On July 11 I was riding along the prairies of South Dakota when I had a nice straight stretch of road.
I felt the need...the need for speed (Top Gun reference).
I opened Dolly up and kissed 120 and instantly let go of the throttle to let her start to slow down.
(I know. Your comments will be something along the lines of "what a dumba$$", but remember that these bikes were made for the Autobahn and should be able to handle a kiss of high speed. I have had Dolly faster for longer in the past.) I felt very comfortable on her. We were 2475 miles into a 5500 mile mancation.)
Between 110 and 108 mph, I had a very violent, and rapid, head shake. It was so violent that I could not hold on to the bars. It was such a rapid (harmonic) increase that I could not hit brakes fast enough.
Yes, I went off the side of the road. I think ATGATT and my bike saved me. I road Dolly for three somersaults before being ejected and flying 200 more feet, eventually ending up in a prairie field. Dolly took the initial impacts for me.
I left Dolly behind in SD.
I suffered a fractured left foot, broken right knee bone (patela), two ribs on the left side, and 10 vertebra...nothing structural.
I was helicoptered to Rapid City Regional and spent a week there where the fantastic staff watched me heal naturally, no surguries.
My tires were inflated to 42F/48R. I was light loaded because all of my gear was at the Horsethief Campground. No cupping, No Metzler roar. HyperPro shocks. Riding solo.
I replaced Dolly with Phoenix Helena a couple of weeks after the accident and have since ridden approx 380 miles spread out over 2 weekends. I am much more wary of head shake now. I don't think I need to go triple digits, but I am still comfortable riding Phoenix in the 80's and 90's.
This is my lesson learned. I hope it helps others recognize that head shake happens at speeds greater than 30-45 mph and the effects are much greater and faster.
Ride safe and keep the shiny sides up.