High Speed Wobble

[pancho]

I was passing some vehicles the other, really pushing it, and had a wobble start at 85 or so,, it continued until I got back in the lane and was able to reduce the speed a little. Kind of scary as I had to keep on going and it felt as if more speed would make it worse.

Wondering where to start looking for the problem?? shock bushings are good and both wheels are balanced with beads.