A cadence sensor tells the motor that you are pedalling, and the motor adds a set amount of help for your assist level. A torque sensor measures how hard you press on the pedals and adds help in proportion. Cadence feels like an on-off boost that asks little of your legs; torque feels like stronger legs and gives finer control in traffic, on hills and on loose ground.
Rules mentioned here were checked October 2026 (sources at the end). This is general information, not legal advice.
How a cadence sensor works
A cadence sensor detects that the cranks are turning, commonly with a ring of magnets and a sensor near the bottom bracket. Once it registers rotation, the controller sends the motor a set share of power for the assist level you picked. Pedal lightly or hard, and the help stays about the same.
The result is an easy, predictable push. Because the sensor has to see the cranks turn, there can be a short delay before the motor engages. In tight spaces, a fixed burst of power can feel abrupt, so a low assist level helps in crowds and parking lots.
How a torque sensor works
A torque sensor measures the force you put into the pedals, commonly with a strain gauge at the bottom bracket or rear axle. The controller multiplies your effort: push harder and the motor pushes harder; ease off and it eases off. Some torque systems also read cadence.
That proportional response feels natural, like riding a regular bike with stronger legs. It gives fine control when starting on a hill, threading through traffic or riding loose gravel. The trade-off is that the motor only helps as much as you push, so a torque system asks you to keep working.
What assist levels do with each sensor
On a cadence-sensor bike, each assist level sets how much help the motor gives, or on some bikes a top speed for that level, whatever your effort. On a torque-sensor bike, each level sets a multiplier on your own effort, so the same push gets more help at a higher level. With either sensor, the motor still stops helping at the assist cut-off: 32 km/h on a legal e-bike in Ontario, Quebec and Alberta and on a B.C. standard e-bike.
Torque sensor vs cadence sensor: comparison table
| Feature | Cadence sensor | Torque sensor |
|---|---|---|
| What it measures | Whether the cranks are turning | How hard you push on the pedals |
| How help is set | By assist level, not effort | In proportion to your effort, scaled by assist level |
| Feel | On-off boost | Like stronger legs |
| Starting on a hill | Short delay, then a set push | Help arrives as you press down |
| Tight spaces and traffic | Can surge | Fine control |
| Effort | Low effort at higher assist | Your effort drives the motor |
| Parts | Simple sensor | More complex sensor |
Which one suits you
- You want help without pushing hard: a cadence sensor gives steady assistance for little effort.
- You commute in traffic or ride in groups: a torque sensor's proportional help makes your speed easier to control. Compare commuter e-bikes.
- You climb steep hills: a torque sensor responds the moment you push down, while a cadence sensor needs the cranks moving first.
- You ride trails or loose ground: proportional power helps you keep traction. See mountain e-bikes.
- You want exercise: a torque sensor rewards effort, so a harder push gets a bigger result.
- You want an easy step-on, step-off ride: pair either sensor with a step-through frame and pick the feel you prefer.
Pedal assist, throttles and the rules
Provincial rules don't name a sensor type, but they do say how assistance must start and stop. B.C. requires safety features that stop the motor when you brake, stop pedalling or release the throttle, and its light e-bike class can't have a throttle at all. Alberta's definition requires pedal assistance to stop as soon as you stop pedalling, and throttle assistance to stop when you apply the brakes.
Ontario's April 2026 proposal would make its Class 1 pedal-assist only, with walk assist up to 6 km/h; in October 2026 it was still a proposal. In Toronto today, only e-bikes that require pedalling may use protected bike lanes, and e-bikes that don't require muscular power are kept off park paths. Both sensor types are forms of pedal assist; a throttle is a separate control that a bike may or may not have.
Our e-bike laws page covers the full rules by province.
How to tell what a bike has
- Read the spec sheet for "torque sensor", "cadence sensor" or "pedal-assist sensor (PAS)". "PAS" on its own doesn't say which type.
- Look at the assist levels: how many there are and how they are described.
- Check for a throttle, and whether you need or want one where you live.
- Ask through our contact page if a listing doesn't say.
Does the sensor change range?
Not directly. Range follows battery watt-hours and how much energy each kilometre costs, which depends on assist level, speed, hills, weight and weather. Your own effort is part of the equation with either sensor, and riding gently at a low assist level stretches any battery. Our range guide shows the math.
Sensor type also interacts with the motor. A mid-drive and a hub motor can each be paired with either sensor, and our hub motor vs mid-drive guide explains how motor placement changes the feel on hills.
Frequently asked questions
Is a torque sensor better than a cadence sensor?
It depends on what you want. A torque sensor gives natural, proportional help and finer control; a cadence sensor gives steady help for little effort. Pick torque for control and a natural feel, and cadence for an easy, predictable push.
Can you feel the difference on a ride?
Yes, mostly at the start and whenever you change effort. With a cadence sensor, help arrives once the cranks turn and stays set for the assist level; with a torque sensor, it rises and falls with your push.
Do torque sensor e-bikes have throttles?
Some do. A throttle is a separate control from the pedal sensor. In B.C., light e-bikes can't have a throttle at all, while standard e-bikes may.
Does the sensor type affect whether an e-bike is legal?
The rules cap power and assisted speed and set how assistance must stop; they don't pick a sensor type. Both types are pedal assist. Check the motor rating and cut-off speed for your province.
Sources
- Government of B.C.: E-bike requirements (updated November 4, 2025)
- B.C. Reg. 64/2024, Motor Assisted Cycle (E-Bike) Regulation
- Alberta Transportation: Rules and Regulations Applying to Small Vehicles (updated November 2018)
- Environmental Registry of Ontario 026-0422 (proposal posted April 23, 2026)
- City of Toronto: Electric bicycles (updated July 30, 2026)
Next step: compare assist systems in our commuter e-bikes.