I had a wobble at 63-70 and wouldn't go higher because of it. I added hand gaurds and removed bar weights and it's gone. Although I've only gone up to 80mph there was no more wobble. If that is coincidence or not I don't know.
I have cruised along at 160kph smooth as a whistle, no shake or anything, still running stock rubber. Not even any buffeting since l adjusted my stock screen up 3mm at the top, ithas even cleaned up the buffeting in dirty air a lot. Going to try 3mm on the bottom and 5mm on the top and see how that goes.
I normally only get wobble over 85 mph and it's very subtle. However, I notice if I grip the bars tightly I tend to get some shimmy over 65 mph. Loosen up that death-grip and see if it helps.
I placed a rubber grommet under each of the top screws on the factory screen to change the angle of it. I hope by placing the 3mm grommets on the bottom and using some 5mm grommets on the top, it might work like the old BMW's that had a raised screen, causing a vacuum underneath, effectively getting rid of the turbulence behind it. Hope this helps, if interested, l can take some photos.