[M & M]

Bish,

Are you balancing the tires on the car or off? By you prior post I am assuming on. If you can find a tire shop with an old style wheel balancer that will balance them while still on the car you might lick the problem. That way you can get them spun up to the speed you are seeing the problem at.

Often times balancing them off the car will not not give a true balance because of several things, in your case it could be the knockoff for example.

Unfortnuately not many shops anymore have a balancer that will work with the tires on the car.

Best of Luck,
Mike