1100 clutch problem

[ggemelos]

I had my 2009 1100 at the dealer yesterday to have them install the DP tail kit.  While it was there they also lifted the tank to install the DP tank bag strap.  All of this seemed pretty simple and took very little time.  When I picked up the bike, the clutch was feeling a bit odd.  When I released the clutch, there seemed to be a bit of a delay before the gears engaged.  At first it was somewhat subtle and I did not think anything of it.  That is until it got to the point where the gears just stopped engaging completely.  This happened on the highway on my way home.  I pulled in the clutch, changed gears, and nothing happened when I released the clutch.  It was like I was still holding in the lever.  After pulling off the road I inspected the bike and there was a very loud squeaking sound coming from around the slave cylinder whenever I released the clutch lever.  

The bike was towed back to the dealer for them to take a look.  This all happened yesterday and today I heard from the dealer and they said that they bleed the clutch and it seems fine now.  They want to hold on to it for another day to see if more air gets into the lines.  They never said how air would get in to the lines in the first place.  The bike only has 1300 miles on it and was running perfectly the day before.  I am not too happy with what appears to be a fix of the symptoms without any attempt to determine the cause.  They claim that this sometimes happens with ducatis.  Has anyone else heard or experienced this?  Any ideas what it could be?  

The bike is pretty much stock with no modifications to the clutch hydraulic system.

[ducpainter]

Air in the lines would not cause the problem you described.

It would cause the opposite. You wouldn't be able to shift easily.

Have you or anyone else changed or messed with the clutch lever?

[ggemelos]

I also was unable to figure out why air in the line would do this.   I tried to asked the tech how it would cause this type of behavior and got a lot of circular talk.  As for the levers, I have not touched them other than to bring them in a bit using the adjustment screw.

[ggemelos]

I just got off with the tech again.  He apologized and said that when he last spoke with me he was not aware of all he symptoms the bike was having.  The shop has decided to send the case details to Ducati NA and see what they suggest.  I am hoping they just swap out the whole clutch.  I guess this is not a problem that has shown up a lot here.  I'll post any future updates.  Thanks for the reply ducpainter.

[ggemelos]

Here is the latest update.  The shop thinks that sediment in the hydraulic lines caused the piston to jam.  They flushed the lines and replaced the slave cylinder.  They say all appears to be good and that I can pick up my bike.  It sounds reasonable, much better than air in the lines, but how does sediment get into the hydraulic lines of a new bike?  The shop manager also apologized for the initial report of air in the lines.  He said the shop tech just saw that they flushed the lines and assumed that air in the lines was the issue.

[ducpainter]

<snip> As for the levers, I have not touched them other than to bring them in a bit using the adjustment screw.

That is your problem. It is not a reach adjustment. Adjustable levers are for that.

You need to maintain about 1.5mm of free play in the lever. If you don't, you block the return hole in the master and as the fluid heats up it actuates the clutch.

Readjust the bleed back screw and the problem will go away.

[ggemelos]

That is your problem. It is not a reach adjustment. Adjustable levers are for that.

You need to maintain about 1.5mm of free play in the lever. If you don't, you block the return hole in the master and as the fluid heats up it actuates the clutch.

Readjust the bleed back screw and the problem will go away.

Are we talking about the same screw?  The one I adjusted was the screw on the front outside of the lever.  It is not actually part of the hydraulic system.  All it does is adjust at what point the lever rests against the hydraulic system.  You adjust it my pulling the lever forward so that it is not touching the hydraulic system and then turn the screw.     

[Slide Panda]

Yeah - he's talking about *that* screw. If you turn it it too far - it blocks the fluid return to the reservoir and could cause problems exactly as you described.

[ggemelos]

OK.  I had it turned so that the lever was closer to the handlebar.  I did not realize that it would have any impact on the flow of the hydraulic fluid.  How should it be set?  Ducpainter said to keep 1.5mm of free play.  How do you measure free play?

[ggemelos]

The users manual calls this screw the span adjuster.  So maybe we are talking about a different screw.  If so, sorry for the confusion.  My mechanical vocabulary leaves much to be desired. 

From the manual:
The lever (1) disengages the clutch. The span adjuster (2)
serves to alter the distance of the lever from the handlebar.
Lever distance is adjusted by 10 clicks of the knob (2).
Turn the knob clockwise to move the lever away from
twistgrip, or anti-clockwise to move it closer.
When the clutch lever (1) is operated, drive from the
engine to the gearbox and the rear wheel is disengaged.
Correct use of the clutch lever is very important in all
riding situations, especially when moving off.

[Slide Panda]

Ah - the item you have circled in black is the lever adjustment. Turning that will not have the impact that DP or I described - it's primary function is to adjust how far the lever rests from the handlebar. BUT it does have the secondary effect/ side effect of changing the volume of fluid moved by the master when you pull the lever. The longer the lever throw, the more fluid. Now, on a bike that's in proper running order, it'll make no noticeable  difference.

That particular adjustment screw is harder to access, and you would need tools to change it's position - not just fingers to turn a knob.

The problem you described sounded like something was preventing the fluid from leaving the clutch slave, or preventing the clutch slave piston from retracting into the slave body. 9 times out of 10 when someone has this problem, it due to the fact they adjusted the screw that DP was referencing, and turned it in past the point, so now it occludes the return port. The effect of that is a slave piston that is slow to, or will not retract.

[ggemelos]

Thanks for the information and clarification.  The shop guys suggested that the fluid was being blocked by some sediment.  Since I never adjusted the bleed back screw, it seems like a reasonable explanation that is consistent with what DP and yuu are saying would cause the symptoms I experienced.   

[KRJ]

  I have had this problem on My '07 MTS several times, and yes just bleeding the system fixes it for a while. I'm thinking that when the clutch wears, the slave piston is moved deeper in the cylinder, displacing more fluid to the reservoir and for some reason it doesn't take much to keep the piston from releasing the clutch. the first time this happened I was riding for about five miles and clutch lever free play went away in a couple pulls then clutch started to slip, luckily I was close to home and arrived before total disengagement. If I keep the fluid level at the bottom mark of the reservoir, I have had no problem. The fact that the clutch plates are seated in may help in not generating excess fluid level also. I will do some more research on this,You wouldn't think such a small change in fluid height would cause this. And yes I checked master cyl. lever free play, piston action and travel, slave cyl. condition, pushrod and clutchpack condition, etc., everything looks good, not a trace of "sediment" or anything.   I'm leaning towards something with the clutch master cylinder not allowing fluid to return, thus bleeding pressure from slave cyl. nothing can be seen externally, have to tear it apart.   

[ggemelos]

I am not sure that clutch wear played a big role in what happened to my bike.  I only have 1300 miles on the bike.  I cannot imagine that the clutch wear would be significant enough with so few miles on the bike. 

[ducpainter]

I forgot the 1100 has radial masters....

sorry.