I did a couple of things to minimize vibration on mhy 2003 naked Bandit 1200. First I made sure all the motor mounts were tight and to torque spec.
Then I carefully balanced the carbs. I then installed Manic Salamander bar end weights to quell the vibration with very good effect. Finally I went for a 16 tooth countershaft sprocket to drop the RPM a bit at highway speeds. This had the added benefit of correcting most of the speedometer error.
I can ride at 70-75 MPH in relative comfort now and with minimal vibration, although I can still detect some if I'm not wearing gloves.