[fastd]

I had a similar shake in mine; I have seen so much written about shakes at 60-65 mph on Club Cobra and elsewhere. Mine started at 60 and went to about 90! I changed the tires; shake range tightened a little from 70-90 mph. Road force balancing didn't really help but it turns out it wasn't really done right; ultimately I got them balanced 3 more times after other things were fixed until everything came together.

The major reason for my shake was unbalanced brake rotors (the thickness of the vanes were much different from vane to vane and top to bottom). I think each situation is different; need to check shocks, tie rods, steering rack, etc. until it gets sorted out. Unfortunately, no one answer.