There have been tons of reports of cupping and noise with the "MultiTread" Dunflops since they were introduced, more so in the first couple years and less recently. But that doesn't preclude the possibilities of other causal factors, like improper tire pressure, improper tire and wheel balance, defective shocks, etc. I'd suggest making certain you're running the proper tire pressure (check cold inflation often, like weekly and whenever there is a large change in ambient temperatures in your area). See your friendly dealer ASAP while the tires are still in warranty; hopefully you have a good dealership versus the ones who blow everyone off with "that's normal" or "they all do that".
Regardless of any comments by dealership personnel, Dunflop personnel, or H-D personnel, cupping is not normal. And even if it was normal, it is not acceptable, which is the important part.
Good luck.
Jerry