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Terence R. McCain researched how to build a bike that could help him haul supplies from town to his home. He decided he wanted an electric cargo bike. An energetic retiree, McCain had to go out of state to find a bike shop with “experience selling several models of cargo bicycles, and retrofitting electrical systems on bicycles.” He shares with us his experience designing this custom electric cargo bike, which he is expecting to be delivered in January.

Like many Americans, I began riding a bicycle as a kid. I still like bikes. I’d love to use a bike for local shopping. The grocery store is less than 2 miles from my house. Wal-Mart is 5 miles. Downtown Warrenton, Virginia is less than 3 miles away. There’s really no reason to use my van for most of those trips, except for one little thing.

My bicycle – an 18-speed mountain bike – doesn’t have a trunk. I can’t put 80 lbs of groceries on the bike because there’s no place to put them. And if I could put them on the bike, the local hills would probably defeat me. I’m not as spry as I used to be.

Maybe an electric bike would do the trick?

Lots of electric bikes are coming onto the market now, and that’s a good thing. But they all seem to have one thing in common: still no trunk. Most have enough power for the rider, and no more. Their gearing lets them help the rider sustain maybe 18 mph or so, but they have virtually no torque at lower speeds, so they’re useless for any sort of hauling. I couldn’t just stick a bicycle trailer behind one and expect to get up the local hills, pedalling or no pedalling.

My project is to specify and acquire an electric bike that overcomes those limitations. A bike that is useful for hauling a considerable cargo and tackling the hills in my county with ease. A bike that I could reasonably use in lieu of my van for most local trips.

No such bike exists on the market in the US. But the components do exist. So last summer, I hooked up with a small, progressive bicycle shop in North Carolina (Cycle 9) and began figuring out how we might do it. Here’s what we eventually came up with.

Frame

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Surly Corporation’s Big Dummy ). This is an extended frame intended for hauling cargo, made in the US. Surly isn’t making a lot of these yet; most buyers have to wait a few months to get their hands on one. The frame is designed to carry a 200 lb rider and over 200 lbs of cargo.
(Photo from Surly’s web site)

Panniers

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Xtracycle‘s FreeLoaders. These are extra-large American-made panniers with an integrated rear deck which can swallow a whole lot of groceries. The Big Dummy frame was specifically designed to work with Xtracycle’s oversized accessories.(Photo from Xtracycle’s web site)

Battery

LifeBatt’s 20 amp-hour, 48-volt LiFePO4 battery. This very large battery from Taiwan (nearly 40 lbs) will be mounted on the Freeloader’s rear deck, leaving the panniers free for cargo.

Propulsion

Two hub-mounted 400-watt electric motors manufactured by BMC. These motors are internally geared to deliver better torque at low speed than most other motors on the market. The motors will both be controlled by a single grip throttle. They’re made in India.

Trailer

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A Cycletote lightweight aluminum cage trailer, with a custom hitch mount fabricated by Cycletote for the Freeloader’s rear stays. This American-made trailer can haul up to 150 lbs or so, with only a fraction of that weight landing on the bicycle frame. Unlike some bicycle trailers, this one attaches at the bike’s center, and so doesn’t pull the bike sideways as you ride. (Photo from Cycletote’s web site. The Rubbermaid box shown on the trailer is sold separately.)

Additional Notes

There are a lot of other details involved, of course. The Big Dummy is sold as a frame, not a complete bicycle, so we’ve had to build the bike up from scratch, using components from all over the world.

Note: The obscurity of some of the manufacturers involved is extreme. BMC has no web site. They employ a single individual to manage all of their North American operations. The battery vendor we chose (in Taiwan) takes orders in English and ships anywhere in the world, but has no American operations and an international web site that is confusing. You really have to know what you want before you talk to them.

Cycle 9, my builder in North Carolina, has sold electric bikes before, but nothing aimed quite so specifically at cargo-hauling and low-speed torque over hilly terrain. A lot of person-hours went into researching components and working around glitches that they could never recoup from the sale of a single bike. Hopefully, they’ll be able to produce more bikes like this one, now that they know where the sand traps lie.

I expect to take delivery of the finished bike in January. I have no idea what its range will be or how much cargo it will haul up hills of varying slopes. I’ll find out.

Electrifying a bike is easy compared to electrifying a car, and it just makes sense to me to want to set up an electric bike so it can do some hauling over short distances. We’re accustomed to using our cars for hauling, but a bike like this one should be an able substitute for local trips. Electric cargo bikes have the potential to become ubiquitous.

And that could make a very large difference in our lifestyles. Less pollution, more exercise, more fun. That would be a very good thing for America.

I’ll post more about Terence’s bike once he has put some miles on it.

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If you have a project that makes a difference, let me know about it — dale at oreilly dot com, and I’ll share it on a future Remake.

Dale Dougherty

I’m founder of MAKE magazine and creator of Maker Faire. I am CEO of Maker Media, the company that produces MAKE, Maker Faire and Maker Shed. I am Chairman of the Maker Education Initiative (www.makered.org).


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