No doubt, Japanese superbikes of the late '70s are damn sexy. They've not got the plastic feel of current models, and as such have almost unmatched character. However, they need a proper custom workshop to revitalize old glory. The AC Sanctuary Kawasaki KZ1000 is a killer example. The Japanese customizer turns relics into contemporary powerhouses. It'll cost $42,000 to get one. [Bikeexif]