is a bit weird.

You may want to start off by seeing if you get a squirt of fluid in both resevoirs with the initial movement of either lever. If not, then you need to back out the adjustment pins a bit. Otherwise, a fluid flush, including a bleed at the master cylinders might not be a bad idea.

Have a good one.
 

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You should definitely start by bleeding the clutch with new fluid to see if any air bubbles or moisture are trapped in the system. Use dot 3 or 4 or 5.1. Check for sources of air/moisture ingress like for example loose bleeder at the slave or banjo at the reservoir. That being said, is the aftermarket slave a "wide bore piston" type, designed to make the lever action lighter? If so, then perhaps the plunger actuator screw in the lever was not turned in a smidge so the rod will be pushed enough to disengage the plates as one loses rod travel with wider bore piston, if the plunger acutator screw isn't turned in a bit. If you have the stock lever, the material placed over the plunger screw's grub/set screw, found on the underside of the lever body, would have been dug out to get at the grub screw (that's really easy to strip using a teeny allen key) to back it out to be able to then turn the plunger actuator screw in a smidge to get better rod thrust/plate separation/smoother shifting. :)
 

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Discussion Starter · #4 ·
Hello,

Thanks for the quick reply. I have a question, when you say to check for a squirt of fluid in both reservoirs, do i have to suck out the fluid in the reservoir first to see it; or how would i go about doing this? :confused: Sorry man, i feel like a noob. Last night i pulled off the clutch lever and i did notice that the pin itself had gone in about 1 mm or so, so i brought it back out to what the OEM lever spec was (i left the setting on my caliper by dumb luck lol) when i originally removed it and it seemed to do nothing to alleviate the problem. I'm going to leave work early and bleed out the whole system, should i remove the slave cylinder to see if there's any gunk building up there or just a basic clutch fluid flush?

Thanks alot,
Damian
 

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Discussion Starter · #5 ·
Hey Stryder,

I'm not sure if the slave is wide bore or not. When i bought the bike, it was already installed on there. How would i be able to tell? I do have the stock lever, that being said. The previous owner must of gotten into a tough time trying to remove or change the pivot pin because the pin broken. The grub screw literally does nothing for retention anymore. The pivot pin screws in or out freely, which is why last night when I removed it i added some blue permatex to the threads to help keep it from dancing around on me. I can use a 6mm transparent hose attached to the bleeder valve on the slave correct? I'm right at the low mark on the fluid so i would imagine air probably snuck in.

Thanks again,
Damian
 

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If by pivot screw you mean the plunger screw, it should not be moving freely in and out of the reservoir, it needs to be set at a certain number of threads, the optimal number to be determined for your particular slave, (check the web site for the slave maker or pull it, ie if the piston is 27+ mms wide it's a wide bore IIRC) hence a set screw for consitent lever action/shifting.

You can use another screw, don't ask me how I know, if the set/grub screw is missing, I forget the pitch size, but I was able to cut one down and thread it in there and it works very well, ie binds the plunger actuator screw so it's fixed. The plunger actuator screw needs to be set deep enough to get optimal plate separation/rod thrust, BUT, and here's the tricky part, not so deeply into the revervoir that the plunger blocks the fluid return hole, otherwise the plates will not rengage/springs/PP move the rod-slave psiton fully back all the way, so you will have to find that sweet spot. Not hard to do. Good luck. :)
 

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Mr Leakered
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You should definitely start by bleeding the clutch with new fluid to see if any air bubbles or moisture are trapped in the system. Use dot 3 or 4 or 5.1. Check for sources of air/moisture ingress like for example loose bleeder at the slave or banjo at the reservoir. That being said, is the aftermarket slave a "wide bore piston" type, designed to make the lever action lighter? If so, then perhaps the plunger actuator screw in the lever was not turned in a smidge so the rod will be pushed enough to disengage the plates as one loses rod travel with wider bore piston, if the plunger acutator screw isn't turned in a bit. If you have the stock lever, the material placed over the plunger screw's grub/set screw, found on the underside of the lever body, would have been dug out to get at the grub screw (that's really easy to strip using a teeny allen key) to back it out to be able to then turn the plunger actuator screw in a smidge to get better rod thrust/plate separation/smoother shifting. :)
I would avoid DOT 5.1. It is compatible with 3 and 4, but I think it either shrinks the seals a bit or ?? I swapped back to some racing dot 4 and my master clutch leak has gone away. I've never used DOT 5.0, but I'm starting to think the 5.1 is a bit of bad juju also.

Hello,

Thanks for the quick reply. I have a question, when you say to check for a squirt of fluid in both reservoirs, do i have to suck out the fluid in the reservoir first to see it; or how would i go about doing this? :confused: Sorry man, i feel like a noob. Last night i pulled off the clutch lever and i did notice that the pin itself had gone in about 1 mm or so, so i brought it back out to what the OEM lever spec was (i left the setting on my caliper by dumb luck lol) when i originally removed it and it seemed to do nothing to alleviate the problem. I'm going to leave work early and bleed out the whole system, should i remove the slave cylinder to see if there's any gunk building up there or just a basic clutch fluid flush?

Thanks alot,
Damian
There no need to suck out the fluid to observe the squirt. On my ST with the older remote resevoirs, it is very easy to see the squirt/distrubance in the fluid. If I move the lever fast enough, it will actually squirt out of the res. I'm assuming the ST3 coffins are similar.

Have a good one.
 

