Motors & Wheels

Hub motors and complete motor wheels. Check wheel diameter, tire width and dropout spacing (135mm standard / 170mm / 190mm fat) before ordering.

How to choose a hub motor or motor wheel

Four things decide whether a hub motor or motor wheel will fit. Measure them on your own bike before ordering: a bike name in a product title is not proof of fit, the measurements are.

Rear dropout width. Take the wheel out and measure the inside distance between the two dropouts with a caliper or a ruler. Narrow-tire frames are commonly 135 mm; fat-tire frames are commonly 170 mm or 190 mm. Do not assume 170 mm and 190 mm are interchangeable: some motors can be spaced between the two, but not all can, so measure your frame rather than guess. Front forks are commonly 100 mm, and fat-tire forks are often wider, so measure the front as well.
Axle diameter. Hub motor axles are commonly 12 mm or 14 mm. Measure the axle diameter on your current motor and the slot in your dropouts; a 14 mm axle needs a dropout opening wide enough to take it.
Voltage. Battery, controller and motor must share the same nominal voltage, whether that is 36V, 48V or 52V. A 48V motor needs a 48V controller and a 48V battery. Too high a voltage can burn out the controller; too low leaves the motor weak or trips low-voltage cut-off. Check the label on your battery and controller before choosing a motor.
Wheel size and tire width. A complete motor wheel has to match your original wheel diameter (20, 24, 26, 27.5 or 29 inch, or 700c) and tire width. A 20 inch fat-tire wheel and a 20 inch narrow-tire wheel are different parts.

If any of these numbers is unknown, measure or check it first rather than ordering by bike name.

Step-by-step help: axle washers and torque arms, motor wheel or bare hub motor, why a bolt-on hub motor will not fit a thru-axle frame and how to change a hub motor. Turn the bike off and remove the battery before you unplug the motor cable.