Sorry, I guess I should be more specific. The vibration seems to start up when in 5th or 6th gear, and more pronounced in 6th when under load. My gut feeling based on about 40 years of pulling wrenches on commercial vehicles is bad tranny bearings, but I have heard of so many different causes of vibration issues on these bikes that I didn't want to pigeon hole the problem just to the tranny. At about 110 to 130 kms it really gets bad, and if I roll back on the throttle it quiets down a bit and as soon as I cracks the throttle again it comes right back. At idle and lower speeds and gears, it seems fine, just the normal rumble of a twin. I wanted to throw it out there to see what the rest of the masses had experienced if anything.