Sticky clutch plates

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Osiris

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I've been addressing my clutch issues since I've got the bike. It would die while in gear with clutch lever pulled. It looked as though the fluid had never been changed. I rebuilt master and slave cylinders. I also replaced stock clutch line with SS . New long pushrod and new bearing. The clutch looks to be fully Disengaging at this point. I did notice the plates were sticking together when I squeeze the lever. Is this normal? When I went for a test ride yesterday shifting was not as smooth as it should be. It does not die while in gear at idle and lever pulled. It just feels like plates are sticking together so it won't shift smoothly. Everything was within specs when I put back together. At this point I am ready to order a new clutch kit with all new plates. Any other thoughts on what might be going on?2018-01-02 11.23.17.jpg

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May or may not have anything to do with it but what type,weight motor oil are you using?
 
What levers ya got on there, some aftermarket levers are a problem. There's a thread about that on here somewhere.
 
Just a little more input. When I had the bike on the center stand and pulled the clutch lever in then engaged 1st gear the rear tire moved slightly. I released the lever and tire was fully engaged (rolling). I pulled clutch lever in again , while in gear and the tire kept moving and was very hard to stop rolling( as if it were still in gear). Once the tire was stopped with lever in, the tire stayed disengaged (not rolling). Thanks for any input guys.
 
There is normally very little clearance between the plates when the clutch is disengaged.

If the rear wheel is on the ground the output shaft can't turn and with the motor running the input is being turned by the motor which will cause the plates separate.

However if the rear wheel is off the ground and as the clutch runs in oil this will cause drag between the plates which can turn the wheel.
This effect will be more noticeable when the motor is cold and the lube more viscous but reduces as the motor heats up.

It may be that you still have some air trapped in the line.
Try tying back the clutch lever and leave it overnight which will often get rid of that last bit of air.

I know not why this works (suspect it may be due to the garage fairies) but I could be wrong and I'm sure others will give a full explanation if I'm wrong.
 
Another possibility is wear on the baskets. They can cause notching in the aluminum guides which can lead to poor operation. Examples attached. One shows heavy notching and the other a more normal wear pattern.

I would check for air in the line though as was previously mentioned. Angle the master cylinder a little so the lever is facing a little down and away. This should help let any bubble at the bolt connection out. Then the other area to catch any air is the bleed screw. It's going to be a very small amount of air.
 

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One other thing to try might be to "back" bleed from the slave UP to the master.
I have to do this from time to time on my 02 EXC 400 for the front brake when it sits for a long time.
I use a syringe/hose over the bleeder at the slave.
Can get messy so have some help IF you try it.
 
...and another thing...

When the metal of the plates is stamped out this gives rise to a 'smooth' and a 'sharp' edge to the plates.

I would check that a) they all are in the same direction and b) that the 'smooth' edges are facing out of the basket.

Also check that the gear lever pivot and ball joints are free or if they have excess wear. Either condition won't help with the gear change.
 
I think your steel disk in the clutch pack might need a cleaning if nothing is keeping the clutch from disengaging properly. Every once in a while I'll scuff my steels up, and it's like a new clutch again. Fiber disk in spec. of course. The fibers last a long time. Since I went DD clutch, my plates stick a little when the bike is cold. But are fine when warmed up.
 
I think your steel disk in the clutch pack might need a cleaning if nothing is keeping the clutch from disengaging properly. Every once in a while I'll scuff my steels up, and it's like a new clutch again. Fiber disk in spec. of course. The fibers last a long time. Since I went DD clutch, my plates stick a little when the bike is cold. But are fine when warmed up.
How long would you say?
 
Thanks for all the replies guys. I will have to try clutch lever pulled over night. I did make sure all the plates were facing same direction. I also gave the steel plates a scuff prior to install. (works great on my dirtbike) My basket was a bit worn which i lightly filed down any sharp edges. I do have another basket on the way, and I will give an update after its installed and tested.
Again thanks for all the input.
 
I agree w/''93Max,' the reverse-bleed is very useful in removing all air that may be trapped in the lines, whether for front or rear brake, or the clutch hydraulic system.

I have a brand-new Mityvac I haven't even bothered to use, I just reverse-bleed, and it's as-good as it's going to get.

Many members like the overnight tie-back of the lever approach, but if you do a good job of the reverse-bleed, it's not necessary.

During a proper reverse-bleed, you will see much bubbling coming from the very small hole of the master cyl floor, the one closest to the banjo bolt, as you purge the fluid/air from the line. As you continue to force fluid upwards, the bubbling volume decreases from many big bubbles, to small, 'fizzy' bubbles. As the fluid moving-upwards from your syringe expels all the air, the fizzy bubbles will be replaced by a solid column of the fluid emerging in a little 'geyser' from the small front master cyl hole. Should you close the bleeder valve and squeeze the brake lever, that's also what you get. At this point, I usually find that after I rapidly 'fan' the lever a few times, it quickly develops resistance , and you're done.

As others have said, with the wheel off the ground, the disengagement of the clutch will still allow the viscous oil around the clutch to spin the wheel through the drivetrain. Sean's pic of the slotted friction disc clutch basket wear pattern is seen on high-mileage, or thoroughly-used bikes. A bucks-down rider could sand down those bumps to get a little more use out of the basket. As you would expect, the clutch wouldn't allow a full release of the friction discs, if the discs are hung-up in the clutch basket wear pattern.

One other thing to try might be to "back" bleed from the slave UP to the master.
I have to do this from time to time on my 02 EXC 400 for the front brake when it sits for a long time.
I use a syringe/hose over the bleeder at the slave.
Can get messy so have some help IF you try it.
 

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