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Old 14-Apr-2006, 06:35 PM
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zhed44 zhed44 is offline
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Clutch Hydraulics - HELP! ***LINK***

I've read blueto's thread but as my symptoms and possible causes are slightly different, I'm putting up my own thread.

I replaced the clutch plates last week, however, as the clutch cover gasket was knackered I decided not to re-fit it. Big mistake, as the spring caps then fouled the inside of the clutch cover due to lack of clearance. As a result, the clutch wasn't disengaging and while having a fiddle, I squeezed the lever hard a few times, although I'm not really sure what I expected that to do! Whilst squeezing the lever, I heard a click from the master cylinder/clutch lever end of things. I then whipped off the cover and realised what had happened ie: the caps fouling the cover and I put the gasket back in.

However, I am now left with a clutch lever that will work for a while before going dead again. It might be my imagination, but the biting point sometimes seems to be in a different place.

It was particularly bad today - I was out on a ride-out with a couple of mates and spent the last 50 miles of it doing clutchless up AND downshifts. Every time we hit a set of lights in the villages, I was left stranded because, having no clutch lever effort, the bike would stall when I came to a halt.

I would then switch off, get it into neutral and start off again. The lever would be fine for a mile or 2 before the biting point got progressively closer and closer to the bar again, leading to miles of clutchless shifting followed by stalling at the first set of traffic lights I encountered

We stoppped at a garage and I bought some DOT4. I topped up the resevoir as the fluid was a bit low and I also noticed that the fluid was brown and horrible. This top up helped for a while, but soon enough, it was up to its old tricks again and I had to limp home, clutchless shifting and stalling all the way.

I'll obviously try renewing the fluid and bleeding the system, but I'm thinking I may have popped a seal somewhere by pumping the lever (thereby overpressurising the hydraulic system) when the cover was fouling the caps.

What do you lot reckon?

Thanks

[Edited on 14-4-2006 by zhed44]
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Old 14-Apr-2006, 08:28 PM
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Fordie Fordie is offline
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Zhed, when you pulled the clutch apart did you check the pushrod , ive had one break before and that will give intermitent problem. The pushrod can stick if the bearing on the pressure plate is siezed then it spins the pushrod and knacker the slave cylinder seals although the brake fluid does turn dark soon after replacing it turning brown does'nt sound to healthy ,any signs of leakage at the slave. It may be a replacement slave cylinder needed 4D
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Old 14-Apr-2006, 08:31 PM
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rockhopper rockhopper is offline
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Yep, push rod would be my first guess.
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Old 14-Apr-2006, 09:12 PM
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Nigel C Nigel C is offline
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Don't worry about the colour of the brake fluid .

qoute: "they all do that sir " :quote
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Old 14-Apr-2006, 09:38 PM
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zhed44 zhed44 is offline
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Quote:
Originally posted by Fordie
Zhed, when you pulled the clutch apart did you check the pushrod , ive had one break before and that will give intermitent problem. The pushrod can stick if the bearing on the pressure plate is siezed then it spins the pushrod and knacker the slave cylinder seals although the brake fluid does turn dark soon after replacing it turning brown does'nt sound to healthy ,any signs of leakage at the slave. It may be a replacement slave cylinder needed 4D

thanks for the advice - much appreciated

when it started doing it last week after i'd replaced the clutch plates i took all the plates out and put them back in again just to make sure that i had done it properly. one thing i did do was i only used one plain plate in the base of the basket, because this was how the clutch pack that came out was made up. however, this cannot be the cause of the problem because it was already happening after i had used 2 plain plates the first time i installed the pack. however, the pushrod looked fine - and as i was also thinking i'd possibly bent the pushrod, i did have a look, but in all honesty i couldn't tell whether or not is was bent.

i had the fairing off earlier and there is no sign of leakage anywhere in the system.

i'm really puzzled as to why the lever is ok for a while and then loses effort. the bike was ok for all of last week after nelly talked me through some fixes on the phone including slackening off and then retightening the slave cylinder bolts in order to possibly release the pushrod. the bike was fine after that when pottering around london, but it's only today after speeds of *ahem*mph and some reasonably spirited riding that it's started playing up again and if anything is now worse than it was.

