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