I've got to drive it over to beyond Burnsville NC this weekend, a nephew that's a small engine mechanic is gonna ride w/me to a family function maybe we can figure this out
maybe as simple as out of balance front wheels - would'nt be surprised. I got the backs balanced right off as I was looking for a good used tire to match - lucky the tire dealer had just one so had it mounted to replace the balding tire and spun 'em both.
I've got an idea it's front wheel vibration but as long as steady speed does'nt manifest, just when slowing from 45+ a bit down to 35 or so. from higher speed doesn't do it, the threshold is around 47mph down.