Have a closer look at the UJ. Twist and pull it for signs of play or roughness.
I pulled the UJ yesterday, no signs of play or roughness. It was in good shape. I replaced it in July of last year (18,000 miles ago).
Like John said replace the alternator drive dampener rubbers.
Have you been lubricating all the drive splines yearly? From the motor output shaft, drive shaft, to the rear wheel?
If the dust you referred to is red it is lack of moly paste on the drive splines but your words didn't make clear if the brake dust on inner rim was inside the drive hub or not or color. Black would be brake dust.
All of the splines are lubricated with Molly often, from the output shaft to the rear wheel. This was last done when I did the UJ in July last year. The dust was black and was on the wheel rim where the large rubber boot from the final drive meets the wheel rim. I don't seem to recall seeing that much dust there in the past, but then again, most of my miles since then have been loaded down pulling a Bunkhouse that we had.
Just a thought....carb synchronization? Another fellow had small vibration from his alternator. He simply pulled unit back enough to CHANGE POSTITON of drive impeller in rubber blocks....vibration disappeared. ....papasmurf
Just asking, if it were a carb sync issue, wouldn't I get the buzz when the bike is in neutral and I took the motor to the RPM range where I am experiencing the buzz?
Still IMO the alternator dampers are exactly the first thing to replace "just for drill".
The rubber becomes hardened and non-resilient.
The rubber dampers seem to be the common theme here. I replaced them October 16th of 2010 (36,000 miles ago) when I put a HO alternator in from Ken Hemming. I later replaced the HO alternator with a Compufire in April of 2012 (27,000 miles ago) but did not replace the dampers at that time.
I will replace them, then report back. Thank you for the help guys.