I've seen several Streets modified into a pure dirt bike configuration. Typically the first thing is to change from a belt drive to a chain drive (belts are better for the street and chains are better for dirt) and along with changing the springs, shocks and tires, offing the fairing, and a few other mods you have a great dirt bike. Might also switch to spoke wheels and tubes for repair purposes (which is why a chain is preferred over a belt).I watched Avengers: Age of Ultron last night. Captain America was riding a 750 like a dirt bike through the forest, I dont think that would work. Still pretty cool though to see Cap on the Street again.