New York's Citibike bike-sharing program may be laudably green, but pedaling isn't always easy.

Now, there's a startup that hopes to give riders a little push.

ShareRoller is an add-on electric motor for Citibikes that hopes to fund itself through Kickstarter.

Jeff Guida--the device's inventor--told Gothamist that he views ShareRoller as a way to decouple bicycle commuting from exercise. The add-on caters to people who value the convenience and low environmental impact of cycling, but don't want to sweat through their work clothes.

ShareRoller consists of a small electric motor, a battery pack, and a controller, packaged together in a laptop-like case. The battery powers a roller, which drives the bike's front wheel through friction.

ShareRoller add-on electric motor for New York City Citibike.

ShareRoller add-on electric motor for New York City Citibike.

The final version is expected to weigh between 6 and 7 pounds.

ShareRoller says its standard battery pack will provide an estimated 12 miles of range, while a larger version will provide 20 miles of range, to be offered as an option. A full charge takes 1.5 to 2 hours.

Riders simply clip the case to the front of a CitiBike, and attach the controller--connected by a cord--to the handlebars. A plunger on the controller acts as the throttle.

The motor produces 750 watts (around 1 horsepower, or roughly one one-hundredth of the motor in a Nissan Leaf electric car), enough to propel a Citibike up to 18 mph.

However, the rider must get the bike moving with the pedals before the motor kicks in. Still, the extra grunt could be especially helpful on steep hills.

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There's just one problem with the ShareRoller idea: It's illegal.

New York City banned electric bikes last year, although they had been outlawed already under previous legislation.

However, Guida told Gothamist that he hopes to exploit an exception in the city's Local Law 40, which permits electric bikes that require rider assistance.

Modifying bikes is also against Citibike rules but, since the ShareRoller is removable, it might pass muster--although riders have to carry it around with them.

Before the legal questions come into play, though, ShareRoller needs funding.

To get things rolling (no pun intended), ShareRoller hopes to raise $100,000 by the end of its Kickstarter funding deadline, which is today.

At the time of publication, it had raised roughly half that amount. To back the project, head over to ShareRoller's Kickstarter page.


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