BTW: what is the function of the recessed screw in the clutch lever mechanism, the end of which operates the button/rod that goes into the master cylinder? can it/should it be adjusted? i can't find any mention of it in the haynes manual.

i mentioned earlier that happened when i was forcing the lever when the caps were fouling the cover that i heard a "click" - well the click came from the area of that screw/button interface. could something have failed in that little mechanism?

one last thing - when i took the cap off the resevoir today, the diaphragm was hanging down like a little condom inside the resevoir. i didn't think anything of it, but when reading the haynes when i got back, i noticed that this diagphragm is supposed to be compressed. is this significant?

sorry about the essay length post

[Edited on 14-4-2006 by zhed44]

[Edited on 14-4-2006 by zhed44]
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Old 14-Apr-2006, 09:49 PM
m1keyp m1keyp is offline
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Push rod?

Where are you two pairs of eyes my be better
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Old 14-Apr-2006, 10:00 PM
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zhed44 zhed44 is offline
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Quote:
Originally posted by m1keyp
Push rod?

Where are you two pairs of eyes my be better

i'm in london - the irony is that i wasn't too far from you earlier today as part of our ride headed up into cambs.

you would have easily recognised me, i was the one on the black ducati stamping the living daylights out of the gear lever

[Edited on 14-4-2006 by zhed44]
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Old 14-Apr-2006, 10:17 PM
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Rushjob Rushjob is offline
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Quote:
one last thing - when i took the cap off the resevoir today, the diaphragm was hanging down like a little condom inside the resevoir. i didn't think anything of it, but when reading the haynes when i got back, i noticed that this diagphragm is supposed to be compressed. is this significant?
Yes, it could be.
If the diaphragm is extended it means that there is very little if any fluid left in the reservoir.
Also check that the clutch lever is not fouling on the indicator switch assembly.
If this has rotated around the handlebar or the lever angle has been altered, the clutch lever can catch and not fully release, causing problems similar to that which you describe sometimes giving a click when you operate it......( Found this out going through Nice in the rush hour... ! )
I'd be tempted to chceck the lever clearance, fully bleed the system & try again.
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Old 14-Apr-2006, 11:23 PM
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zhed44 zhed44 is offline
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Quote:
Originally posted by Rushjob
Quote:
one last thing - when i took the cap off the resevoir today, the diaphragm was hanging down like a little condom inside the resevoir. i didn't think anything of it, but when reading the haynes when i got back, i noticed that this diagphragm is supposed to be compressed. is this significant?
Yes, it could be.
If the diaphragm is extended it means that there is very little if any fluid left in the reservoir.

as i said in one of my other posts, the fluid level was very low. so much so that it would have been possible and indeed likely that with the acceleration and lean angle i was using that the hole at the bottom of the reservoir would have been exposed.

what i find really puzzling is that there seemed to be a cycle today that went like this:
normal operation for a few miles - biting point starts getting closer to bar - lever pulled back to bar eventually doesn't release clutch - bike stalls when at standtill due to clutch drag - switch off - put in neutral - wait 2 minutes - normal operation again......and so on.

i took the lid off the resevoir before and pumped the lever a few times and just one tiny air bubble emerged, so it's not full of air at the master cylinder end.

i'm also at a loss to know:

a) if there are no leaks, where has the fluid gone as the fluid level was fine last week?

b) if there is air in the system, apart from the possibility of the hole being exposed and air getting sucked in, then how did it get there as there are no leaks and i haven't taken any of the hydraulics apart?

c) if there is air in the system, i would have thought that i would have a spongy lever, end of story and that i would be able to get more effort by pumping the lever. however, what i actually have is a lever that works fine for a while but the biting point gets closer and closer to the bar until it disappears altogether.

one other thing that i have remembered, is that today, when i lost the lever effort on the move, i was sometimes, but only occasionally able to get it back by wobbling the clutch lever hinge vertically up and down in the hinge or by flicking the clutch like i was wheelying the bike. i would then have a clutch for a few gearchanges, before it went awol again.

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Old 15-Apr-2006, 02:10 AM
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DSC Member Shazaam! Shazaam! is offline
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http://www.ducatisportingclub.com/xm...1975#pid209275
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