clutch and pressure plate

I had the clutch sticking problem back in February when I bought my 2007 that has been brought up here. The sticking went away after 1500 miles, but I still couldn’t pull in the clutch and move the bike around the garage when the engine was cold without giving the bike a good push to break the plates lose; the bike has 17,000 miles on it now.

We had some rain and ice a couple of weeks so I decided to pull the clutch out and take a look at it. The inner three clutch plates were coated with thick black grease (it looked like grease anyway) and these plates were stuck to the friction plates. I needed to use a pick to carefully work the plates apart. I cleaned the plates with kerosene and put all the plates in oil for an overnight soak. The grease was preventing oil from getting to the plates.

I happened to put the pressure plate on my finger through the bearing opening and it was very much out of balance. I used a clutch alignment tool for a car, mounted and leveled in a vise to check the balance. Using stick on tire balancing weights it took ¾ ounce to balance the pressure plate. This seemed like a lot of weight for a six inch aluminum disk. I considered whether or not it was supposed to be like this or not and decided to balance the pressure plate by removing rough castings edges and some of the plate itself with a dremel tool. It took about an hour of carefully removing a little bit of material at a time to get it in balance.

Curiosity got the best of me and I pulled the clutch basket out to check it for balance. The clutch basket was essentially balanced, but I removed some material from the rough casting edges to get it balanced as much as I could.

My clutch now releases immediately regardless of engine temperature and I no longer need to put a slight preload on the shift lever to achieve very smooth shifting; much nicer.

I had a moderate amount of vibration in my foot pegs, side covers, and the trim piece on the bottom of the gas tank prior to doing this work. All of that vibration is gone and although I considered the bike to be smooth before, it is much more of what I expected when I bought the bike; happy!

I don’t know for sure if balancing the pressure plate had anything to do with eliminating the vibration or it had something to do with disassembly of the clutch. Anyway, I’m much happier with the bike now.

https://picasaweb.google.com/heise7/HeiserMcTrip/photo#5145860676757757618

As much weight as there is in the mass accumulated in a clutch it makes perfect sense that it could be a source of vibration if out of balance-the balancers are there to compensate for crank imbalance, I doubt the clutch was included in the equation, your findings make perfect sense. Makes me wanna rip Franks clutch out and have a looksee.

Thanks for reporting back. Congratulations on the "fix"! Too bad there isn't a way to find out what the black substance was and where it came from.

What a great post! Thanks for sharing, it's the first post I've read about clutch inbalance.

Great post! Mine is still sticking at 3,300 miles if the dealer won't honnor the warrenty I'll be looking to fix myself. Looks like I'll be looking at the balance also.

In all the bike forums that I have been on......I have never heard of anyone doing this...but it makes sense.

I suspect you have a lot of folks thinking about tearing into their clutch.

Thanks for clueing us in

Excellent job!

Nice writeup dude.

If you want your image to show you will have to edit it and ad [/img] to the end

photo#5145860676757757618[/img]

Clutch Picture

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Wow. You had to remove a lot of material to get that bad boy balanced. Not being able to eyeball the whole thing in that piccy, any guess as to what was the root cause of the imbalance? Is there anything on the assembly that might explain it?

https://lh3.google.com/heise7/R2nFBYXMHrI/A....JPG?imgmax=512

I'll give the pic another try....

I think I read in a post earlier in the year someone took their bike to a dealer and the dealer found the same black stuff on the clutch plates and speculated it was some type of assembly lube. In my case the stuff was flushed out the outer plates , but remained on the inner three plates, effectively blocking any oil from saturating the friction material.

One other thing, the casting finish on the heavy side of the pressure plate was rougher than the lighter side of the plate. It had a irregular and wrinkled surface. I sanded off the rough surface before I took the dremel to it.

vabrzn's picture was uploaded to his picture site at 1600x1200 resolution, with a file name of sarah apt x-mas 2007 20010.JPG, the site then resized the picture and assigned it a number. When this happened the picture lost the file extension JPG. The Forum requires that an IMG ends in a specific picture file type such as JPG or GIF. vabrzn's picture will have to remain a link until the he finds a way to get the file name to end with the extension JPG and with nothing else after it like imgmax=512.

vabrzn said:

In my case the stuff was flushed out the outer plates , but remained on the inner three plates, effectively blocking any oil from saturating the friction material.

