I have a 05 ultrasport and i bent up 2 rims. 2 months ago i bought 4 new lorenzo wl21s(225/40/18) and put hankook ventus v4 tires on them. I havent been able to keep them balanced since. They balance great at the tire shop but as soon as i drive off they come right out of balance. It feels like i'm driving in baja. The tire compnay wants me to purchase goodyear eagles and swap out the hankooks but i'm just want to make sure that this problem is in fact the tire and not something else! Any and all advice will be greatly appreciated!

 

It may caused by the new wheels you installed. Aftermarket wheels are drilled with a larger hub than stock Audi wheels and need a spacer to fill in the gap to keep the wheel from wobbling.