I don't know what would cause a vibration manifested at the left mirrror. You primary drive connecting the tranny to the sprocket is on the left side. Maybe that could be screwed up in some way. My first guess is that the mirror itself is the culprit.
What do you feel? Does your left hand get vibrated 3x your right hand or is this all happening at the mirror level? Does your drivetrain feel like it is vibrating in an excessive or odd way?
I Rode Mine-Little & Big Sturgis/Milwaukee/Tomahawk/Branson/Pig Trail/Push Mountain/Mt. Nebo/Toothpick/AR7/AR21/ Skyline/BRP/Cherohala/The Dragon/Around Lake Michigan 1000 miles in 21 Hrs. 2004
2003 FXDWG Black - Skyrider - Dragonslayer
What a long strange trip it's been! UNFCKNBLVBLE!