From wind pressure alone?
well probably from vibration due to crappy roads near my house as they redo the normal ones. AND a few runs in the triple digits... well more than a few.
noticed it today. the normal short vibrations went into long oscillations... i knew it wasn't right. I was going to make sure the bolts were tight when i got home.... never made it before the dash fell into the wires behind the light at 100mph
well that was the last speed I saw before...
anyway, learned to ride with no speedo and no tach
I think I was carrying higher corner speeds as I wasn't looking for indicators, but was feeling the bike better.