A torque sensor measures how hard you press on an e-bike's pedals and matches the motor's help to that effort. A cadence sensor checks that the pedals are turning and adds a set amount of help for the assist level you pick. Neither changes the legal limit: an e-bike's motor still stops adding power at 25 km/h.
This guide explains how each e-bike sensor works, how each one feels to ride, and what to check before you buy. It's written for the rider and for anyone helping them choose.
By the Ridewave team, updated October 2026
What does a pedal assist sensor do on an e-bike?
It tells the motor that you're pedalling, so the motor knows when to help. Without a sensor, a pedal assist e-bike has no way to join in with your legs.
That matters because Australian rules are built around pedalling. Transport for NSW says legal e-bikes have motors designed to assist the rider while pedalling, and that the motor cannot replace the need to pedal (Transport for NSW e-bike rules).
There are two main ways an e-bike senses pedalling: watching whether the cranks turn (cadence) or measuring the force going through them (torque). Some systems use both.
How does a cadence sensor work?
A cadence sensor notices that the cranks are turning, then the e-bike's controller sends a set amount of power for the assist level you've chosen. A low level gives a gentle push, a higher level gives more.
Most use a ring of small magnets near the crank and a sensor beside it. Once the magnets pass the sensor, the motor starts to help. How hard you press doesn't change the help much: turning the cranks is what counts.
You can pedal lightly and still get steady help, which suits relaxed rides and carrying shopping. Some cadence systems control how much current the motor draws at each assist level, which can make the help feel steadier from one level to the next. This is called a current-based cadence sensor (CBCS).
The trade off is the start. There can be a short pause while the sensor confirms you're pedalling, then the help arrives at the level you've set. On an e-bike, that moment comes while you're finding your balance, so start in a low assist level and an easy gear.
How does a torque sensor work?
A torque sensor measures how much force your legs put through the pedals as you ride, and the e-bike's motor adds help in proportion. Press lightly and you get a little help. Press harder, such as on a hill, and you get more.
The sensor is usually built into the bottom bracket (where the cranks turn) or at the rear wheel, and it reads the tiny flex in a part as you push. Many torque systems also measure cadence, so the controller knows both how hard and how fast you're pedalling.
Because the help follows your effort, easing off on the pedals eases off the motor too, which can feel natural in traffic and on mixed paths.
The trade off is that you have to push to get help: pedalling very lightly gives very little assistance, even in a high assist level. On the plus side, the help builds with your first push, so a start from the lights can feel controlled while you find your balance.
Carrying a load changes things a little. A loaded e-bike takes more effort to get rolling, and a torque system answers that extra effort with extra help. A cadence system gives the same help whatever the load, so a lower gear does more of the work.
How do torque and cadence sensors feel to ride?
Torque feels like a stronger version of you. Cadence feels like a steady push that arrives once you start pedalling. Neither is right for every e-bike rider.
When people take their first ride at our showrooms, the thing they notice first is how smooth the pedal assist feels. That first impression is the best way to judge a sensor, because the numbers on a spec sheet can't tell you how a start from the lights will feel.
| Cadence sensor | Torque sensor | |
|---|---|---|
| What it measures | Whether the cranks are turning | How hard you press on the pedals |
| How the help arrives | A set amount for your assist level | More help as you press harder |
| Pedalling lightly | Still gives steady help | Gives only a little help |
| Moving off from a stop | Can have a short pause | Follows your first push |
| Best for | Relaxed riding, light pedalling | Riders who like the help to follow their effort |
On an e-bike, you balance in the first few metres, so a lower assist level for your first rides is a good idea with either sensor. If you'd like to take your time, a steady cadence feel may suit you. If you'd like the e-bike to respond to every push, torque may suit you better.
Which sensor suits hills, stop start riding and range?
Both can climb hills and cover a full day's riding on an e-bike. What changes is how you use the gears and the assist levels.
- Hills. A torque sensor gives more help as you press harder on the climb. With a cadence sensor, change down a gear and pick a higher assist level before the hill, so you keep the cranks turning at a comfortable pace.
