(New York, NY)
A rear hub motor
Whether you're purchasing your very first electric bicycle, or adding another to your collection, you'll always have a number of decisions to make when you're picking out your bike. Some are purely aesthetic considerations: which color do you want, or what sort of accessories will it have? Others are more practical, such as whether it's a step through or cross-bar frame.
Then there's a decision that some people might not even know about – what sort of motor do you want for your electric bicycle: mid-drive or hub? While some may take this decision for granted, and think "an electric bike is an electric bike," choosing the right setup can make a world of difference when it comes to affordability, ease of use, riding comfort, power, and more.
While there are a number of differences between select electric bike motors, there are some things that are going to be constant. Motor power is measured in watts. The more wattage, the more power you're going to get, making it easier to climb hills and zip along trails. Most bike brands will usually offer motors in the 200 to 600 watt range, with low end models occasionally offering even less power, and very high performance bicycles occasionally offering even more juice.
High wattage bikes will of course tend to eat up your battery life a lot faster, so those sort of bikes are usually accompanied by a larger battery, offering you more capacity for longer bike riding adventures. But the truth is, you'll likely get these different wattage options no matter which type of ebike motor you choose. And so that real motor question is, do you want a "hub" motor or a "mid-drive" motor?
The classic electric bicycle setup is powered by a rear hub motor. This method goes back as far as the late 1800s when electric bicycles were first invented, and is thus the most widely available option, standard to almost any ebike brand. As such, they are "tried and true," making them the most affordable option, as well as the one that most bike shops will be familiar with, should a traditional bike salesperson be advising you on your choices.
As it attached to the back wheel, the rider will feel the sensation of being "pushed," as the motor propels the bicycle by spinning the rear tire.
A newer variant on the hub motor is the front hub setup. This essentially swaps out your lead wheel, which is not hooked into your gearing and drivetrain, with a self contained motor and battery system. Because this setup is so self contained, it has led to some interesting new developments in recent years, such as electric "smart wheels" that let you convert a pre-existing bicycle into an electric bike.
Not only does this let you be "green" by using an existing bicycle, it also saves you some green, as these conversion kits offer good value for the amount of power they're delivering. While some brands, like the stylish Copenhagen Wheel are still in the process of bringing their offerings to the market, others like EVELO offer front hub conversion kits that start at just over $1000.
If hub motors are the economical option, think of mid-drive motors as the "upgraded" option. Yes, you'll be paying a bit extra, but you'll be getting a lot more for that money. Instead of being "pushed" or "pulled," the motor is in the middle of the bicycle, giving you a neutral ride with a lower center of gravity. This gives you more stable handling, which most riders prefer.
Additionally, the mid-drive takes better advantage of your bike's components, as the motor drives the crank, as opposed to the wheel itself. This lets the motor use any of your bike's gears, offering the rider more torque and increased performance.
While not every brand's offerings with be equal, top manufacturers' mid-drive motors should also offer easy maintenance and repairs. Simply slip out a bolt or two and you, or almost any bike shop, can easily perform troubleshooting or repairs. A rear wheel hub, on the other hand, can complicate even simple tasks like changing a flat.
Suffice to say, different motors will be good for different riders. A front wheel conversion kit is great for those that already have a great bike frame that they'd like to enhance with an electric boost, while keeping the convenience of being able to swap and repair tires easily. Plus, you get an "all wheel drive" setup, where the motor pulls from the front wheel, while your legs power the back.
Starting from scratch and sticking to a tight budget? Then rear wheel hubs are perfect for you, as you'll have a broad selection of entry level ebikes to choose from. There are of course, some trade offs: trickier riding down hills & on curves and more cumbersome setup for repairs.
Those looking for the smoothest and strongest ride should choose a mid-drive bicycle, as they not only give you a more balanced center of gravity, but they work with your bike's gearing system for optimal performance. And while they may be a tiny bit more expensive, the cost differential has really dropped as leading manufacturers have dramatically lowered their prices.