Before you buy an ebike, you should learn the difference between a ‘cadence’ and ‘torque’ sensor. These sensors are what tell an ebike’s motor how much pedal assistance to provide. The sensor type is one of the most important aspects of a bike’s ride quality, so it’s unfortunately this spec often goes ignored relative to power or battery size.
For some riders, the difference between a cheaper cadence sensor and a fancier torque sensor is massive and can significantly affect ride quality. For others, torque sensors aren’t worth the premium.
Cadence sensors offer the most basic type of pedal-assist technology. They measure how quickly you are turning the pedals, often by placing a series of magnets around the crank arms.
A typical ebike might have 8-14 magnets arranged in a circle, which are used as ‘checkpoints’ for pedal rotation. When movement is detected, the sensor tells the motor to start working.
Though every ebike manufacturer will tune its bike’s power delivery differently, cadence sensor ebikes generally send specific amounts of power to the motor depending on your pedaling speed and selected pedal assist level. If you have your bike set to a low assist level, for example, the manufacturer has likely set a strict limit on how much power the motor can provide at a given cadence.
The net effect is that cadence sensor ebikes tend to feel a bit like riding with a pedal-activated on-and-off switch.
As a general rule, cheaper ebikes only come with cadence sensors. Almost anything under $1,500 will be cadence-only.
A torque sensor, on the other hand, measures how hard you are pedaling — how much force you’re applying to the pedals.
On the surface, it might seem like cadence is directly tied to effort, but not always. For example, when going up a hill, carrying heavy cargo, or starting from a stop, you’ll need more power than when cruising along a flat road. Likewise, you probably want your bike to provide less of a boost when you’re going downhill…Read more>>