These motors are integrated into the bike’s chassis, often near the pedals, and drive the chain directly instead of a wheel. Often, the motor uses the bike’s existing gear system to multiply torque and give you a mechanical edge. But what are the advantages and disadvantages of this architecture?
For one, it is much more energy efficient. Whether it is a steep hill or uneven terrain, the gears drop easily, and the motor stays at its optimal RPM. Conversely, in traditional rear-hub motors, a gear shift and speed drop immediately mean a lapse in the motor’s RPM.
Secondly, by placing the motor, which is the heaviest component, right in the center of the frame, the bike’s center of gravity is far more even. Since neither wheel is heavily modified to fit a motor, fixing a flat tire is as easy as on a pedal bike.
To see how this type of architecture adapts to different riding styles, we picked a bike in four distinct categories to see how they stack up against their rear-hub counterparts.
Ride1Up Prodigy V2
Priced at $1295, the Ride1Up Prodigy V2 is our pick for a mid-drive commuter. It features a 250W motor that can generate 100 Nm of torque. The 504Wh battery can get you up to 50 miles per charge. It features a 9-speed drivetrain and hydraulic disc brakes. The frame-integrated controller keeps the aesthetic clean, while the mid-motor delivers punchy acceleration that effortlessly handles city traffic and rolling hills without breaking a sweat.
Aventon Ramblas
Priced at $2899, the Aventon Ramblas is a hardtail high-performance off-road from one of the country’s most beloved e-bike makers. It features a 250W A100 mid-drive motor with a 708Wh battery that delivers 80 miles of range. It pairs a muscular 100 Nm motor with a wide-range 12-speed SRAM Eagle drivetrain and a plush RockShox suspension fork. Unique touches include an integrated dropper seatpost for quick saddle adjustments on descents, grippy Maxxis Rekon tires, and smart software features like Uphill Start Assist and an automatic power mode.
Trek Fetch+ 4
Priced at $5000, the Trek Fetch+ 4 features a flagship Bosch CargoLine 250W mid-drive motor. It is paired with a 750Wh battery that can deliver an estimated 86 miles per full charge. It uses a maintenance-free Gates CDX Carbon Belt Drive paired with an Enviolo Heavy Duty Continuously Variable Transmission (CVT), letting you shift smoothly under heavy loads without worrying about dropped chains or wear. This bike features a 230-liter front foam cargo box with two comfortable child seats (complete with 5-point harnesses), a dual-pivot center kickstand for easy loading, and a smart cable-steering set-up that delivers nimble control despite its massive size.
Gazelle Arroyo C8
Priced at $3499, the Gazelle Arroyo C8 Elite features a 250W mid-drive Bosch Active Line Plus motor that can pump out 50Nm of torque. The bike’s 500Wh battery delivers up to 70 miles of range per charge. Instead of a messy external derailleur, it utilizes an internal Shimano Nexus 8-speed hub drivetrain encased in a fully enclosed chain guard, letting you change gears smoothly even while stopped at a red light. Ride comfort is prioritized with a headtube suspension fork and a suspension seatpost that soak up city potholes and cobblestones.
Where Does That Leave You?
All of that being said, perfection is a myth, and mid-drive systems have their faults. Because they turn the chain instead of the wheels, mid-drive systems wear out much faster. They are also noticeably more expensive because of their complex construction. Finally, because of their placement, most mid-drives won’t start with just a throttle button. Pedaling is required to start, even if the bike is a class-3 vehicle.
