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A Smart Electric Bike: Taking the Copenhagen Wheel Out For a Spin

Posted by timothy on from the would-like-one-of-these-immediately dept.

New submitter mlamonica writes Bikes are a great way to get around the city. But what if it's just too hilly or far to commute by bike? That's where Superpedestrian wants to come in. With a license from MIT's Senseable City Lab, they're commercializing the Copenhagen Wheel, a bike wheel replacement that gives riders electric assist, and through 12 embedded sensors, lots of information on a smart phone app. I took the bike for a ride at the Cambridge office and offer this review.

1 of 136 comments (clear)

  1. Laws? by Anonymous Coward · · Score: -1, Flamebait

    Hmm. right. so,

    TFA says the wheel weighs 13 lbs, which is a ton,

    wrong. I hope this is a massive typo, considering that my car weights just over 1 ton.

    and it's rotating mass. I'd rather have a hub motor

    So what? Do you know that wheel mass has no effect except if you accelerate? So what are you talking about? Having the rotor be the wheel reduces all extra moving parts to nil.

    Also the topping out at 20 MPH is a little low. It would surely be useful in conditions of headwinds or uphills, where you cannot ride very fast, so that's nice. But for normal cruising, 20 MPH can be sustained by a fit rider who isn't elderly.

    and then...

    I can just do it on flat ground with no winds, and I'm 52.

    Please, don't contradict yourself in two sentences. I only 62 year olds that tide faster than you for hours at a time. 52 is not "elderly".

    20mph, in normal world terms is 32 km/h. 32 km/h is not exactly 'cruising speed' on a bicycle. You have to work at it to sustain this speed.

    It's far harder to ride 25 mph on a bike - I cannot do it for more than a minute unless assisted by hills or wind. Power demand is not linear with speed.

    25 mph is 40km/h. Just FYI, not many people sustain 40km/h on their road bikes in their Lycra shorts.

    http://en.wikipedia.org/wiki/D...

    Yeah, it's to third power. Going 2x as fast requires more than 8x the energy. If you ride a motorcycle, you are very aware of this as the wind is right in your face. Similarly, on a bicycle, going 25km/h tends to be easy on a calm day, but 35km/h is a little difficult - at least alone.

    Anyway, the REASON why there is a limit of 30km/h for the bike has everything to do with typical LAWS. In many jurisdictions it is ILLEGAL for a power-assisted bicycles to exceed 30km/h. If something goes faster and is power-assisted, it is no longer considered a bicycle (or power assisted bicycle), but a motorcycle (or scooter or whatever), and different laws and licensing requirements govern said vehicle.