I had noticed before winter and the last couple of early winter rides that my clutch started playing up a bit.
A couple of times it remained disengaged after releasing the lever so not sure if the master was sticking or the slave. Second pull and was normally right and onyl happened a handful of times. I suspected the slave on that occasion (but haven't touched) as the master is a reasonably new and buy all accounts good condition remote res version with the large pivot pin like early SBK's and I think later injected SS's and ST's.
Last couple of times I rode before pulling front end apart I noticed it was a bit notchier when engaging first but didn't really think anything of it. When front was apart I pulled the clutch cover removed all the plates and blew out all the dust. Looked at plates but didn't touch and put back in in same order ( apart from maybe turning back to front the odd friction and steel plate but not the outside thick one).
Now bike is back on road the clutch is worse. No leaks but harder to get into first and creeps a little. Sometimes stalls at lights when you miss neutral from second and get first at low revs. Used to find neutral fine but hard now overshooting from both first and second. Also hard to change down on the move sometimes. Up shifts still fine and no jumping out of gear or anythign else strange.
Initially thought it time to look at new plates but then realised that worn plates would create slip which is not happening.
So my suspects would appear to be either the master or the slave but neither appear to leak. Also given the slave will surely be much older than the master I thinking that. Would it likely be crud in there somewhere stopping the slave from extending to correct depth. This is my next path of investigation but any ideas to help speed the diagnosis.
Also on the subject given the differences between new and old clutches what the best option as far as getting updated/new clutch plates and say springs for the older clutches.
Clutch issues
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eliatt
Hi,
lt looks like master cylinder partial stroke, and/or control plate failure. to eliminate, try to adjust stroke free play by screwing in the adjusting screw on lever. also notice if lever travels all the way outwards when released.
Possible reasons to failure may be: dirt, piston O ring weare, spring failure (rare), or cylinder bore weare ( ovalization). measure the control plate springs as well. should be 40mm. long, check inner core of control plate - tends to breake.
good luck!
lt looks like master cylinder partial stroke, and/or control plate failure. to eliminate, try to adjust stroke free play by screwing in the adjusting screw on lever. also notice if lever travels all the way outwards when released.
Possible reasons to failure may be: dirt, piston O ring weare, spring failure (rare), or cylinder bore weare ( ovalization). measure the control plate springs as well. should be 40mm. long, check inner core of control plate - tends to breake.
good luck!
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fester
Thanks eliatt.eliatt wrote:Hi,
lt looks like master cylinder partial stroke, and/or control plate failure. to eliminate, try to adjust stroke free play by screwing in the adjusting screw on lever. also notice if lever travels all the way outwards when released.
Possible reasons to failure may be: dirt, piston O ring weare, spring failure (rare), or cylinder bore weare ( ovalization). measure the control plate springs as well. should be 40mm. long, check inner core of control plate - tends to breake.
good luck!
Have adjusted master screw fully in and no difference. Lever however seems to work fine and does fully release. Control/pressure plate is also fine as I pulled the clutch apart just before getting back on the road to inspect and clean all the dust out properly. The springs were also intact but I did not measure.
Someone on 906 forum suggested warped plates which also makes a bit of sense so unfortunately it's looking like time for a full recondition of the clutch assembly. I've also got a CNC pattern for milling the cover to what I'm led to believe was the factory pattern used on race bikes of the period, I suspect the 750 F1. So might go the whole hog and do the lot.
Bike has 48,000klms and the last owner only did a couple of hundred in 2 years with no maintenence and owner before that seems used to use it for track days and BEARS/Ducati club meets so maybe clutch is just tired.
Definately didn't see any leaks though and it was playing up before I pulled it apart by the way.
Next question then becomes what are the best plates to buy to get the right combination and what are the right springs. No-one seems to have come up with a replacement for the pressure plate either (although mines not broken yet it looks to have been repaired before so would be nicve to get a new one).
Can the basket be replaced.
And yes don't forget we are talking dry clutch here not wet. Wet plates would be different but maybe springs would be the same.
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fester
Thought I should have addressed that and that someone would ask. Yes it should be fine unless there has been a hidden air bubble for the last thousand or so kilometers.jcslocum wrote:Has the system been properly bled?? It's difficult to properly bleed the system so it takes time and patience.
I pulled the original coffin style master out about 6 months ago and replaced with a remote reservior version and the system was fully bled then and was working fine. I also give it a bit of a rebleed the other day before heading out on a run.
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eliatt
Hi,
I bought the original clutch kit from http://mdinaitalia.co.uk/ (it`s about GBP 88 + shipping) did`nt need springs, but was told it`s about GBP 3-4 each. also check http://www.ferracci.com/store/cart.php? ... missing .
I bought the original clutch kit from http://mdinaitalia.co.uk/ (it`s about GBP 88 + shipping) did`nt need springs, but was told it`s about GBP 3-4 each. also check http://www.ferracci.com/store/cart.php? ... missing .
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jcslocum
- paso grand pooh-bah
- Posts: 1714
- Joined: Mon Jul 19, 2004 12:00 am
- model: 750 Paso
- year: 1988
- Location: Eastern Shore, MD
- Contact:
So, if the system has been properly bled, then you have a piston "travel" issue. There are 2 buttons inside of the clutch, 1 on the slave and 1 on the clutch plate plus the bearing in the piston. All of these items can wear and reduce in height causing the piston to have LESS throw than it was designed for.