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Yes Tony, the coffin reservoirs will show the "squirt" when the covers are off.

Since it was working "normally" up to a few days ago...try a fluid replacement and bleeding. See what happens then.
 

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Discussion Starter · #9 ·
Ok, I just finished completely flushing out clutch system. One my ride home, the clutch literally dissapeared. I could not get out of gear into neutral. It would go first to second, I was essentially rev matching in order to get into gears. At a full stop, with lever pulled all the way in (as much as I could pull it), the gear was still engaged and the bike would stall out as it would continously creep forward. I would have to get to a red light, turn off the bike, put into neutral, turn bike back on when time to take off for a green light. But the weird thing I'd that when I would turn the bike back on, I would get 2 or 3 squeezes of the clutch before it just went AWOL again. In the process of bleeding out the clutch fluid, I also went ahead and turned the plunger pin in a thread or so (1 mm or so) and it made it a little easier to squeeze for about 30 seconds then instantly became hulk again. Now I have completely stripped all the lowers fairings off and am about to succumb and take the bike into the ducati performance shop. I don"t know what else to do, short of pulling out clutch pack and the slave cylinder to see what's going on in there. Any other ideas? Maybe the clutch really IS shot?? I just don't understand how a part works one day, then the day following its just gone... ?

Thanks Again,
Damian
 

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... I just don't understand how a part works one day, then the day following its just gone... ?

Thanks Again,
Damian
It sounds like your clutch is dragging, not slipping, that means it's the actuation mechanisims between lever and PP need to be tuned in or there may be a faulty component IMO. I don't think it's the clutch pac so I wouldn't start/go there at first. There may be a leak somewhere, maybe even the slave or the reservoir; the reservoir fluid return hole may be blocked, plunger too far in; the push rod may be bent; the after market slave may be the wrong model for your bike. Pull the slave and check for leaking. There should be no clutch fluid behind it. Pull the rod and roll it on a flat smooth surface to check for trueness. Bleed the system again and make sure no air is being sucked in and dial that plunger in as it's very critical to good clutch action. I was advised that as long as the bike doesn't stall when you are on it and dropping it into first, should be okay re plunger setting. Go to the Yoydyne site and make sure you have the right slave on the bike, EG, my aftermarket slave, not Yoyo, came with an extra bit of rod that some models required otherwise it wouldn't work. Good luck. :)
 

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Mr Leakered
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In the process of bleeding out the clutch fluid, I also went ahead and turned the plunger pin in a thread or so (1 mm or so) and it made it a little easier to squeeze for about 30 seconds then instantly became hulk again.
Not in, out. Out until you see squirts in the res. It sounds like your building fluid pressure and cooking it. Or, the throwout bearing is toast.

Have a good one.
 

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Discussion Starter · #12 ·
Ok, So last night I rode my bike over to my friend that has a workshop. He works on bikes on the side, his primary line of work is on yacht motors and cars. He has a 500 hp Hayabusa running 28 lbs of boost that he was professionally racing a few years ago. Back to topic, took it there last night and left it over night for him to tinker with. He just called me recently to tell me that the Clutch Slave Cylinder is shot and I need to replace it. If that's the only problem, then I feel lucky. I'm not sure if I'm going to pick up the newer style Yoyodyne's or just go with a Evo or Oberon. Any inputs? Quick question, what leads to a slave cylinder taking a crap.:confused: It's my understanding that there isn't too many things; could my pressure plate bearing taken a crap leading to this problem??

Thanks for all the great and timely mannered responses!
Damian
 

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If the slave is shot, and as it didn't have enough force on the push rod to even separate the plates, ie your clutch drag, it's unlikley the throw-out bearing is shot, especially in a wet clutch like your '05'er. "Defects in materials...(components)" happen all on their own many times, without being linked to another components. Replace the slave, and make sure you set the plunger screw correctly at the clutch lever, ie enough to separate the plates, but not enough to block the fluid return weep hole, and go from there. :)

I still don't understand why the lever pull was so hard at times. :confused:
 

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Slave piston was likely scoring the bore thus leaving a bur making the pull hard.
 

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Discussion Starter · #15 · (Edited)
Solved!

Ok, I finally got the clutch slave cylinder in yesterday late in the afternoon through mail order. I got one of the new style Yoyodyne. They seem to have a decent warranty/guarantee they seem to offer. I hope to never find out if they live up to their word haha. Anyways, it 100% was the CSC. It was a simple direct swap, slapped it on there. Flushed the system 1 good time afterwards, and hopped on the bike and took her for a test ride. WOW, what a difference. I must have bought the bike with the CSC already going bad, because what i thought was "normal" before doesn't even compare. Now i can literally feel everything through the lever and clutch lines. It's truly amazing how different the feel really is. Its very simple to 2 finger clutch. Today i did a small bleed to get rid of any build up air that might of snuck in, and she's still running strong no problems. Oh and i pulled the push rod out, and she seemed straight and true. Now my next project, time to tackle the damn spark plugs. :mad: 2 of them are supremely simple, 2 of them are almost impossible without what seems like removing a bunch of things. The right hand side is giving me problems, time to crack open the maintenance manual. Thanks for everything guys, you've been great help!!

Damian


PS - Oh i forgot to mention, during the take down of the fairings i found a sweet little surprise that i didn't even know was there. On the right hand side, right above the battery i found a Power Commander III tucked away ready to be used. Now I have even more reasons to spend more money on the bike! hahaha
 
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