Take your tires to a tire shop with a Radial Force Balance machine. They are rare, and hard to find. You may have a hard spot in the carcas that is noticeable, ot you may have the "High" spot on the tire aligned with the "High" spot on the rim. If the problem is RFB (or RFV), put the hard tires in the back, and the smooth tires in the front. Max is probably about 20 lbs of variation. If the problem is the second, unseat the tire from the rim, turn it 90 degrees, and try it again. The high spot issue is why many tires have a little dot at one spot on the bead.
See the Hunter website:
Hunter GSP9700 Wheel Vibration Control System
Hope this helps