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Hi, I’m a bit new here and I tried searching all of your clutch issues and I couldn’t quite find my issues... so if I missed one with my exact problem, I apologize in advance. I have a 1998 Ducati ST2 944 that I’ve owned for about 4 years now. I replaced my slave cylinder last year. This year I decided to replace my clutch with a Barnett. I took it all apart and cleaned everything thoroughly. Thread locked the screws when I reinstalled the basket. The basket was grooved but not enough to make me replace it. I installed the new clutch and tightened the nut to 130lbs With a torque wrench. Put the springs in and tightened them gently but snug. Bled the slave and everything seems to engage. Test run showed differently. It shifts into first hard, shift down hard. When I engage the clutch handle I don’t think it engages fully. In first the bike still wants to go a bit. Won’t shift into neutral without a fight. If I turn it off, goes into neutral easily. I tried bleeding the slave again, seemed better but only for a brief moment. The bike still goes like a sob, and the clutch does not slip, but I know for a fact the lever isn’t engaging all the way. I’d love it if someone might have an idea on what’s wrong? Thanks again in advance.
 

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If everything worked before you swapped out the clutch plates then I'd measure the stack height and compare it to what you had with the old plates. Also, the bolts holding the clutch springs should be torqued to 5-7 nm.
 

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Discussion Starter #4 (Edited)
Every vid I watched with techs working on these Types of clutches showed them using an Allen wrench to tighten these springs. They are tight. I know that for a fact. Are you telling me that the clutch isn’t engaging fully because they are too tight? Because my guess is by tightening them any further I would risk damaging my posts or Possible strip them. I don’t have a torque wrench small enough to measure 7nm which I’m guessing would be around 5lbs of torque? The clutch I bought is for this bike, so I guess I’m not sure why the stack would be any larger or smaller for that matter?
 

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It's not the buttons. He was just giving you an FYI. It's probably the stack height. Do you have an aftermarket slave cylinder?
 

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Discussion Starter #8 (Edited)
It's not the buttons. He was just giving you an FYI. It's probably the stack height. Do you have an aftermarket slave cylinder?
So when I unpackaged this clutch kit I did notice there was a really thick Drive plate included. There wasn’t a plate like that on the only clutch stack, instead there were two separate drive plates at the bottom of the stack. There was also a 3 Ring damper spring In the new clutch kit that seats in the middle. There isn’t one in the old clutch at all. I wonder if that’s what’s doing it?
 

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Yes. This thing.
So when I unpackaged this clutch kit I did notice there was a really thick backing plate included. There wasn’t a plate like that on the only clutch stack. I wonder if that’s what’s doing it?
Possibly, but being aftermarket they likely achieve the same result but in a different way, you can reuse your old steels if they're not all blued up but before you start swapping anything you need to measure the old stack and then disassemble the clutch and measure your new one, if your new clutch pack is too high swap out a thinner steel from your old pack to make it about 0.5mm higher than your old pack (to account for wear of the fibres) and reassemble.

If your pack height is correct then bleed your clutch well and also make sure your lever isn't adjusted in too far as doing that will limit the throw of the clutch causing similar symptoms.

I never bother torquing the spring buttons down, i just do them up with a tee handle allen key, the torque is so light anyway i just bottom the bolt and snug it, the tension of the spring stops it coming loose and i always use copper grease on all those threads
 

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Discussion Starter #11 (Edited)
Possibly, but being aftermarket they likely achieve the same result but in a different way, you can reuse your old steels if they're not all blued up but before you start swapping anything you need to measure the old stack and then disassemble the clutch and measure your new one, if your new clutch pack is too high swap out a thinner steel from your old pack to make it about 0.5mm higher than your old pack (to account for wear of the fibres) and reassemble.

If your pack height is correct then bleed your clutch well and also make sure your lever isn't adjusted in too far as doing that will limit the throw of the clutch causing similar symptoms.

