I'm sure this has been covered a dozen times but this is my first rear main seal replacement. The bike is a '84 R100. I replaced the rear main seal following the steps in my Haynes manual. After putting it back together I get a chirping sound from the clutch area at idle after it gets good and warmed up. When it cools after stopping for a few minutes it no longer chirps until it get hot again. It stops when revving the engine but returns at idle. I called Bob's BMW and spoke to a tech there who said if I let the crank move forward the thrust washer can slip off it's pins and get wedged in between the flywheel and bearing. It would have been nice if the Haynes manual had mentioned this. I removed the clutch, the brand new rear main seal and right jug to look at the bearing. Both the front and rear thrust washers are still pinned but there doesn't seem to be much end play in the crank. Anybody got any ideas on what I need to check next? I was a Honda / Yamaha mechanic back in the 70's and have done lots of restorations but this is my first airhead. (I'm digging it!) Any help would be appreciated. I checked the airhead tech pages but my clutch and flywheel doesn't look like R90 in their pictures. Thanks in advance.