Gaijin sent a photo of the Honda Gathers M waterproof handlebar mounted navigation system. From what I could find, this has evidently been available for a little while for the Forza scooter and may be available now as a separate system. (I was reading translated Japanese so this could be a kitchen appliance for all I know.)
Update: Gaijin Biker confirms my translated description, the navigation system can be installed on any motorcycle.
photo courtesy Gaijin Biker