So I had one front wheel bearing replaced and now I have a bad shimmy in the steering wheel like one of the wheels is out of balance. So I had all the wheels balanced TWICE and I'm stumped. I've looked at both front rotors but I can't tell if either is warped, but everything was fine before I gave it to the mechanic for the wheel bearing. 97 Maxima SE with a stock suspension. Any ideas?

Edit: I also failed to mention I have a BBK kit installed using the centering rings, Cobra rotors and steel 300ZX calipers. I took the caliper and rotor off the wheel where the bearing was replaced and all looked fine. I'm going to see if the ring was seated correctly again. If the rotor is seated incorrectly I would imagine I'd get a pretty decent shimmy. Especially since these rotors are quite heavy.