I have Michelin RP 2's. The rear is wearing very evenly and well, lots of tread left, but the front is not. The harder compound in the center is not wearing down nearly as fast as the softer sidewall compound. I am not a "fast" rider but not a lot of the roads I ride are a straight line either. This wear pattern on the front tire produces a weird tire profile/shape which in turn gives kind of a weird sensation turning in. Is this what they call "cupping"? Should I replace this tire - it still has some tread left? Any suggestions on a good front tire?