(Heavily edited 7 December, 2013, on the occasion of the wheel’s commercial release).
I wrote a scathing review of a prototype of The Copenhagen Wheel that I saw in 2011. However, now the wheel is available commercially, it seems churlish of me to leave that text here when, on balance, the wheel is a good thing for cities and cycling.
The prototype was too weighed down with sensors, with the idea that every copenhagen wheel in a city would contribute to a data cloud so the next rider could avoid bumps and air pollution. I explained my concern with reference to the prisoners dilemma, arguing nobody would fit a heavy hub to their bike, to benefit others, but with only disadvantages caused to themselves. Technical advice I received from a boffin friend also caused me to doubt the value of regenerative braking on bicycles. But from what I can gather, the commercial version is lighter and stripped of a lot of excesses.
The story of this wheel’s development is a case study in web-based self-promotion—that I’m also involved in. Before it was ever perfected, the wheel enjoyed waves of viral attention on coolhunting blogs, and was even the subject of ridicule on television (Weeds, series 7, episode 6.) But now real customers (like you, I presume) are considering buying the marketable version, it’s time my own mockery of the prototype got pulled from the web. If you’re considering buying one, because they look cool, are dead-easy to fit to a bike, and will be an incentive for you to ride more and drive less, then don’t be a cheapskate. You will recoup the purchase price by spending less on driving, gym fees and heart operations.
Another option you might consider, is a plain old e-bike conversion kit. The Copenhagen wheel puts the weight of the battery into the wheel, turning your bike wheel into a fly-wheel, with energy-use implications each time you want to get it spinning again after stopping. You will also have to brake a lot harder. Remember too that batteries on e-Bikes don’t last forever. After two years, when the battery dies, the one in the Copenhagen will be harder to replace than one attached to your pannier rack.
Note: the comments below pre-date my major edit on 7 Dec. 2013. There are more old comments over at my livejournal site, that I no longer maintain.