MC28 dry clutch. When I rev up the engine in Neutral, a loud shreiking dry bearing at high speed type metallic noise is heard from the clutch area. It only lasts a maybe just a bit under a second and is gone. It is only heard when revving up and not a low RPM.

I removed the clutch cover and found that the inside had very light rub marks on the plastic from where the screen is peened over. It looks as if it's been that way for a while because the screen has a touch of rust where it was rubbed. The pressure plate bolts were tight. Hub nut- tight. Basket bolts- tight. I removed all the plates and found scrape marks on the ears of some of the fiber plates. Is this normal? The basket has wear - indentations from the ears of the fiber plates. No cracks in either hub or basket. No warped plates. Some blueing on steel plates. It looks as if I'm the first to crack it open. Still has damper plate with rubber in a couple of spots. Is every ear on the innermost fiber plate supposed to have them, or just a few?

I started and revved the bike without any clutch plates and the noise is completely gone. It does not sound like water pump bearing issue. Noise is heard either in clutch hub/basket area or just behind the large seal plate.

Has anyone experienced this. Advice is always appreciated.

Thanks

I forgot to mention: If you pull on the clutch shaft with everything removed, there is no excessive in/out or side/side play

There's only four dampers, so don't worry about that.

Does the noise happen whethe the clutch is engaged or not (ie lever pulled, or lever released)?
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Last edited by Dave Ett on Sun Jul 01, 2007 6:40 pm; edited 1 time in total

with the lever out. I just got finished taking the side cover off. Is the trans pump gear supposed to be loose and wiggle? Also, is the water pump supposed to have some resistance when you turn it manually? Everything else checks out ok. No rub marks or anything abnormal was visible? I'm stumped. I took a look at the dampers and the sides that contact the basket are almost flat with the clutch plate ears. There are 4 of them by the way. I read somewhere that it's recm'd to remove the dampers?

How does the water pump gear come off by the way?

Its normal for the trans oil pump gear to be a bit wobbly. The water pump will be quite hard to turn by hand as it uses a mechanical seal.

To remove the water pump shaft you have to hold the shaft in a vice (with soft jaws) and then use a 12mm socket on the impeller. Once the impeller is removed the shaft will slide out.
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If I have to take the carbs off once more...

Any ideas on the noise? Would worn dampers or notched clutch basket grooves somehow cause this?

I have to keep remembering that the noise was gone with the plates removed and just the hub and basket.

I might have got side tracked with taking the side cover off.

I just don't know if replacing plates and basket will get rid of noise?

How bad are the grooves in the basket?

Remove the dampers if you want more jangle from the clutch when in neutral with the clutch lever released!

Any pics to help us?
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FJ1100 Sporting relic
GTS1000 oddball

Tough one this.

Did the noise just appear over night or what?

Did you start the bike without the plastic clutch cover on? Noise still there?

You could try looking at the pressure plate bearing. I've seen several that have seized, but I can't say that I've come across this shrieking noise you're on about.

Does the gear shafts turn easily by hand?

Can you see any obvious signs of any components touching the case etc?

Need to be there.

the noise did appear overnight.

I started the bike without the plastic cover, still there.

The pressure plate bearing is a little tough, but it only is utilized when the lever is pulled in from what I can tell. There is no pressure against the inner bearing race without the lever pulled in.

Gear shafts spin easily

No visible signs of rubbing

Bearing in the mind the noise vanished when you stripped the plates out, I'm wondering if the grooves in the basket are keeping the friction plates apart slightly, allowing them to slip and cause the screech.

Are the friction plates and steels in the right order?

Got a pic of the basket?
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BMW F800GS Bumblebee
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FJ1100 Sporting relic
GTS1000 oddball

What is the correct order?