Originally from a manga series in the 1970's, Skullman is considered to be one of manga's first anti-heroe, someone that would do a little bit of bad so at the end of the day, the good still prevails. In 2007, Skullman was adapted to an anime series with a live-action film for its prologue (pictured above) Skullman's choice of transport is a wicked looking motor bike called the Ryujin.
Whitehouse, a Japanese motor bike enthusiast blog has created Skullman's Ryujin bike used in the live-action film (Episode Zero). At the same time, they provided a Skullman Ryujin papercraft bike for the fans of the series. Follow the link below, scroll down a little bit to get to the goods (see pic below to know what to look for), there's also two other papercraft bikes in there that you might want to check out although it's not as interesting as Ryujin.
Skullman Papercraft - Ryujin Super Bike [whouse.jp]
Catbus 'Nekobasu' Papercraft [Realted Posts]
Super Robot / Mecha Anime Papercraft
Kitaro's House Papercraft
Honey and Clover Papercraft
Giant Robo Papercraft