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Thanks for the post. I could never understand why an oil bath clutch needed to have the plates "soaked" like so many say their dealers are doing. This kinda explains that.

I don't know if I would have ground those grooves in the back like you did, fearing the creation of a potentialy weak spot. I think I would have ground the back more uniformly, maintaining the original shape. But you are on the right track. Mines coming out ASAP, at least for the cleaning.

vabrzn,

Could you expound on your "balancing fixture" a bit more for thiose that may want to undertake this balance check?

You indicate that you "used a clutch alignment tool for a car, mounted and leveled in a vise to check the balance." I'm not sure what you mean there. Would leveling the tool really effect the rotational balance of the clutch that much?

I'm also assuming that you used the clutch's own bearing and just balanced like we would a wheel/tire right? How much drag do those bearings have? How hard was it to find the heavy spot? Seems like they must have turned pretty easily based on the degree of accuracy you were getting.

Thanks in advance

Took my clutch out today to see what's up regarding this thread.

06A model, 30K miles, Rotella synthetic

No black smoog

Plates were getting oil

Presure plate balance was checked using it's own center bearing and found to be off a tad. A tad is equal to one tiny wood screw that would not register on a really good electronic scale in grams, or on the oz scale to .000

Exercise basically for nothing. But I did get to see the cool diaphram spring they use on the clutch. Neat idea.

Now I need a new gasket!

S76 said:

Took my clutch out today to see what's up regarding this thread.

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Did you like the clutch action before?

Indiana Tom - I adapted to the clutch before, but was annoyed I couldn't move the bike around just by pulling the clutch in. I didn't like holding the clutch in for 10 seconds or so before putting it in first gear to prevent the , "klunk", either. Before I would pull the clutch in and would hear a rumbling sound, which went away and the bike would then go into first gear without a klunk. When I pull the clutch in now there is no rumbling sound and no klunk going into first gear without waiting for 10 seconds.

The photo below shows the first set of plates( engine side) after I did the first cleaning after removing them. You can see some of the black goop that hasn't been cleaned off. This stuff was only on the first three plates. You'll notice the friction material on these plates is black and somewhat shiny in appearence. All of the other plates are light brown and have a dull finish. I think these plates were dragging on the steel friction plates when the clutch was pulled in which would cause the klunk when putting the bike in first gear with engine running and not allow the bike to move by just pulling th clutch with the bike in gear and the engine off. In hindsight I should have replaced atleast the first two plates.



Fred W-

I didn't remove the bearing and used the clutch alignment tool becuase it would the first thing I found that fit the inside diameter of the bearing. I cleaned the engine oil out of the bearing with WD-40 to reduce resistance to movement while balancing. I balanced the plate just like balancing a tire. My plate was obviously out of balance. If I released the plate with the heavy spot on top, the plate quickly rolled until the heavy spot was on the bottom and went half way up the other side before resting to a stop; I think i had a bad casting job on the pla



S 76 - More uniform grinding would be a better way.

Have Great X-mas

Very cool find. Thanks so much for the explanation and pics.

thanks for the pics vabrzn, I think I'll visit my dealer soon and see if he's bored. He had apparently done some clutch work for someone else recently, maybe he want to work mine too. He does get paid for warranty work (right?), and if he's got nothing else to do (too cold for most cyclers, too dry for snow machines), he might just be wanting to do this.

IndianaTom said:

S76 said:

Took my clutch out today to see what's up regarding this thread.

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Did you like the clutch action before?

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I did not have the problems that some mentioned. My only clutch gripe was that it clunked going into first from neutral. But the clunk was minimal if you waited a few seconds, or non existant if you start in gear of course. I could always push the bike around in gear no problem. Normal operation according to most folks. I think the Synthetic oil I use makes the problem worse as it is pretty thin and lends little resistance to stop the spinning gears when you pull in the clutch. But, I just pulled the valve cover for valve adjustment and the motor is spotless like new in there so I'll stick with it.