Many of the world’s bike share schemes — like London’s Boris Bikes — use identical bikes and docking technology from Canadian company Bixi. That gave inventor Jeff Guida from New York a simple idea: why not bolt an electric motor to a Bixi bike and turn it into an e-bike?
The result of eight months’ development is the ShareRoller, an electric-assist motor that mounts on the bike’s triangular docking bracket and drives the front wheel. ShareRoller puts out a whopping 750 Watts in its US incarnation though UK and Canada versions will be power-limited to keep them legal. Or somewhat legal. Maybe. But we’ll get to that in a moment.
First, though, Jeff's looking for $100,000 to get the ShareRoller into production, and, almost inevitably, he's turned to Kickstarter to do it.
Here's his fund-raising video:
On the device’s Kickstarter page, Jeff says something that will resonate with everyone who’s ridden a Boris Bike: “The idea for ShareRoller was initially conceived in June 2013, right after CitiBike launched in NYC. One ride on the 45-lb 3-speed bikes was enough to spur the search for motor assistance.”
Boris Bikes. You can’t damage them, but at least they’re heavy.
So Jeff “abducted” a bike, and had the ‘Aha!’ idea of mounting a motor on the docking bracket. After multiple rounds of design and prototyping, the result is a briefcase-sized assembly of motor, batteries and drive roller that will propel a bike at 18mph without pedalling for 12 miles with the standard battery and 20 miles with the extended-range battery.
ShareRoller charges in 1.5 to 2 hours and uses batteries from the same company that supplies electric car maker Tesla. It’s about the size of a ream of A4 printer paper and weighs 6-7 pounds. That may be less ‘portable’ and more ‘luggable’ but if you live and work close to docking stations it’s not going to kill you.
Unlike many Kickstarters, this isn’t a rough proto and a bunch of CAD drawings. Jeff says the ShareRoller is a “fully-developed, late-stage pre-production product”.
Jeff worked in management consulting and finance before turning his hand to inventing, but studied electrical engineering in college. But what’s enabled the ShareRoller to go from idea to production-ready so quickly is a technology that’s turning many industries on their heads: 3D printing.
A $20,000 investment ina 3D printer allowed him to “hyper-drive the design-prototype-test-redesign loop”.
“We could have spent that $20k on a snazzy video instead, but we felt this was a much better use of our limited funds,” he says on his Kickstarter page.
ShareRoller won't just be for use on Boris Bike-style hire cycles. After all, there are only a bit of 20,000 of them in the world. Jeff already has prototype mounts that will fit a kick-scooter and a Brompton, and plans to expand ShareRoller's application to a wide range of bikes.
The idea of jumping on a Boris Bike and getting from A to B at 18mph, instead of the more sedate pace the bikes usually mandate might sound appealing, but there are a few possible snags for UK use.
For start, electric bikes here have to be pedal-assist. If all the motive power comes from the motor, then it’s a motorbike and you need a helmet, licence, registration and all the other regulatory gubbins intended to keep petrolheads in check.
New York has similar rules and Jeff aims to get round them by preventing the ShareRoller from working if you’re stationary. You have to pedal away before the power kicks in. But there doesn’t seem to be any way for ShareRoller to tell whether or not you’re still pedalling once you’re under way.
Then there’s the power. In the UK electrically assisted pedal cycles — to give them their official designation — are limited to 200 watts, which the ShareRoller’s 750 watts clearly exceeds, and the electric assist has to cut out at 15mph.
A ShareRoller that puts out just 200 watts might be a bit anaemic away from the lights but the power restriction should massively extend the range (and its acceleration will still be no worse than most cyclists and a lot quicker than an unassisted Boris Bike). You might not cover the 12 miles from the eastern edge of the Boris Bike network at East India to the western at Ravenscourt Park in a single 30 minute hire slot, but you should have enough juice for the return journey.
You'll have to keep an eye out for TfL staff, though, in case they decide to enfore the rule that users may not "add or attach accessories or trailers to the cycle."
John has been writing about bikes and cycling for over 30 years since discovering that people were mug enough to pay him for it rather than expecting him to do an honest day's work.
He was heavily involved in the mountain bike boom of the late 1980s as a racer, team manager and race promoter, and that led to writing for Mountain Biking UK magazine shortly after its inception. He got the gig by phoning up the editor and telling him the magazine was rubbish and he could do better. Rather than telling him to get lost, MBUK editor Tym Manley called John’s bluff and the rest is history.
Since then he has worked on MTB Pro magazine and was editor of Maximum Mountain Bike and Australian Mountain Bike magazines, before switching to the web in 2000 to work for CyclingNews.com. Along with road.cc founder Tony Farrelly, John was on the launch team for BikeRadar.com and subsequently became editor in chief of Future Publishing’s group of cycling magazines and websites, including Cycling Plus, MBUK, What Mountain Bike and Procycling.
John has also written for Cyclist magazine, edited the BikeMagic website and was founding editor of TotalWomensCycling.com before handing over to someone far more representative of the site's main audience.
He joined road.cc in 2013. He lives in Cambridge where the lack of hills is more than made up for by the headwinds.