This is my first post: be gentle. I've been riding my single-cross for about a year with 42/18 ratio. Love it, except the 'normal' bike guys fly by me on the flats and downhills. What if a guy could easily add another ratio [say 54/18] just by changing his left crankarm, and adding a chain [using flip-flop hub] ... and what if he could shift on the fly, by clicking a lever with his toe. Not for purists, and maybe [maybe] slight weight penalty ... but if the price were right, what do you think? Would anyone bite?