I'm 6'3" and have all the families of H-D's. I have no problems riding 2K on the Street 750 or 4K on the Sportster Super Low on multi day tours with one day totals of 7 to 9 hundred miles.

The only one I'm crowded on is the 16 RGC CVO Ultra they moved the operator forward to give the passenger more room but I don't ride two up. Also they pulled the bars back and they almost dig into my belly and they pinned them in that position.

I like the feeling of whipping smaller bikes around.