While we've already seen folding bicycles that pack down into a pretty tiny package, such small-folding bikes usually have at least one limiting factor – puny wheels that limit speed and road-worthiness, not to mention aesthetics. The Sada Bike, however, features full-size 26-inch hubless wheels, yet is about the size of an umbrella when folded.
Italian designer Gianluca Sada has been working on the bike since 2008. He completed construction of an aluminum alloy working prototype three years ago, and is now looking for investors to help bring it to production.
The folding action is initiated simply by pushing forward on the saddle. The wheels detach and aren't part of the umbrella-sized package, although Sada has plans for them.
He envisions the folded bike being carried in an included backpack, and the two wheels would serve as the supporting structure of that pack. Because they have no hubs or spokes, there would be room inside the backpack to carry other items, besides the folded bike frame.
Alternatively, the pack could be pulled like a wheeled suitcase – converting it to that configuration would involve releasing a central hinge to widen its stance, and extending an included handle. The bottoms of the bike's wheels would protrude through openings in the bottom of the backpack, allowing them to also serve as its wheels.
The prototype bike can be seen in action in the video below.