Engine vibration, OEM bars and Weld 86 plate
Here is my solution to the 4700 rpm vibration with the engine bars and Weld 86 skid plate. I installed a brace from the engine guard crossbar to the skid plate. Used a 6" metal strap and a 3/4" rubber-lined P-clamp (cable clamp) from the hardware store. I have some very small vibrations at 3200, 4000 and 6000, but nothing like before. Your results could vary, as I have also mounted some WARN brackets to the bars for driving lights (no lights yet). Just doing this moved the vibration from 4700 to around 4200 rpm.
Hard to tell in the picture since I painted the strap black, but it is bent slightly and goes on the bottom/front of the skid plate. Don't know if it helps, but I also used rubber washers mounting to the plate since I didn't want to introduce any new vibrations or buzzes.
2014 V-Strom 1000 - Desert Khaki
2011 Burgman 400
2007 Honda Helix
2013 V-Strom 650 - sold