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rkover1
11-14-2005, 08:07 PM
Greetings all,

I have a '93 SS900 with 35,000 miles. A local dealer just replaced the (original) clutch, but I am having trouble getting it to shift into neutral at stops. When I pull in the lever, it feels like the clutch is dragging and not completely disengaging. If I shut off the engine, then no problem. The adjuster at the lever is screwed all the way in. I took it back to the dealer, who offered to bleed the system, which helped some but not much.

I've been told that possibilities include the slave cylinder and the push rod. I don't know what the spec is on the rod, but don't have anything to measure it anyway.

I'm concerned that I have a brand new clutch and it's already beyond the range of adjustment.

Anyone out there had a similar situation?

doc
'93 900SS "Phaedrus"
'85 RZ350 "Buzz"

Mat
11-14-2005, 08:22 PM
Well, I am sure that I am wrong but if this were any other
bike....I say..."warped pressure plates" (AKA, the metal ones).
But, since the problem wasn't there to start with (or was it?)
then clutch springs out of adjustment (not balanced) and
lastly...limp hydraulics....there must be a bubble in there somewhere.
Well, Lets see.

Torben
11-14-2005, 09:30 PM
Check the alignment of the clutch plates first to make sure it's installed correctly and there's nothing impairing the separation of the plates.
Next, when the system was bled, was it done at the master or the slave? The master is the best place to bleed air bubbles.
If you have max throw on the clutch lever, and pump it, does the resistance increase or remain constant?

RockStar
11-14-2005, 11:00 PM
K.I.S.S. first: When I rebuilt my 748's clutch this summer I had a similar issue at first. I had initially just screwed the pressure plate in just slightly too far. Check a manual for the working range. You'll probably need a set of calipers for this.

If neutral is the only shifting issue I'd decline to think it was the push rod.

To be completely thorough it ought to be pulled out completely, center hub nut and everything and then repacked. I'm a nerd...so I did it a few times.

If you need a clutch tool, or calipers let me know.

yousef.

flyingducman
11-15-2005, 12:27 AM
Anyone out there had a similar situation?

doc
'93 900SS "Phaedrus"
'85 RZ350 "Buzz"
Yes...identical, and very recent with a new STM 48-tooth clutch-kit.

It turned-out to be a combination of two things.

First, the plate-stack was too high and needed to be adjusted. There's usually a number of drive-plates with the kit of differing thicknesses for the purpose of getting the stack-height correct. Sounds like you'll need to remove one and/or replace one with a thinner plate. I too had an extremely difficult time getting it into neutral when the bike was running, and shifting-down was especially hard (mainly 2nd/1st gears). Problems vaporized when the stack-height was corrected.

Then the clutch lever-pull went soft shortly thereafter and it once again became difficult to get into neutral when running, and down-shifting became tough again. It was remedied with a simple bleeding of the system as air must have entered the system at the time of the install.

It appears in both instances that the pressure-plate did not fully disengage from the friction and drive-plates. This must have caused the engine and/or transmission to sense this and the difficulties mentioned where the end-result.

Eastside Moto Sports was very accomodating in getting the issues rectified immediately, once they surfaced.

I now have the most amazing clutch of the three that have been on my bike!

Hopefully this helps, and you find a simple-solution to your troubles.

rkover1
11-15-2005, 08:57 PM
That was kind of my feeling: that the pressure plate wasn't moving far enough to get some slack to the plates. I had already considered removing a plate to test this. Hopefully, I'll get to try this over the weekend and get my clutch back.

If not, I may be posting again.

Thanks,

doc
'93 900SS "Phaedrus"
'85 RZ350 "Buzz"

RockStar
11-15-2005, 10:01 PM
[QUOTE=rkover1]That was kind of my feeling: that the pressure plate wasn't moving far enough to get some slack to the plates. I had already considered removing a plate to test this. QUOTE]

Maybe the 900 clutches pack differently but I wouldn't 'remove' a plate to test the clearance of the pressure plate. I've only done one model of bike which is hardly an opinion but I would think that all the toothed plates are there for a reason. IMHO. (if i'm incorrect I'd love to know so if someone differs please share your knowledge.)

y.

flyingducman
11-15-2005, 11:58 PM
I had already considered removing a plate to test this.All of the work done on my clutch was done by a Ducati-certified mechanic. You said the clutch was installed by a dealer, I'd take it back to them and have them 'tune' it, if the stack-height is the actual cause of your problem.

flyingducman
11-16-2005, 12:04 AM
I've only done one model of bike which is hardly an opinion but I would think that all the toothed plates are there for a reason. IMHO. (if i'm incorrect I'd love to know so if someone differs please share your knowledge.)

y.
This link will take you to a page on STM's website that shows the contents of one of their clutch-packs. Note the the steel 'guided' (drive) discs come in two thicknesses. This allows the stack-height to be played with a bit to get it perfect.

STM (http://www.stm.to.it/en/moto/pagina.asp?Id=86&SF=Pacchi%20dischi&F=Accessori%20per%20frizioni)

And I wouldn't just remove a disc either to 'test' it. I would look for expert assistance in the form of a Ducati-certified mechanic, or one hell-of-a-knowledgable-Ducatisti.

Here's another link to an article on proper stack-height. Note the reference to difficulty finding neutral just below some of the stack-height examples.

Stack-Height (http://www.ducati.net/faq.cfm?id=47)

RockStar
11-16-2005, 11:59 AM
And I wouldn't just remove a disc either to 'test' it. I would look for expert assistance in the form of a Ducati-certified mechanic, or one hell-of-a-knowledgable-Ducatisti.

Good article, thanks for sharing.

In the talk of 'removing' a plate I took it literally. I had forgotten that the Barnett and Haynes instructions do reference plate thickness in the build. After reading the article, I'd say mine's a little 'soft'. But after playing with spring tension, triple checking the pressure plate distance when disengaged, and riding for the last 4 months I feel safe with my handy-work (haven't missed a gear yet, lol).

Though when I have the bike retuned I'm not too proud to have my mechanic check the clutch :happy57:

Great topic, thanks rkover1!

y.

rkover1
11-17-2005, 10:01 PM
Wow. Thanks for the great article. I'll be headed to the garage this weekend with my calipers and a better idea of what to ask my friendly dealer for. I'm crossing my fingers that this will be the cure I'm looking for.

doc
'93 900SS "Phaedrus"
'85 RZ350 "Buzz"