Five race bikes built to break every rule — most of them barely got the chance to prove it. From a rotary engine that got banned to a Grand Prix prototype with no front forks that never even raced, these are motorcycling's boldest engineering swings. Footage credit for every clip is shown on-screen throughout this video. Subscribe for more machines the world tried to forget. #motorcyclehistory #racinghistory #motorsporthistory #onelungracing #motovlog #forgottenhistory #hondaelf #motoguzzi #hondarc166 #prototypemotorcycles #racingengineering #experimentalmotorcycles