The trouble with folding bikes is that when you unfold them, they're unmistakably folding bikes.
For all their hipster commuter cred, with their small wheels they're not as stable as full-size bikes, and have a bumpier ride. Italian engineer Gianluca Sada reckons that he's found a better solution – a full-size bike that folds down to the size of an umbrella.
The Sada Bike concept has an ingenious design – its hubless wheels are anchored to the frame by a quick-release clamp; pop them off, and you can fold up the frame by pushing on the seat. The result is a folding bike that's just as compact as a Brompton, with the 26in rims of a full-size bicycle.
Yes, you have to carry those wheels along with the bike frame, but Sada's come up with a neat solution to that problem, too; the wheels form the structural support for a special backpack, with their spokeless design allowing for more storage space in the bag.
The Sada Bike's design does raise a few questions, though. The hubless wheel design is convenient, but it'll inevitably reduce the strength of the wheels, and make them more vulnerable to being bent out of shape. Sada's video of the prototype bike cuts away each time he's about to fold it up, suggesting that it might be a more time consuming process than he's letting on. And while the frame is indeed smaller than an umbrella when folded, pics of the folded bike don't include the wheels or handlebars – both of which add bulk to the bike.
Still, Sada deserves credit for actually taking his concept as far as a working prototype. And the design throws up some interesting possibilities – a commercial design, made from lightweight, strong materials, could make Sada Bike riders the envy of other commuters.