I can't give you an engineering reply, but I acn give you another example...
I have raced bicycles, and for aerodynamics, a solid disk wheel is best. They are frequently used on front an rear for indoor track racing- because there is no wind. Outdoors, it is common to use a disk rear with a spoked front, either conventional spokes (low spoke count) or bladed carbon. Even a rim with a deep cross section can give you a noticeable sail effect in a cross wind. So, if it causes an adverse effect on a lightweight bicycle, it should cause a similar effect, though not as strong, on a heavier V-Rod. I know it is there, but my old Kawasaki was affected by crosswinds too, so..... let the flames begin, I am wearing my nomex underwear.....