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A User’s Guide for e-Assist Bikes

Dave Cohen on his Yuba Mundo cargo bike allowing him to ride with a watermelon and other goods. Courtesy photo.

David Cohen

Albert Einstein once commented, “I fear the day that technology will surpass human interaction.” The bicycle, with its inherent human physical and sensory engagement, may have been what Einstein contemplated as a model solution to foil the technological takeover of our humanity.

From the early days of penny-farthings to the modern cargo bike, the bicycle has fundamentally been linked with human interaction. This holds true even as electric-bike technology is redefining the bike, and as the e-bike is bringing about a global transportation revolution.

So, how does e-assist work? Any e-bike system includes some type of small motor that is activated on demand to assist a rider’s pedaling action. The motor may be situated either on the front hub, rear hub or in the middle, also known as a mid-drive motor that runs the front chainwheel. You’ll find endless opinions on which is best, but that really depends on what you will be doing with your bike.

The vast majority of e-bikes bought online or in stores feature either rear-hub or mid-drive motors because of the superior traction of rear-wheel drive. Mid-drive motors and their drive systems tend to be more efficient and produce more torque, because they can utilize the chain drive and rear gears. Rear-hub motors are less expensive and can be lighter. They also seem to get better and more efficient each year.

Other components of an e-bike system consist of a battery pack, a controller (the brains of the bike, so to say), and a control pad control or a throttle to adjust the level of assist. Some e-bikes include both a control pad and throttle. Most mid-quality e-bike systems feature a LCD display to indicate the level of assist power selected as well as a speedometer, odometer and a range of other information.

Owners of earlier generation e-bikes from just a few years back might be shocked at the technological strides made in a short period of time. Lightweight and reliable battery technology has certainly been a major advancement. However, with companies such as Bosch and Shimano entering the mid-drive assist scene, motor technology is keeping up. High quality e-bike motors now have cadence and torque sensors to help adjust the level of assistance based on how a rider is pedaling. Yes, there’s a lot of technology here, but there’s also an amazingly seamless and graceful feel.

Another major shift has been the dependability and effectiveness of conversion kits. A conversion kit can transform an existing bike into an e-bike and is oftentimes a cost-effective solution to purchasing an e-bike. Front-hub motor kits are generally easiest to install, but they lack traction in poor conditions. One of the most popular products currently is the Bafang mid-drive kit. It will fit virtually any bike, it’s fairly simple to install and is easily programmed. Due to their outstanding torque, Bafang mid-drive kits are a particularly common solution for cargo bikes.

What might one expect to pay for an e-bike? That really depends on where you are looking and what you need. Purchasing a basic commuter style e-bike from a retail store, you might expect to start at around $1800. That will get you a rear hub motor model with fairly low-end but adequate components. Large companies like Raleigh and smaller ones like Surface 604 have offerings like this. You’ll also find bikes online that start at $1600 on sites like, but when going lower than that, you really need to critique the quality of battery cells used and many other factors. Bikes with mid-drive motors tend to start at around $2400, but after that the sky’s the limit. What is really cool is that many budget e-bikes are now sold complete with racks, fenders, puncture-resistant tires, bells and lighting systems that run through the main battery. You just get on it and ride.

Perhaps the biggest story is the evolution of the electric cargo bike. Companies such as Xtracycle, Yuba, Tern, Madsen, Larry vs Harry, Urban Arrow and Riese and Muller are producing e-cargo bikes that can replace a car or van, many with modular options for families to transport the kids as well as for commercial applications for businesses. Almost all now incorporate built-in mid-drive technology for its superior torque capability. In the U.S., businesses like UPS are experimenting with e-cargo bikes for deliveries, and there’s even a new documentary called Motherload, exploring the e-cargo bike mobility revolution for moms and dads. Additionally, in Europe and in Britain, there are substantial government subsidies, rebates and grant programs to help replace vans and trucks with e-cargo bikes.

The number of mid-quality to really good e-bikes and e-cargo bikes on the market is certainly astounding, but it is important to point out the presence of plenty of subpar to dreadful e-bikes and conversion kits sold online or at stores like Walmart. Counterfeit battery cells, poor e-assist systems and bikes that weren’t designed as e-bikes are all out there for the taking! For a great source of information on what to consider and what to avoid, check out

The emergence of the e-bike demonstrates how technology can evolve while maintaining our core capacities to interact with the world. Combining human energy with the supplementary electric power not only positions the e-bike as the ultimate hybrid vehicle, but it also opens the door for bike transportation to be far more inclusive for seniors, families and many others and not just something for the young and fit.

As bike mobility is now regarded as an indicator species for the health of any community, the rise of the electric bike likely would have received a nod of appreciation from Albert Einstein.

Dave Cohen is an integrative psychotherapist in Brattleboro, (, specializing in approaches in mind/body modalities and ecopsychology. He is also the founder and director of VBike (, an advocacy group dedicated to promoting new bike design and technologies for everyday bicycle transportation in Vermont.

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