I must confess that I was hoping to see something like that since I came to a country with such a big motorcycle production; alas, I only saw it for the first time last weekend. It is a six-cylinder, 1500cc Honda Valkyrie reborn as “Ryujin” (龍神) i.e. "Dragon King" by some Japanese custom shop. From another service area on the Joban (常磐自動車道) highway.
(For a bigger version of this picture both in color and black and white, check my "Japan Arekore" set on Flickr)