What is Pedal Assist and How Does it Work?

Pedal assist is arguably the best part of electric bikes and the thing that makes them so wonderfully convenient to use.

See a giant hill approaching and don’t think your legs can handle it? The pedal assist will get you up there.

Thinking about commuting to and from work every day but concerned about distances and your fitness? Pedal assist makes long-distance biking easier and much more doable.

It can be argued the pedal assist IS the electric bike – without it, you’re just stuck with a regular old bicycle.

This article was written for many purposes, the most important being:

1. To explain what pedal assist is.
2. What kinds of pedal assist there are.
3. How to use and get the most out of pedal assist.

We’re going to cover a whole lot more than that though by the time this article is finished.

So you’ve ever wondered what pedal assist actually is and how much it can help you on your ride, this is the place to be right now.

Let’s get to it.

What is pedal assist exactly?

First, let’s talk about what pedal assist is NOT.

Pedal assistance is not like a typical automobile or scooter in that it propels you forward without any effort on your part. The bike will not simply take off the moment at the simple flip or twist of a button or lever (unless the bike has something called a throttle).

Pedal assist, or pedelec, provides extra power when activated and ONLY works when the rider is actually pedaling. If you’re not actively using your legs and turning the pedals, the motor will remain inactive and pedal assist will not work.

Simply put, all pedal assist does is makes things easier. The additional power provided by pedal assistance reduces the amount of energy the rider needs put into pedaling themself. That means riders are able to ride further, ride faster, and handle difficult terrain, like hills, more easily.

It also means that people don’t need to be exceptionally fit to ride either. A person with average fitness riding an electric bike can ride up a hill just as quickly as someone with above-average fitness using a regular bike, if not more quickly.

How does pedal assist work?

As mentioned before, pedal assist only works when the rider is actively turning the pedals themselves. When they are not pedaling, the bike will not accelerate or maintain speed on its own, unless it also has a throttle and the rider is using that too.

When you start pedaling, you will often feel the pedal assist quite literally kick in. Depending on the level of assistance and type of sensors used, the act of pedaling will feel much easier as soon as you start doing it. Sometimes, it can feel like the bike is “pushing” you (in a certain sense), but remember it’s not actually propelling you – it’s just making pedaling that much easier.

Most pedal assist systems come with different, selectable levels of assistance. The higher the assistance level you choose, the easier pedaling becomes. Five levels is the most common amount, although bikes with as few as three and as much as seven are not unheard of.

When using the first level, you’re only going to receive a little extra help and pedaling won’t feel that much different from a normal bicycle. As you switch to higher levels, the pedal assist becomes more and more noticeable and riding becomes easier and easier.

One thing to keep in mind is that the higher the pedal assistance, the more energy the motor needs. This energy comes from the bike’s battery thus the more pedal assistance being used, the more energy is drained from the battery.

Levels of pedal assistance

Here is a very rough breakdown of what you can expect from an electric bike with five levels of pedal assistance:

• Level 1 – Very little assistance. Not too different from riding a regular bike with just a faint amount of help. Better if you want to conserve the battery and/or get a workout in with your ebike. Riders will probably be averaging less than 10 MPH on level ground.
• Level 2 – A little bit more “oomph” from the motor. This level is a nice standard for those who use their e-bike often, especially in urban areas. Not too fast and not too much energy drainage.
• Level 3 – A decent amount of assistance. You’ll want to be at this level when going up hills as the amount of effort required to climb them becomes exponentially greater. On flat terrain, riders will probably be hitting speeds of around 15 MPH.
• Level 4 – At this point, you’re really going to feel the pedal assist, so much so that it can feel like the bike is pedaling itself. Average speed will approach 20 MPH and riding up hills will become much easier.
• Level 5 – The maximum amount of assistance you can get out of your motor. Depending on your ebike, you can go really fast really quickly with this level selected. Most pedal assist systems will cut out once the bike has reached around 20 MPH. This is for legal reasons. Also, batteries will drain quite quickly.

 

Of course, all of the above varies from e-bike to e-bike and rider to rider. These are just generalizations to give you an idea of what to expect from a pedelec.

Are there different types of pedal assist?

There are several different types of pedal assist currently available on the market. Considering these types is an important decision when buying an electric bicycle.

The two main types of pedal assist are cadence sensors and torque sensors. Both have their own strengths and weaknesses.

Throttle is sometimes considered a type of pedal assistance but technically is not, seeing as one often doesn’t need to actually pedal to use the throttle. Regardless, we’ll go over what throttle is in addition to the two aforementioned sensors in the following section.

Cadence Sensor

Cadence sensors are probably the most common type of pedal assistance.

The way they work is quite straightforward: when you pedal, a magnet installed adjacent to the pedals sends a signal to the motor to activate, at which point the pedal assistance kicks in. Simple as that.

The amount of assistance provided by a cadence-based pedelec, again, depends on the level of assistance you select. Lower level = less assistance, and vice versa.

Due to the cadence sensor’s simplicity though, the system can be a bit wonky at times. Some electric bikes will jerk forward the moment the motor kicks in and switching between pedal assistance levels can be rough sometimes.

Though they can detect the rate at which you are pedaling as well, cadence systems cannot detect the force you are actually applying. If you’re riding on terrain where your rate of pedaling or the amount of force you put in changes drastically, like a hill, the sensors might get confused.

