Mid Drive refers to the mounting point of the motor; on mid-drive e-bikes it's mounted directly at the bottom bracket between the pedal cranks, and connected directly to the pedaling drivetrain. This gives some awesome benefits, and mid-drive motors are generally considered better than their hub-drive counterparts, but there are still downsides to consider! Let's dive into the positives first.
The Positives: More Responsive, Great Hill Climbers
When discussing electric bike motor systems, "responsiveness" refers both to how quickly the motor responds to pedaling input, and also to how nuanced the response is. Most mid-drive motors are equipped with torque sensors which respond to the amount of pressure the rider is putting on the pedals, putting out more power when the rider is working hard. Many mid-drives have advanced PAS sensors that measure torque, cadence, and wheel speed, taking hundreds or even thousands of measurements per second and providing incredibly responsive motor output. The result feels amazing; rider and machine perfectly in sync. Mid-drive motors can also take advantage of the gears in the pedaling drivetrain. If you shift down to first gear so that pedaling is easy, that means the motor's job is easier too! This is why almost all electric mountain bikes are rocking mid-drives; they're vastly superior at hill climbing than hub motors, which are fixed in the wheel and do not interact with the pedaling drivetrain at all.
The Downsides: Cost, Wear & Tear, Knees
Whether you're buying a complete e-bike or building your own, mid-drive motors are significantly more expensive than hub motors. They're more technically complex, and typically have more advanced features, so you are getting more "bang for your buck", but not everyone needs that extra performance. Plus, mid-drive motors will cost more to maintain; at the very least you'll have to replace your chain and rear cassette more often. Remember, that fancy mid-drive is using your pedaling drivetrain to push the bike! That puts a lot of stress on the drivetrain components, and actually most mid-drives have their power limited to prevent breaking the chain. Some of the more premium mid-drives have built-in shift detection which will reduce power when shifting gears as that's when the components are most vulnerable to damage - think about how when riding a normal bike you pedal more lightly when shifting.
Something many people may not realize is that mid-drive motors can be hard on your knees. That fancy responsive torque sensor may feel great to ride on, but it requires that you put a lot more pressure on the pedals in order to get more power out of the motor. If you've got bad knees, or are recovering from a knee injury, you may not be able to push that hard, so hill climbing is going to be a bad time! This is compounded by the fact that most mid-drive systems don't include a throttle; although some manufacturers (notably Bafang) do make mid-drives that allow for a throttle, most do not. By contrast, almost all hub motor systems come standard with a throttle, and use cadence-based sensors which only require you to cycle the pedals with light pressure. If you're in the bad knees camp, it might be worth checking those out.
I never know what to expect when people switch industries to start making electric bikes. E-bikes are hot right now and everyone wants a piece of the pie! However, in the case of motorcycle racer Eric Buell, the resulting e-bikes are simply excellent. I got to test ride a prototype of the 3S in the summer of '23 and even though it was a little rough around the edges I was blown away by the quality. The 2S is the "so long range it's extreme" variant, rocking dual batteries for a whopping 2,000 watt-hours of total capacity. Combine this with the responsive and efficient mid-drive motor from VALEO and you've got an insane amount of range potential. These Class 3 e-bikes can easily cruise at 28mph, and feel safe even on congested city streets thanks to a certified motorcycle-grade loadout of lights, signals, and mirrors - rare in the US but legally required for such a powerful e-bike in Europe. Kudos to the FUELL team for keeping those high standards on both sides of the pond!
I never know what to expect when people switch industries to start making electric bikes. E-bikes are hot right now and everyone wants a piece of the pie! However, in the case of motorcycle racer Eric Buell, the resulting e-bikes are simply excellent. I got to test ride a prototype of the 3S in the summer of '23 and even though it was a little rough around the edges I was blown away by the quality. These bikes have mid-drive motors from VALEO, a French company I hadn't heard of before. I love these motors! They're incredibly powerful and their responsiveness rivals that of high-end Bosch systems; they have an "auto mode" that intelligently adjusts not only the motor power output (which is fairly common) but also automatically shifts the gears of the internal hub. It's an incredibly elegant system; just turn on the bike and ride, and never fiddle with controls. Electronics aside these are kitted out to motorcycle specifications with surprisingly bright lights and a full suite of signaling controls, plus the usual fenders and sturdy rear rack, and even a rearview mirror!