Electric Bikes
What is an E-Bike Controller?
The small computer that decides how much power the motor gets.
Simplified schematic — not to scale.
In plain English
The controller is the brain of the system, sitting between the battery, motor and sensors, deciding exactly how much power to send based on your assist level and pedalling.
A simple analogy
“If the battery is the fuel tank and the motor is the engine, the controller is the driver deciding how hard to press the accelerator.”
How it works
It reads inputs from the torque or cadence sensor, checks your chosen assist level on the display, and sends a precisely calculated amount of current to the motor.
Signs of trouble
- ⚠Erratic or jerky power delivery
- ⚠System won't power on at all
- ⚠Error codes referencing the controller specifically
Rough UK cost
£80 – £350 to replace
Always get a written quote. Prices vary by bike, region and parts brand.
Heads up: Bikeautonomy is for general guidance only. If your bike is behaving oddly or you're not confident, get it looked at by a qualified bike mechanic.