Clutch Drag…

[Leamreject]

I’ve recently stripped my 2006 S4RS clutch down to lightly reface the clutch plates as they were glazed and gave an annoying squeal when pulling off.

It’s a dry slipper clutch so quiet a simple and quick job. However, now that it’s all back together I appear to have clutch drag, pulling the lever doesn’t disengage the clutch enough which prevents me selecting first whilst stationary unless I kill the engine. Symptoms are very similar to having air in the system, so although I haven’t tampered with the hydraulics as a precaution I’ve bleed the clutch but to no avail.

Anyone experienced the same or can throw some suggestions my way?

Thanks
Rob

[Dukedesmo]

Sounds like You're not getting enough plate separation, so possibly the slave cylinder is not fully actuating or too thick a clutch pack?

[Luddite]

Do you have an aftermarket slave (eg Oberon) and did you remove it? Some slaves have a small spacer between the piston and the pushrod. Is it possible this could have dropped out?

[Leamreject]

Originally Posted by Luddite

Do you have an aftermarket slave (eg Oberon) and did you remove it? Some slaves have a small spacer between the piston and the pushrod. Is it possible this could have dropped out?

Yes, it does and ironically the wife (whilst barking instructions at me) pulled the clutch lever in while it was all apart. I will check that next, thank you

[350TSS]

Did the plates go back in the same order? In some clutches there is a dished plate that is supposed to be fitted in a certain position in the pack and is there to aid the separation of the plates when the lever is pulled. You will have to check the manual for the position of that dished plate if there is one in your assembly.

[Leamreject]

Originally Posted by 350TSS

Did the plates go back in the same order? In some clutches there is a dished plate that is supposed to be fitted in a certain position in the pack and is there to aid the separation of the plates when the lever is pulled. You will have to check the manual for the position of that dished plate if there is one in your assembly.

Yes, I was quite careful in ensuring they went back as they came out

[Leamreject]

Originally Posted by 350TSS

Did the plates go back in the same order? In some clutches there is a dished plate that is supposed to be fitted in a certain position in the pack and is there to aid the separation of the plates when the lever is pulled. You will have to check the manual for the position of that dished plate if there is one in your assembly.

Yes, I was quite careful in ensuring they went back as they came out

[Dukedesmo]

I doubt the dished plate orientation would make any difference.

For what it's worth, I run both my Ducatis without any dished plates and have no clutch issues of any kind.

[Leamreject]

Originally Posted by Luddite

Do you have an aftermarket slave (eg Oberon) and did you remove it? Some slaves have a small spacer between the piston and the pushrod. Is it possible this could have dropped out?

Would anyone have a clutch slave spacer knocking around that needs to be used? I’ve searched eBay and can’t seem to locate one to purchase.

Thanks
Rob

[Mr Gazza]

You shouldn't need the spacer on your 2006 model.
The spacer is to compensate for the shorter early push rods. Your pushrod could also have an "anti-rotation" pin which would certainly confirm it is the later longer type.
It wouldn't work at all with a short pushrod if the spacer was not present.

I'm curious as to what you mean by "lightly re-face the plates" and how you went about that.

[Leamreject]

Originally Posted by Mr Gazza

You shouldn't need the spacer on your 2006 model.
The spacer is to compensate for the shorter early push rods. Your pushrod could also have an "anti-rotation" pin which would certainly confirm it is the later longer type.
It wouldn't work at all with a short pushrod if the spacer was not present.

I'm curious as to what you mean by "lightly re-face the plates" and how you went about that.

It’s a little odd as I dismantled and rebuilt it in the same order, and with a medium dry emery rubbed each face a few times on a flat surface, nothing significant as you would if doing brakes. There isn’t much on them to start with so it was only very light.

It has a non standard billet clutch slave, but I didn’t remove it and when I pulled the rod out nothing obvious came out with it but I’m now getting clutch drag because the clutch won’t disengage fully even on full lever adjustment. If I’d have taken too much off I would have the opposite being clutch slip. It really appears as if it needs more movement.

I’m going to dismantle it again and see if anything obvious jumps out. One thing I did notice is that the plates had little tabs on them and I didn’t spot how they were positioned when I dismantled it. I refitted them in random positions.

[Nasher]

Did you re-check the stack height after refacing the plates?

The Stack height is critical and just a tiny amount of each side of all the friction plates will have probably reduced it too much.

[Leamreject]

Originally Posted by Nasher

Did you re-check the stack height after refacing the plates?

The Stack height is critical and just a tiny amount of each side of all the friction plates will have probably reduced it too much.

I didn’t, but will get the vernier out when I dismantle it again. Do you know what the tolerances should be?

[slob]

http://ukmonster.co.uk/monster/showpost.php?p=584116
post #2

[Leamreject]

Originally Posted by slob

http://ukmonster.co.uk/monster/showpost.php?p=584116
post #2

Super… thanks Slob