Vampire Hunter D

i was thinking about making a lifesize model of D's horse that i could actually ride!! was gonna try making it out of an old bicycle of mine & it would be rigged so that every time i pedaled the bike, the horse's legs would move, without all the wiring that comes with animatronics! not really sure how i could pull that off but im open to suggestions! lol! i also am having trouble on how to adjust the brakes on my old bicycle so that they dont stand out too much inside the horses mouth? as i plan to have the reins connected to the bike's brakes so that when i do yank on them it'll come to a complete stop! but i dunno how to accomplish this task, especially since i need to salvage the brakes & everything in some way or another to make the whole project a success. anyone who sees this plz dont hesitate to send me a note on da with any suggestions u might have on how i can go about this project safely & correctly!!