My '97 with 10k miles developed a high pitched "weeezzzzhhh" whirring sound both under way and in neutral.  I had it trucked home and the motor is apart on the work bench.  I found non-magnetic flakes in the oil pickup screen and pan, see included photo.  These are soft metal flakes found only in the pan and screen, none in the gearbox, so I'm not worried about the tranny  ball and roller bearings, but the centermost crank shell bearings are toast, see photo, so I'll be replacing all the crank and balance shaft bearings and the rod bearings soon as I figure out what the tolerances are. 

BUT the freaking hell of it is that I can't find any evidence of soft non-magnetic metal being galled or worn on any inner case surfaces!  I've been over the cases with a magnifying glass, particularly the cam chain well and the tach drive journals and there is no evidence of metal being removed.  The crank and balance shaft shell bearings didn't fail, they just have evidence of small flakes embedded in them that got through the pickup screen.  The rod bearings didn't fail.  All the cam journals look fine.  The gearbox ball and roller bearing journal look fine, no evidence of keeper pin failure.  It's a head scratcher.   Someone gimme a clue as to what might have failed that could have made that sound, that is non-magnetic and that could have left those flakes.

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But the center bearings are bronze. If you got that - it will be golden in color ... unless you have it burnt - then its darker gold ...

Yours looks like you lost a clutch basket.

Cool.
Srinath.

Quote from: The Buddha on May 13, 2013, 03:31:31 PM
But the center bearings are bronze. If you got that - it will be golden in color ... unless you have it burnt - then its darker gold ...

Yours looks like you lost a clutch basket.

Cool.
Srinath.

You are referring to the clutch bushing?  I have the clutch apart and there is no evidence of damage to the clutch basket or hub.  The flakes are aluminum colored.  I'll check the clutch again but keep in mind that the sound occurred when the bike was in neutral and the counter shaft was not in motion.