@shanr You will need to rotate this Empty at the same time:

If you want the right wheel to turn in the same direction, you will need to Apply the Mirror Modifier and Duplicate the Empty to the other side and use that as the control in the Simple Deform Modifier…
At some point we will just have to Apply all the Modifiers and then there wouldn’t be any problem with Transformations any more, but I’d leave that until you are absolutely sure that all the modelling is done (on the wheel/tire!).