Comparison
Torque sensor vs cadence sensor
Published
Note: This page contains affiliate links. If you buy through them we may earn a commission at no extra cost to you. Learn more
In short
A cadence sensor switches the motor on when it detects the pedals turning and gives a set level of help for each assist mode, however hard you push. A torque sensor measures how hard you press on the pedals and matches the motor's help to your effort. Torque sensors feel smoother and more natural, especially at junctions and on hills, and often use battery more efficiently. Cadence sensors are simpler, cheaper and give easy help even with light pedalling.
Products for this job
Compare all 5 productsCarpat GB1: EN 15194 certified, Shimano hydraulics
Check price on AmazonAffiliate linkSAMEBIKE XD26-II: 672 Wh, hydraulic brakes
Check price on AmazonAffiliate linkSAMEBIKE RS-A01MEN: 540 Wh, 50 Nm, 27.5 in
Check price on AmazonAffiliate link
Our verdict
Choose a torque sensor if you ride in traffic, tackle hills or want assistance that feels like your own legs, and accept a higher cost. Choose a cadence sensor if you want maximum help for minimal effort on gentle routes at a lower price.
Two e-bikes with the same 250 W motor can feel completely different, and the pedal sensor is usually why. It decides when the motor starts, how much it helps and when it stops. If you have ridden an e-bike that surged at a junction or felt like it was pushing you along regardless of your effort, you have felt a cadence sensor. This guide explains how each type works, how they compare in daily riding and which suits your journeys.
How a cadence sensor works
A cadence sensor is usually a ring of small magnets on the crank axle with a sensor beside it. When the magnets start passing the sensor, the controller knows you are pedalling and switches the motor on. The amount of help is set by the assist level you choose on the display, not by how hard you push.
The result is easy, steady help. You can pedal lightly and still get a lot of assistance. The downsides are a small delay as you start pedalling, a slight run-on after you stop and a feeling of being carried rather than helped. In tight spaces, a sudden surge can be awkward until you get used to it.
How a torque sensor works
A torque sensor measures the force you put through the pedals, often in the bottom bracket or rear axle area. The controller then adds help in proportion to that force. Push gently and you get gentle help; push hard on a hill and the motor responds with more.
This feels like having stronger legs. Starts are smoother, the motor eases off as you ease off, and the bike is easier to control at walking speed. Many mid-drive e-bikes use torque sensors, and they are increasingly common on hub motor bikes too. Our hub motor vs mid-drive guide covers the motor side.
Side-by-side comparison
These are typical differences. The tuning of the controller matters too, so two bikes with the same sensor type can still feel different.
| Factor | Cadence sensor | Torque sensor |
|---|---|---|
| What it measures | Whether the pedals are turning | How hard you press the pedals |
| Feel | On or off, set help per level | Proportional, like stronger legs |
| Pulling away at junctions | Short delay, then a push | Immediate and smooth |
| Steep hills | Fixed help per level | More help as you push harder |
| Effort needed | Very little | Some effort always needed |
| Battery use | Can use more at high levels | Often more efficient |
| Cost and complexity | Simple and cheap | Costs more |
| Common on | Budget bikes and many kits | Mid-drives and better hub bikes |
Junctions, traffic and control
The difference is clearest in town. With a cadence sensor, the motor may keep pushing for a moment after you stop pedalling, and start with a jolt when you begin again. Brake levers with motor cut-off switches help, and most e-bikes have them. With a torque sensor, the bike responds as your legs do, which makes slow manoeuvres and filtering easier.
If you ride in busy traffic, or are new to e-bikes, a torque sensor is usually easier to live with. Starting in a low gear helps with either type, as our how to ride an electric bike guide explains.
Hills, exercise and range
On a long climb, a cadence sensor gives the same help whether you are spinning gently or pushing hard, so it can feel like it runs out on steep sections unless you raise the assist level. A torque sensor boosts help when you push harder, which makes steep climbs feel more natural.
For exercise, a torque sensor rewards effort, while a cadence sensor lets you take it easy. For range, a torque sensor often uses less battery because it does not give full help when you are barely trying, but assist level and terrain matter more. See our e-bike range explained guide.
Legal position is the same
Both sensor types are pedal-assist systems, so either can be used on a UK EAPC with a 250 W continuous rated motor and assistance that cuts out at 15.5 mph. Neither changes the legal limits. See UK e-bike law explained for the full rules.
When shopping, check the listing or spec sheet for the sensor type. If it does not say, it is often a cadence sensor. Our electric hybrid bikes guide lists the motor and assist details stated for each bike.
Frequently asked questions
Is a torque sensor worth paying more for? For most commuters and hilly routes, yes, because it feels smoother and more controlled. For gentle leisure rides, a cadence sensor is fine.
Can I change a cadence sensor to a torque sensor? Sometimes on conversion kits, if the controller supports it. On factory bikes it is rarely practical.
Does a cadence sensor mean I do not have to pedal hard? Yes. You need to turn the pedals, but light effort still brings the motor in.
Do torque sensors need calibration? Some do after fitting or repairs. Follow the maker's manual.
What you need
- Check price on AmazonAffiliate link
Carpat GB1: EN 15194, Shimano hydraulic discs