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Old 24-Jul-2009, 23:32
hotchillie hotchillie is offline
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clutch issue

Help me please, my clutch seems to be broken. i cant select neutral when the bike is running, and it seems to be hard to move the lever when still as the clutch isnt releasing properley. i have bled the clutch, what else can i do.
please help me
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Old 25-Jul-2009, 00:32
TopiToo TopiToo is offline
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Hello hotchillie

Don't panic, have you checked the clutch plates and basket?
maybe they are worn and need a change/refresh.

Also check
pressure plate bearing/pushrod o rings, master cylinder o rings/pistons.

But I have no idea what bike you are talking about, so good luck.

TopiToo
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Old 28-Jul-2009, 00:23
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Gobert23 Gobert23 is offline
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Which bike/model is it that you have? (there's no mention in the post)

I've got an early 916 (Strada) and have exactly the same 'issues' and was very close to taking it into the dealer to get checked (and probably stripped back down) before I posted up for some pointers here...

Turns out that all the early bikes are like that...

Once you've selected/engaged a gear and are running, it's incredibly tricky (but not impossible) to select neutral if you'r ethen stationary.

The trick is to 'snick' (that'll be my new word for the day) it into neutral as you're rolling towards a stop, coasting that last few feet.

G
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Old 28-Jul-2009, 01:04
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DSC Member Shazaam! Shazaam! is offline
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Bleeding the Clutch Hydraulic System

If you are unable to engage neutral the most likely cause is air in the clutch hydraulic line. A trapped air bubble can compress (the fluid can't) so you won’t get a full stroke of the clutch pushrod and the clutch doesn’t fully disengage. Another common reason that the clutch won't completely disengage is that the aftermarket force-reduction slave units (and later model Ducati slave units) move the clutch pushrod less distance - a design trade-off to accomplish a reduction in clutch lever forces.

Air bubbles rise to the highest point in a hydraulic system so that's where bleed nipples belong and are usually placed. In Ducati superbikes the bleed nipple is placed at the lowest point in the system (duh) so the only way you can bleed all the air out is for the bubbles to be carried along with the fluid as you bleed, and bleed, and bleed the system. It is possible to bleed the system without using a bleed nipple at the master cylinder, but it takes a lot more work.

So, the Ducati clutch line is notoriously difficult to bleed using just the nipple at the clutch slave cylinder. Evoluzione and Yoyodyne, two aftermarket manufacturers of slave cylinders, encountered customer bleeding problem complaints so began selling a banjo fitting having a bleed nipple for use at the highest point in the hydraulic system. It works.

Here’s what it looks like:



However, you don't necessarily need one. You can try just loosening the bolt slightly and bleed with the regular banjo bolt as if it were a bleeder type. Careful though, any sprayed hydraulic fluid will damage painted surfaces.

Another reason why the clutch won't completely disengage is that any aftermarket force-reduction slave units (and later model Ducati slave units) move the clutch pushrod LESS DISTANCE - a design tradeoff to accomplish a reduction in clutch lever forces.

In other words you're pushing the clutch pushrod with a smaller hydraulic pressure applied over a larger slave piston area that gives you the same force needed to stretch the clutch springs. It just doesn't move as FAR.

The higher the force-reduction percentage (i.e. the larger the diameter of the slave cylinder), the less the clutch pushrod is moved, and the more likely that your clutch will not fully disengage.

If you have one, changing an adjustable clutch lever's engagement point (between the 4 and 1 lever positions ) has the effect of moving the slave cylinder the additional 1+ mm you need, right away.

Last edited by Shazaam! : 28-Jul-2009 at 01:15.
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