You need to inspect these parts for wear to determine if this is the cause for the clutch not fully disengaging.
Clutch Plate Button:
http://www.box.net/shared/yz5173fq6m
I'd start with thoroughly bleeding again to see if you can get a bubble out. The bubble that gets trapped in the banjo up top at the master can really be hard to remove. The mechanincs of the system are really simple so the root cause should be easy to find.
You need to inspect these parts for wear to determine if this is the cause for the clutch not fully disengaging.
Clutch Plate Button:
http://www.box.net/shared/yz5173fq6m
I'd start with thoroughly bleeding again to see if you can get a bubble out. The bubble that gets trapped in the banjo up top at the master can really be hard to remove. The mechanincs of the system are really simple so the root cause should be easy to find.
Piero According to the dealer the Monster 600 plates are the same as the paso. i fitted them without any problems and the clutch works as it should no prob's. but now you say that m600 has oil cooled clutch i am not so sure but it's what the dealer sold me.ducapiero wrote:Dave i know that the monser 600 have an oil clutch
the plates are the same???
amny thanks
Piero
Dave.
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fester
Will have to pull all apart this weekend and see if I can find the culprit.
I remember finding a thread (and can't now) with a lot of discussion about the slave button and maybe sourcing or getting some made but don't recall if anyone ever got the original measurements of a new unworn one, does anyone know.
I don't care about the shaft etc but only the thickness of the button itself for both slave and plate. I might look at getting the boss's father to machine a couple up for me.
I did look at both buttons casually when I pulled it apart and they looked OK but now is the time obviously to look carefully and get measurements if available.
What does the needle roller bearing do that sits underneath the ball bearing race inside the slave piston.
Also seeing as these things do wear and have age on them has anyone looked at getting the slave cylinder sleeved and rebuilt from there. I know when we were playing around with some of the old English cars that local firms were rebuilding worn master cylinders by stainless steel sleeving and fitting new stainless pistons.
I remember finding a thread (and can't now) with a lot of discussion about the slave button and maybe sourcing or getting some made but don't recall if anyone ever got the original measurements of a new unworn one, does anyone know.
I don't care about the shaft etc but only the thickness of the button itself for both slave and plate. I might look at getting the boss's father to machine a couple up for me.
I did look at both buttons casually when I pulled it apart and they looked OK but now is the time obviously to look carefully and get measurements if available.
What does the needle roller bearing do that sits underneath the ball bearing race inside the slave piston.
Also seeing as these things do wear and have age on them has anyone looked at getting the slave cylinder sleeved and rebuilt from there. I know when we were playing around with some of the old English cars that local firms were rebuilding worn master cylinders by stainless steel sleeving and fitting new stainless pistons.
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fester
Thnaks paso750 that's the thread. I have a photo that I'll try and add to the thread when I work out how but I'll add a link here as the is the most recent clutch topic and it might be handy to refresh everyone.
I dug this out of an old performance bike magazine I was reading that was around from the early 90's here in Australia.
The bike I think is a Pantah of some description that appears to have been built for racing by Peter Smith of Epicycle. Peter was involved in the factory superbike race team here in the early 90's when they started with the 851/888 and he and the team were very successful in developing the bikes on a limited budget.
What's of interest to me however is (a) it looks like the bike was converted to cable clutch operation and more importantly (b) it looks like he manufactured a new pressure plate design that also looks like it is aluminium in construction. That would be somethign handy to get into production again me thinks. Thoughts?????
http://members.optusnet.com.au/~gavnkym/gallery.html
My other thought on the slave piston/bearing design was could a new piston be made that has say a tapered needle roller bearing seated in the bottom to take the rotational and thrust loads with a longer bodied pin coming up to the correct height. Could this then be sealed with one of those oil dust seals commonly used in the back of front hubs on cars and in the front wheel of our bikes (my 17" version at least). It seems their design is to retain oil/grease on one side and prevent dust/dirt ingress from the other. Lust not sure how effective they would be with the fine abrasive dust or heat from the clutch?????
I dug this out of an old performance bike magazine I was reading that was around from the early 90's here in Australia.
The bike I think is a Pantah of some description that appears to have been built for racing by Peter Smith of Epicycle. Peter was involved in the factory superbike race team here in the early 90's when they started with the 851/888 and he and the team were very successful in developing the bikes on a limited budget.
What's of interest to me however is (a) it looks like the bike was converted to cable clutch operation and more importantly (b) it looks like he manufactured a new pressure plate design that also looks like it is aluminium in construction. That would be somethign handy to get into production again me thinks. Thoughts?????
http://members.optusnet.com.au/~gavnkym/gallery.html
My other thought on the slave piston/bearing design was could a new piston be made that has say a tapered needle roller bearing seated in the bottom to take the rotational and thrust loads with a longer bodied pin coming up to the correct height. Could this then be sealed with one of those oil dust seals commonly used in the back of front hubs on cars and in the front wheel of our bikes (my 17" version at least). It seems their design is to retain oil/grease on one side and prevent dust/dirt ingress from the other. Lust not sure how effective they would be with the fine abrasive dust or heat from the clutch?????