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How Do Electric Bike Brakes Work?

Mountain bike rear wheel with brake.

The brakes on an electric bike are extremely vital to its operation. The braking system is activated by a lever attached to the handlebar. After the rider pulls this lever, the cable applies pressure to the pistons of the brake caliper. The pistons then push the brake pad into the brake rotor where friction is then created. This friction is the force needed to stop the bike.

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E-bikes are a common sight. A New York Times report stated that from 2019 to 2020, the pandemic bike boom raised the sales of electric bicycles by 145 percent. That’s more than twice the rate of traditional bicycles. Braking is of serious concern though.

After all, no matter how fast you go, you’re going to have to come to a stop at some point and the brakes are the tool of the trade. There are different types of braking systems used on an electric bike. Today we’ll delve into the braking system of an electric bike, how it works and what makes brakes so vital.

How Do Brakes Work on an Electric Bike?

A woman taking a brake with her electric bike.

If you’re looking to buy an electric bike, that’s awesome, but you may have many questions. You might be curious about how fast they are, how far they can go, or how the braking system works. At least that’s all the things I wanted to know when I got my first e-bike. We’re going to focus on the brakes in this post.

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The braking system of an electric bike isn’t very complex, and it is composed of the rotor, lever, caliper, and cable. Similar to a traditional bike, the lever is the only part you interact with inside the braking system. 

After pulling the brake lever, pressure is applied to the caliper’s pistons through the use of the cable system. The pistons, which are attached to the calipers, then apply force to the brake pad, which then pushes down on the brake rotors. 

The friction created by this force creates a stopping force which helps to stop the bike. The harder you pull on the brake lever means more force is applied to the brake pad, which may help you stop quicker. However, a major drawback to this is the heat created by this friction. 

Components of the Braking System


Rubber handle of a bike with brake.

Brake levers are a vital part of the braking system. This is the device used to activate the entire system. They are attached to the handlebar on both sides, with the left brake lever controlling the front wheel and the right brake lever controlling the rear brake. 

While this is standard, some countries have different standards for which lever should control each side. Depending on the electric bike you get, the pressure may be adjusted. 


You may be wondering how the lever connects to the caliper, and no, it isn’t magic. The cable connects the lever to the caliper and runs down from the handlebar. 

A majority of electric bikes utilize the mechanical disc brake system, so this means the cables are filled with air. The benefit of this system is the lower cost of repair and upkeep. We will review the different types of brake systems and their benefits further on. 

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The caliper houses both the brake pad and pistons on the brake system. After pulling the lever, the pistons are moved and its job then is to push the brake pad into the rotor. 

The main job of the brake pad is to then apply friction to the rotor. Since this friction creates heat, the brake pad also has to absorb this heat. Due to this, brake pads usually have to be replaced first. 


This is perhaps the most visible part of the brake system. The brake rotor is the metal disc that’s housed in the wheel hub. When the brake pad gets squeezed onto the rotor, that slows the bike down by creating friction. 

How fast you slow down is dependent on how much pressure you apply to the lever. 

Larger brake rotors can slow your bike down faster, but this means more friction is created. 

The more friction your brakes create, it leads to more heat also being created, which can make your brake’s lifespan shortened. The average size for the size of rotors on an electric bike is 160 mm to 180 mm.

Why are Brakes Important on an Electric Bike?

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Brakes are a quintessential part of an electric bike. This gives the rider more control over when they want to stop the bike. They are very useful if you run into obstacles or just ride down a hill. 

The most important thing is to have a great set of brakes that gives you the shortest stopping distance possible. The faster your electric bike travels, it means the more braking power your bike will require. 

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If you notice your brakes require more effort to stop at the same distance, that usually means they need maintenance. Without the proper brakes, you could seriously injure yourself or other people by not being able to stop on time. 

Maintaining Your Brakes

Clean the rotor

A filthy, broken, or otherwise gunked-up braking rotor is among the most prevalent brake failure reasons. Rocks, dirt, sticks, and other debris may be very simple to get caught up in and lock up your electric bike, based on the design of our bike.

Bike rotor cleaning is simple because all you need is a damp towel or washcloth to run across the entire rotor disc. Remove any significant dirt from the rotor and wipe it down a few times to make sure nothing is preventing the brake pad from pushing on the rotor.

Note: If your rotor has any substantial fractures, gouges, or missing components, we strongly advise you to replace them right away.

Make Sure Your Bolts are Tight

A woman fixing her bike brake.

The brake system of an electric bike is usually held together with bolts and screws. A loose screw is typically indicated by a loud clanging noise.

However, this isn’t always the case, so it’s always great to check before each ride. If a bolt were to come off completely, it could lead to your brakes not working as they should. 

Is Your Brake Pad Oily?

If the rotor is clean, the other most likely cause of poor braking is an oily braking pad. The brake pad is directly connected to the brake rotor. Depending on what you’ve been riding through, it may become quite dusty, oily, or damp.

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When you lift the brake lever, the slicker and oilier your braking pad becomes, the more slippery it becomes, and the less friction it applies to the brake rotor. 

Brake pads should usually be cleaned with brake pad-specific chemicals or isopropyl alcohol. Other cleansers may exacerbate the condition, causing the brake pad to become even more greasy or even degrade and fall apart.

Mechanical Brakes vs Hydraulic Brakes

A man fixing a mechanical brake of a bike.

Mechanical disc brakes, both the brakes and the bikes that come with them, are often less expensive than hydraulic disc brakes. Although either type of disc brake can be installed on a disc brake-compatible electric bike, the operation is time-consuming.

It is also costly because hydraulic disc brakes require hydraulic-specific levers. If fitted to a bike with internal routing, it will need hose cutting and bleeding.

Mechanical disc brakes are much easier to use because they rely on cables and don’t require any special tools, but they can be difficult to set up and are prone to wear and strain. Although both hydraulic and mechanical disc brakes surpass rim brakes, hydraulic disc brakes have higher modulation and stopping force.

Overall, hydraulic disc brakes outperform mechanical disc brakes in terms of performance and efficiency due to the lower friction caused by the lack of a mechanical cable. 

A fluid system is far more efficient than a steel cable, which is more susceptible to wear, especially when exposed to the elements. During hundreds of miles of off-road riding, mud and grit may easily get into mechanical disc brake systems even without a cut or hole in the housing.

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When choosing an electric bike, most people chose one with mechanical disc brakes, because it’s cheaper and much easier to maintain. They are also much easier to find as it has become fairly standard. 

At the end of the day, the choice is yours and if you are willing to pay the extra price for the added benefit of a hydraulic brake system, it is important to know the benefits as well as the cost of ownership.