This is more of a tip than a question that might help you fix any issues you may get while using the curve modifier. I kept on getting a twist after I rotated my cure to fit the wheel. Turns out when you rotate a curve the handles also get rotated and that gives you a twist that then deforms any object that follows that curve. You can get around that by going to the Curve Options tab in the Properties Panel and then selecting twisting to Tangent as opposed to minimum before you rotate your curve so they won't get affected by your rotation.
Hope this helps.