A e-bike hub motor is an electric motor integrated directly into the wheel hub of an e-bike. Instead of using a chain or belt to transfer power, the motor directly drives the wheel itself. This design makes the system simple, highly efficient, and extremely durable.
E-bike Hub motors are commonly used in:
Electric bicycles (e-city,e-MTB,E-Touring,e-grave,e-road bikes,e-urban,e-fat,e-cargo,e-folding)
Electric scooters
Electric tricycles and delivery vehicles
Light electric motorcycles for teenager

Most e-bike hub motors today are BLDC—Brushless Direct Current Motors.
Here is how they work:

Step 1 – Battery sends power to the controller
The controller regulates the current and determines when each phase should be energized.

Step 2 – The stator coils generate a rotating magnetic field
When current flows through the copper windings, it creates an electromagnetic field.

Step 3 – Permanent magnets on the rotor are pulled by the rotating field
The rotor uses strong neodymium magnets (N-S poles arranged around the shell).

Step 4 – The rotor spins → The wheel spins → The e-bike moves forward
In short:Electricity → Rotating magnetic field → Magnet rotation → Wheel rotation
Because there are no brushes, hub motors:
Run quietly
Require little to no maintenance
Have higher efficiency than brushed motors

There are two main categories: CZJB IH/75/90/105/110/121/135 series geared hub motors and 205 series direct drive hub motors.

Geared Hub Motor (Planetary Gear Motor)
This type uses planetary gears inside the motor to increase torque.
Advantages:
Higher torque for climbing hills
Compact and lightweight
More efficient at low/medium speeds
Very suitable for city bikes and cargo bikes

Disadvantages
Has internal gears (nylon or steel), which may wear over time
Slight noise from gears

Ideal for:250W–750W e-bikes, commuter bikes, city e-bikes, delivery bikes.

Direct Drive Hub Motor (Gearless Hub Motor)
Direct drive motors do not use gears. The rotor is directly connected to the wheel shell.
Advantages:
Extremely quiet
Long lifespan (no gear wear)
Suitable for high power (1000W–3000W)
Better for speed cruising

Different countries have different regulations, and riders have different needs.
4.1 250W Hub Motor (EU Standard EN15194)
Legal in EU
Lightweight, quiet
Suitable for flat city commuting

4.2 350W–500W Hub Motor
The most popular in North America and Asia
Better torque for daily use

4.3 750W Hub Motor (USA Class 3 E-Bikes)
Powerful acceleration
Powerful acceleration

4.4 CZJB-205 1000W–3000W Hub Motor

For off-road, cargo, and electric motorbike applications

5.1 Torque (Nm)
Torque determines climbing ability and acceleration.
Higher Nm = stronger hill climbing.

Typical torque ranges:
35–45 Nm → City bikes
50–65 Nm → Commuter / mid-level
70–90+ Nm → Cargo, hills, delivery

5.2 Efficiency (%)
A highly efficient motor gives:
Longer battery range
Lower heat generation
Better long-term durability
Good hub motors usually reach 80%–88% efficiency.

5.3 Waterproof Rating
CZJB E-BIKE MOTOR use IP65: Strong water protection; suitable for rain

Hub motors dominate the e-bike market because they offer:
Low cost and high reliability
Quiet and smooth operation
Easy installation and maintenance
Compatible with single-speed and multi-speed bikes
Best choice for mass production and OEM projects

Hub motors remain the most efficient, most stable, and most economical drive system for electric bicycles. If you are building or buying an e-bike for:
Daily commuting
Urban riding
Delivery and logistics
Light cargo
Consumer products……a hub motor is the best choice.

For extreme off-road or high-end pedelec systems, mid-drive motors may offer higher performance—but at a much higher price.