Luckily, despite their shortcomings, most cadence systems have developed to the point of being quite intuitive. They used to be really jerky in the early days but as the technology has advanced and more magnets have been added to the system, things have really smoothed out.

A lot of people prefer cadence sensors for their simplicity and for the fact that they can be controlled more directly.

Torque Sensor

Torque sensors are more advanced than cadence sensors and are relatively less common. A lot of riders claim that they offer the smoothest pedal assistance experience possible as well.

Unlike the simpler cadence varieties, torque sensors are able to sense the amount of force the rider is using when pedaling. The harder you pedal – i.e. the more force you use – the more pedal assistance the motor provides.

Torque sensors are less noticeable when active because they mirror the rider’s own output so well. Rather than shifting levels manually, a torque sensor will just know when you need more help based purely on the effort you’re putting in. Relax and the motor will back off as well.

A lot of people prefer torque sensors because they feel most similar to riding a regular bike.

That being said, others believe that they’re not any better than cadence sensors. With a cadence sensor, at least you have greater control over the amount of assistance and can set it as you want.

Ultimately, most would agree though that a system composed of both cadence and torque sensors is ideal. Such a system would offer both the control of a cadence sensor and the smoothness of a torque sensor.

What’s the difference between pedal assist and throttle?

We’ve already made the important distinction that pedal assist requires the rider to actually be pedaling in order to work.

Propulsion that doesn’t require any sort of effort from the rider is usually achieved via a throttle.

Throttles don’t require the rider to be pedaling at all in order to work. Rather, the throttle can be activated via a simple mechanism, usually a twisting grip or lever on the handlebar. When it is in use, the e-bike will propel itself, allowing you to enjoy the ride without putting any energy in yourself.

Worth noting is that, when active, the throttle will not cause the pedals themselves to turn – they will remain stationary as if not in use. The gears of the bikes will be turned by the throttle though. On some e-bikes whose gears are visible externally, you can see them actually turning on their own.

E-bike throttles are very similar to the throttles on motorized scooters and motorcycles. For this reason, they are more strictly regulated as well. Certain international regions, like the EU, don’t actually permit throttles on electric bikes at all.

To get around these bans, some e-bikes have a throttle that, like pedal assist, only works when the rider is pedaling. In this case, the throttle acts more like a “boost” rather than something that keeps it going. As soon as you stop pedaling, the throttle turns off and you lose the additional speed. So these can’t really be considered “pure” throttles.

What are the benefits of pedal assist?

We’ve already mentioned a lot of perks to having pedal assist. In truth, the pedal assist really is the best part of electric bikes and the thing that makes them so wonderfully useful.

In case you aren’t already sold on electric bikes or the pedal assist they offer, here are some more reasons to get on board:

1. With pedal assistance, hills are less challenging and more enjoyable.
2. Pedal assistance allows you to save your own energy, which means that you can ride further without getting tired.
3. You can get to and from the places you need to faster. Those who commute to work with an electric bike can really stand to benefit from this.
4. You can enjoy your rides more without having to worry so much about physical effort. If your bike has a throttle, you can really relax a bit! Just don’t become so relaxed that you lose attention and then crash.
5. More intensive bike activities, like bikepacking or bike tours, are less intimidating as the physical hurdle is bypassed. A lot of people will actually opt to travel with their electric bike if they know there are other more physically capable riders in the group so that they can keep up better.

How do I use pedal assist bikes properly?

There is definitely a certain way to ride an electric bike and get the most out of its pedal assist system. Granted, riding an electric bike is very similar to riding a regular bike, but there are some key differences that you need to be aware of.

First, you’ll want to select the appropriate riding mode or level of pedal assistance you want to use. It’s best to start lower and then work your way up the levels as you start riding. Try to avoid riding on the highest level possible at all times – this is a good way to deplete the battery more quickly.

Next, just start and continue to pedal. Find your own rhythm or “cadence” and then let your legs do the rest.

While riding, you want to avoid standing on the bike and jacking down on the pedals. This is a common habit people have on regular bikes and can really interfere with the sensors in the pedal assist. Just remain seated with your butt to the rubber and let the pedal assist do the work for you. Just increase assistance on the difficult bits.

Keep in mind that with pedal assistance activated, you can achieve high speeds much easier. It can be difficult to maneuver while going super fast, especially considering that an electric bike is also a lot heavier than a regular bike. So don’t get in over your head and ride too quickly too soon – that’s how accidents occur.

When you don’t want pedal assistance anymore, simply stop pedaling or hit the brakes. Both will cause the motor to cut out and the assistance to cease to work.

Wrapping Up

The pedal assist is arguably the most important part of an electric bicycle. Without them and the additional support they provide, an electric bicycle wouldn’t be very special at all – it’d just be a regular bike at that point.

Knowing what pedal assist is and how it can help can improve your riding experience. With the right technique and treating it right, you’ll get the most out of the system and save your bike’s battery at the same time.

For that matter, having the right kind of pedal assist – the one that you prefer to use – will only make the ride better.

Hopefully, you’ve gained a little extra knowledge by reading this article. If there’s any part of the pedal assistance that you’d like clarification on, please leave a comment below and we’ll do our best to help.