I never bother torquing the spring buttons down, i just do them up with a tee handle allen key, the torque is so light anyway i just bottom the bolt and snug it, the tension of the spring stops it coming loose and i always use copper grease on all those threads
I was editing that last comment I made and then added another with pics. Maybe this will make more sense. I’m decent with a wrench but I don’t usually work on bikes. So Please forgive my lack of technical sense at times, but yes. I’m sure I’ll need to compare the stacks. I’m really wondering about that damper spring piece? Like I said, it’s not included in the old kit.
 

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Given that you have an aftermarket slave, the amount of travel distance of the clutch rod may be different (probably less) than the OEM. If your new clutch stack is a bit too tall, combined with a little shorter throw from the slave, the clutch won't fully disengage. This can lead to hard shifting and difficulty in finding neutral. Having air in the lines can also result in less throw distance of the clutch rod. So, measure the stack height like Loony888 described, ensure there's no air in the line...and...you should be all set to ride!
 

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I was editing that last comment I made and then added another with pics. Maybe this will make more sense. I’m decent with a wrench but I don’t usually work on bikes. So Please forgive my lack of technical sense at times, but yes. I’m sure I’ll need to compare the stacks. I’m really wondering about that damper spring piece? Like I said, it’s not included in the old kit.
The damper spring in the Barnett kit looks different to all the others, in a genuine pack there's a slightly concave steel plate which is the genuine damper plate, you won't spot it unless you're looking for it, which you need to do because if you do decide to swap a steel to shim your stack height you definitely don't want to be adding that one....
 

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There is a measurement called “stack height “ Look it up for your model. It is the thickness of all of the clutch plates in a stack. Why is this important ? Because your slave cylinder has very little travel. It cannot lift your pressure plate very far. There has to be clearance between the pressure plate and clutch pack when you pull on the lever in order for the plates to release. Your new stack of plates is too thick for your slave cylinder to lift far enough to let the clutch slip. Sometimes you need to use some of your old metal plates to reduce the height of the whole stack. If you make the stack too short the pressure plate does not have enough travel to clamp the plates together, and the clutch will slip. There is a minimum and maximum stack height. You must swap plates around until you are between the two dimensions.
 

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Discussion Starter #15
Thanks guys. I appreciate the feedback. I should have just joined this forum 4 years ago. Still, I have to add, this was my first bike clutch install. I wish it was this easy to throw a clutch in my Subaru. 😑
 

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If you have something like a luggage scale you can improvise a torque wrench.
As per the attachment, know the torque nm required, attach the scale to the Allen key and use the formulae in the attached in metric and imperial.
Simple torque.png
 

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If you are referring to my post about torque, then see your post #4.
You wrote that you did not have a small torque wrench.
You don't just tighten them up, you torque them.
My way is for when people do not have a low range torque wrench, but can afford some digital luggage scales from the $2 shop.
Things are torqued to levels for good reasons.
Not having a go, just answering your post.
 

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as has been said, if it was ok before with the replacement slave and old pack then it's not the slave.

the following is something i typed out a while ago. because yours was ok before the pack went in it shouldn't be any of this, but sometimes just disturbing it all brings things out. or you just did something wrong.

if neutral is hard to find with the engine running, but easy with the engine off then it is clutch drag. possible reasons for that, possibly in combination:

1/ worn lever pivot bolt.
2/ lever worn at pivot bolt hole.
3/ pushrod between lever and master piston worn.
4/ hydraulic system needs bleeding.
5/ cross engine pushrod is worn.
6/ hub centre wearing against large washer allowing hub to float.

the barnett pack looks different, but if it is assembled correctly then it's functionally the same. new pack shouldn't have any warped steel plates.

stack height i don't see as a big issue, unless it is wrong either way by more than 2mm or so. should be 38.5mm ish with a new pack. i doubt it is an issue for you.

look at the spring caps when you pull the lever in. if the spring caps move in and out, then look at the hub centre for wear. that's very common on higher km bikes. you can add another washer to take up the wear or replace the hub.
 

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Not to detract from the previous posts: The tiniest air bubble in the clutch line/master/slave cylinders will also cause the symptoms you describe. Use a clear tube to catch the overflow, and watch to see if you get that tiny bubble.
 
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