- Stop start riding. With a torque sensor, ease into the first push. With a cadence sensor, be ready for the help to arrive a moment after you start pedalling.
- Range. Range depends far more on your assist level, the load, the terrain, tyre pressure and the weather than on the sensor. A torque system can use less power when you pedal gently, but a rider who keeps a cadence system in a low assist level can also go a long way.
Gears matter on either system. The Miniwave, for example, has a Shimano Altus 8 speed shifter and rear derailleur. Change down before you stop and before a climb, whichever sensor your e-bike has, and let the motor and gears share the work.
Does the sensor change how fast an e-bike can go?
No. The sensor decides when and how much the motor helps, not where the help stops. In NSW and Queensland, a legal e-bike's motor stops providing assistance above 25 km/h, and a throttle that works without pedalling is limited to 6 km/h (Transport for NSW e-bike rules, Queensland Government e-bike rules).
Rules differ by state. Check your own state in our state by state guide to e-bike laws, or go straight to the NSW rules or the Queensland rules.
How can you tell which sensor you're getting?
Ask, read the spec sheet, then ride it. Five checks work for any e-bike:
- Ask the seller to name the sensor type. Torque, cadence or both. A clear answer is a good sign.
- Don't confuse motor torque with a torque sensor. A figure in newton metres (Nm) describes the motor's turning force, not the sensor. The Miniwave's 250W rear hub motor is rated at 65 Nm, for example, and that number says nothing about how it senses your pedalling.
- Watch out for brand names. A trade name for a sensor tells you little. Ask what it measures.
- Start from a standstill on the test ride. Pedal gently, then press harder, and notice whether the help changes with your effort or stays the same.
- Try a hill or a slope. That's where the difference between the two is easiest to feel.
Which Ridewave e-bike should you try?
Let the riding you do guide the choice, then feel the assist for yourself on a test ride.
- For two wheels that fold away: the Miniwave folding e-bike. A 250W rear hub motor, a step-through folding frame and Shimano Altus 8 speed gearing, for riders who want an e-bike that folds away between rides.
If you'd rather ride on three wheels, the Ridewave Koala, Quokka, Wallaby, Wallaby Plus and Platypus e-trikes use a current-based cadence sensor (CBCS), and you can compare them in the electric trike collection.
When the sensor isn't the deciding question
If the rider can't pedal for most of the trip, no sensor changes that. Pedal assist e-bikes are made for people who want to keep pedalling, with the motor helping. And if you want to ride fast for sport, the 25 km/h limit applies whichever sensor an e-bike has.
Frequently asked questions
Can you swap a cadence sensor for a torque sensor on an e-bike?
Usually not as a simple upgrade. The sensor, the controller and the motor are set up to work together, so a swap can mean changing several parts. Ask a qualified mechanic first, and check what it means for your warranty.
Does a torque sensor mean less exercise?
Not necessarily. A torque sensor only helps as much as you push, so you stay involved in every pedal stroke. A cadence sensor lets you pedal lightly and still get help. Either way, you choose the assist level.
Do pedal assist sensors need any care?
A little. Keep the area around the cranks clean, check that cables aren't pinched or loose, and look for an error on the display. If the assist cuts in and out, book it in with a mechanic rather than taking the sensor apart.
Feel the difference in person
The difference between torque and cadence is easier to feel than to read about. A few metres from a standstill and one gentle slope will tell you which you prefer.
Test rides run at our showrooms in Vermont (Melbourne), Girraween and Marrickville (Sydney). Most visits take 30 minutes to an hour, and you're welcome to bring someone along. Call ahead so we can have the right model ready for you: book a showroom test ride, or call us on +61 468 095 888.
Sources
- E-bikes, Transport for NSW, checked October 2026
- Electric bicycle rules, Queensland Government, checked October 2026
Related articles
- E-bike motors explained: hub and mid-drive motors, and how they deliver their help.
- How fast do electric bikes go in Australia?: the 25 km/h rule and what it means on the road.
- E-bike laws in Australia, state by state: power, speed and footpath rules for every state and territory.