Hydraulic Clutch Fluid Issue

[Ron1000]

Looks worse than it is…i cleaned it too

[Luddite]

Originally Posted by Ron1000

Is it possible for the engine vibration to gently rotate the clutch shaft?

Ducati vibration can unscrew all sorts of fasteners, so I wouldn't rule it out!

Originally Posted by Ron1000

One last thing when you say ‘started to unscrew’ do you mean that keyed part isn’t freely rotating? Does it have threads it’s supposed to tighten into? If so i would imagine mines would start to rotate again.

I haven't had an Oberon apart, but I'm assuming that it screws together.

This type of slave has an anti-rotation pin to stop the pushrod damaging the cylinder. Since the clutch rotates anticlockwise (when viewed from the clutch side), if it wasn't free at the clutch end, then it would impart a turning force to the slave, which might be enough to twist the back plate. Pull the slave off again, (don't lose the pin!), and see if you can turn the pushrod easily. I wouldn't have thought this would be an issue with wet clutches though.

If you look closely at your picture, there appear to be two punch marks; one on the outer casing and one on the back plate. Should these be aligned, I wonder?



You could always email Oberon explaining what happened and see what they say. admin@oberon-performance.co.uk

Originally Posted by slob

sprocket is very worn on the side of the teeth, something’s out of alignment. almost like the boss has been fitted on the wrong side of the sprocket, except that side would wear on a 696 with the sprocket fitted for 796/1100.

I wonder if that's just the chain cutting through old lube, Rob, rather than wear of the actual sprocket.

[Ron1000]

Pushrod defo rotates easily, i tried that earlier.

What does the anti-rotation pin look like? Is it the main pin that goes through the pushrod?

Front does look worn from the side but it’s fine it’s probably just a bad photo, the front sprocket, rear sprocket and chain all got fitted at the same time and have a 8k miles on them. So I’m not overly worried.

[Mr Gazza]

Originally Posted by Ron1000

All that chewing on the inner un-anodised part seems to be on the side facing away from the chain. Almost as if the chain would have to be looped over the slave to cut it in that way.
That inner part of the slave must have rotated towards the chain to have contacted it, so I would investigate that the clutch pusrod is free to rotate. (with the engine stopped!) as it could be turning the slave inner portion, as Vince suggested.
If it is not possible to turn the pushrod then it's in need of a new bearing in the pressure plate.. This is assuming that the pushrod has a small pin through it at rightangles about 10-15mm from the slave end? I don't see it in the pictures, perhaps it has snapped off flush with the surface of the rod?
Strange though that the inner part appears to be in the correct orientation with the body after the truama?

[Ron1000]

That picture is slightly misleading as i had rotated it back to it’s correct position and had test fitted it then took it back off for the photo.

Pushrod rotates easily by hand and the right angle pin is present.

Diagram of slave for info if anybody needs it:


So I’ll take it back off tomorrow and see if that inner un-painted machined part screws in or not or is otherwise damged in anyway. I’ll also check the pushrod rotates easily and that the pin is present (it is) and that the two indents line up. If all of that checks out I’ll just need to run it and get confidence in it again.

[Luddite]

Originally Posted by Ron1000

What does the anti-rotation pin look like? Is it the main pin that goes through the pushrod?

Yes, it's the pin shown here in your photo.



I've just done the obvious and pulled my slave and there are indeed two punch marks:



As you can see, mine appears to be slightly further round (clockwise) than yours.

[Luddite]

I see from the diagram you found that the punch marks are shown and are aligned, so they obviously are a datum, but presumably alignment is not critical.

[Ron1000]

Thank you very much for doing that Luddite. And thanks to everyone else for the info.

I definitely know how it all works now. Weird that it moved in the first place tho.

[Ron1000]

More weirdness.

open source screen capture

I can’t get the two indents to meet now. Which is weird as that inner machined part was easy to rotate yesterday, now it’s solid. I’ve tried a reasonable amount of force and it won’t budge.

Which essentially means the push rod isn’t at the ‘correct’ rotation. Does that matter? Seems like it does to me!

Can’t decide wether to run it as is or just order a new (non oberon) clutch slave. And use one of my other bikes in the mean time.

[Mr Gazza]

I think there is something quite wrong with slave now, they shouldn't turn like that.
I also think that there could very well be something wrong with the pusrod, or rather that the thrust bearing in the pressure plate is siezed or very stiff.

I wouldn't be putting it back like that if it were mine.
First call would be to Oberon to see if they have come accross this before and to see if they can throw any light on it. As the inner has turned in the body it could well have damaged a seal or scored the mating surfaces, which would presumably be an interferance fit. Swarf or grit could be the reason why you can't turn it now?

I would also be tempted to start the motor in neutral and see if I could stop the pushrod from turning, maybe gently with some pliers padded with masking tape to try and not damage the pushrod. I shouldn't really be suggesting that on a public forum as it could be potentially dangerous if you happened to catch the anti-rotation pin and the rod actually was seized in the bearing, so please procceed with caution at your own risk!

I have heard some good stories about Oberon, so a meek approach for advice might possibly get a good response.

P.S. Don't take the p!ss, I typed this entire post witout the aid of a spellchequecer

[Ron1000]

Ok so evo parked up until i speak to Oberon and buy and new clutch slave any (non-Oberon) alternatives you guys recommend?

The push rod turns by hand easily i done that last night.

[Mr Gazza]

I'd still be tempted to try and hold the pushrod while the engine is running, just to prove that there's no tight spots or if it grabs at any point.. With the above caveats of course. It might be that it only grabs and turns when the clutch lever is in and the pressure is on?

I've used an Oberon myself for many thousands of miles and so I would reccommend one, but if they came back with an unhelpful response from an enquiry about an issue like yours I would buy a FactoryRacing one.

Good luck..

[Ron1000]

The plot thickens.

I’ve taken the clutch slave off again to check the push rod and this is what if find. Mind it’s not been started or ran from putting it back together earlier. (Pushrod rotates easily on both directions by hand with engine off and in neutral and with the bike running and in neutral. Can’t test it in gear.







screenshot windows 7

So the inner part that tight just fell out on removal. The inner part is actually threaded into the outer part. When i screw them back in together the indents are in the wrong position as you can see. Something catastrophic has happened I’m being to suspect a thrust bearing issue. I might have only done temporarily then freed itself off again. Dunno dunno dunno.

[Luddite]

Don't write off the cylinder just yet!

I think the problem may be that it's still connected and the piston will have eased out a few millimetres making it difficult for you to screw the cap on.

Ideally, you should remove the slave completely but, if you don't want the extra hassle of bleeding, try this in situ first.

Try to push the piston back into the body as far as possible, (making sure your reservoir isn't going to overflow when you push the piston back in), and then try to refit the back plate.

If that fails, I'd definitely get in touch with Oberon.

Good luck!

[Luddite]

Originally Posted by Ron1000

Which essentially means the push rod isn’t at the ‘correct’ rotation. Does that matter? Seems like it does to me!

PS I don't think it matters at what position the pushrod sits as, without the slave, it's free to rotate at both ends. As long as the anti-rotation pin is engaged, it'll be ok.