Wow! Wonderful Criss! Good job!
You have to talk with Bomber about this. I think this is pretty awesome and interestin' and HAVE TO be implemented for V5
Jesus, actually, it's one of the most greatest finds out there if you think that these are the "unused" sprites directly used by SEGA. Not only the bike stuff, but EVERYTHING you've found. Also, they could help you with the sprites and pixels stuff.
Again, talk with Bomer and his team about this awesome stuff.
"Recuerda, respeta las opiniones y criticas de los demas, para que ellos respeten las tuyas, todo depende de puntos de vista y formas de ver las cosas