By moving the hubs out, reversing them, (if necessary) and reversing the rims, (if necessary) you should be able to get them almost outside the rear fenders. My neighbor's B2150 uses the same setup as my B7100, and he has his rear tires completely outside the rear fenders. Looks a little funny, but it's stable. You can kinda see how far out they are in the pic, only one I have of his setup.