If by the black band, you are talking about the dustcover around the center of the drive unit, it never looks like it is all the way on... there is a groove showing that you think should be under the dust cover, but it doesn't go under the dust cover. Had the same worry my first time too.
The other thing (question) is, did you
not tighten the four nuts on the drive unit connection until the very last step of the reinstall? If not, jack the bike up, loosen them up, spin the wheel, and tighten them again. This is the main point to ensure you got a good spline mate-up.
The four bolts/nuts on the right side of the pic.
