Very clever how you use pedal power to inflate the pontoons and then that same assembly drives the prop. Not signing off on The Shuttle Bike being sturdy but coupled with a folding bike and handlebar mustache and you could be commuting at land and sea at peak hipsterness:
“For fun or for practice, SHUTTLE BIKE KIT® does not require special skills : it can be used by everyone, even if you are not a good biker or swimmer. It allows you to experience unique emotions , exploiting the opportunities of a real water transportation respecting the environment.
SHUTTLE BIKE KIT IS A 100% MADE IN ITALY , HAND MADE, HIGH QUALITY PRODUCT. IT IS SPECIALLY DESIGNED TO OFFER OPPORTUNITIES FOR SPORT, FUN, AND ADVENTURE YOU NEVER THOUGHT COULD BECOME REALITY. FOLLOWING FEW AND EASY STEPS YOU WILL TRANSFORM YOUR BIKE IN A REAL WATER-BIKE : YOU CAN CARRY IT IN A SIMPLE BACKPACK, REACH THE WISHED PLACE AND … START TO PEDAL ON WATER!” images from www.shuttlebike.com