So finally got my GPS on the bike to test that weirdness which I coulda swore was occuring at 75mphs and I was right. At 74mph my gps indicated 1mph off. accelerating lightly through the 75mph zone I got to 81 before it read 76 on my speedo (AH HA i'm not crazy!) as I proceeded it continued to get more off as I went at 91mph GPS registered speed I was reading 82 MPH on my dash time to send a shout out to the dealer and see what they say. Now at thoughs speeds I need to be carefull anyways but dang 10 mphs could mean making a corner and not.
The speed sensor is on top of the transmission case. I suspect it is a Hall Effect transistor type pickup. It is triggered by the teeth on the left most gear on the transmission input shaft. It seems either the sensor is flaky or the instrument panel is having trouble tracking the signal at higher speeds.