Just like any other bike, e-bikes rely on brakes to help you slow down and stop when you need to. The only difference is that their brakes are usually more powerful because an e-bike can go a lot faster and travel farther than regular bikes.
Pulling the brake lever on your E-Bike causes the brake pads to press down and stop your tires. Rim brakes, disk brakes, or E-brakes all operate a little differently, and you should know which kind you have. There are simple brake upgrades like E-Brake levers and kill switches you can add to your bike.
So, if you want to know how brakes work in your e-bike and how you can maintain them, we have all the information you need right here. Whether you just want to understand your bike’s brakes, or maybe you want to have a go at fixing or replacing them yourself, we’ll be going through all the details you need to know!
How Does Braking on an Electric Bike Work?
Whether you have an electric or a regular bike, the brakes function by pressing brake pads on the wheels. This contact produces resistive friction, which decelerates and eventually stops the bike.
Here is a more detailed description of how brakes work in an electric bike:
Bike brake systems contain many components like levers, cables, pistons, calipers, and brake pads. When you press a brake lever on the handlebars, it creates a compressive force in the cable, which pressurizes the piston at its end.
This piston then squeezes the brake pads against the rotor (the metal disk attached to the wheel). The friction between the pads and rotor creates resistance and slows down the wheel.
The two most common types of e-bikes braking systems are rim brakes and disk brakes. Their difference lies in where the resistive force is applied.
How Do Rim Brakes Work?
Traditional rim brakes are made of a fork or a U-shaped frame that’s looped around the wheel’s edge. Two brake pads apply friction to the rim to stop the bike.
Although rim brakes are lightweight, cheap, and easy to maintain, they come with a significant disadvantage. They are not efficient on wet, muddy roads.
How Do Disk Brakes Work?
Disk brakes are located near the center of the wheel, and they work by pressing brake pads onto a rotor attached to the hub of the wheel. Disk brakes are expensive but more efficient than rim brakes and provide immense stopping power.
There are two types of disk brakes: mechanical and hydraulic disk brakes.
Mechanical disk brakes work with a cable-actuating system. When you pull on the brake lever, it pressurizes the air in the cables and pushes the brake system’s pistons.
Hydraulic disk brakes have fluid-filled lines. With them, pulling the brake lever forces the fluid through a valve and pressurizes the caliper pistons. This system is more powerful and less affected by weather conditions than mechanical disk brakes are.
The type of brake used on your e-bike will mostly depend on personal preference, bike wheel size, and the terrain you’ll be riding on.
Electric bikes also have another unique braking system, known as e-brakes. They function by controlling the power supply to the motor, so there is no physical resistive braking force when you pull the brake levers. Instead, they cut power from the motor, and the bike slows down.
What are E-Brakes?
Electric bikes have secondary brakes called e-brakes. E-brakes rely on sensors to detect the movement of the brake levers. The sensors are set into the bike’s handlebars, and they can be mechanical or magnetic.
When you press the brake levers, it opens the sensor’s circuit and signals the e-brake controller unit to cut off power from the battery.
Mechanical sensors work like a switch. You might be able to actually hear the clicking sound it makes when you pull the lever. Magnetic sensors function in the same way but are far less detectable. Some e-bike models also come with pedal-assisted e-brakes. It depends on how the brakes are integrated into the bike’s design.
Though it is not recommended to rely on e-brakes alone, they are critical as emergency brakes. If you forget to release the throttle, or it gets locked, e-brakes can override all other mechanisms and stop your electric bike by cutting the power supply.
E-bikes with regenerative braking also employ e-brakes to engage as soon as the rider pulls on the brake lever.
E-brakes are an optional feature, and we don’t see electric bikes with dedicated e-brakes very often. Right now, they’re only found on the high-powered trail and mountain bicycles. On the other hand, mechanical or hydraulic disk brakes are compulsory for all e-bikes.
As more powerful motors are developed, we anticipate seeing more e-bikes with integrated e-brakes as a standard safety feature.
Can You Upgrade Your E-Bikes Brakes?
Yes, you can do modifications to upgrade your electric bike’s existing brakes, convert from mechanical to hydraulic brakes, or install new e-brakes if you don’t already have them. Let’s explore some options.
Upgrading From Mechanical to Hydraulic Brakes: Converting from mechanical to hydraulic brakes is neither easy nor cheap. Usually, if you want to attempt this, you’ll have to change the levers, shifters, calipers, cables, and basically every other part of the brakes.
However, there are mechanically actuated hydraulic calipers (on Amazon) that can engage with mechanical brakes and still outperform. In addition, they take just 20 minutes to install, and you’ll be able to enjoy hydraulic brakes without spending hundreds of dollars on new parts.
Install E-Brakes: E-brake levers and magnetic kill switch kits are readily accessible. If you have mechanical disk brakes or hydraulic brakes, they should be straightforward to wire up and use.
Many inexpensive kill switch systems (on Amazon) are available that can be installed in a matter of minutes. They usually include a tiny magnet, a wire with a magnetic hall sensor on one side, and a connector to the battery controller on the other side.
When you pull the lever, the magnet gets away from the sensor. This prompts a signal to the controller, which cuts off power from the bike’s main battery pack. Or you can simply replace your stock brake levers with a pre-set e-brake lever (on Amazon).
Upgrade to Larger Disc Brake Rotors: Bigger rotors (on Amazon) produce more braking power with less hand effort. Since you’ll get more surface area, it’ll also drastically reduce the heating of the brake discs, especially on long descents.
Of course, you’ll need a caliper adapter to compensate for the disk size difference. You can also upgrade to metallic pads (on Amazon), which dissipate heat better and last longer than organic pads.
How To Clean and Maintain Your E-Bike Brakes
Every bike needs attention, and e-bike brakes are no exception. If you take good care of them, they can last for years with minimal repairs. Brakes are the main safety features of your bike. If you’re having trouble braking, it’s probably time for deep cleaning.
Since each bike model has its own brake design, please refer to the manual for detailed cleaning instructions. Here we will only list the basic steps and tips for e-bike brake maintenance.
Clean and Change the Brake Pads
The brake pads are the primary wear parts of the e-bike brakes, so they need to be inspected and replaced regularly. Usually, a set of organic brake pads will last for 500-700 miles, while metallic pads can last much longer.
Water, grit, and oil can quickly damage the brake pads, so keeping them clean is important. To clean the pads, remove the brake pad shoes and use a clean cloth or paper towel soaked with alcohol solvent or brake pad-specific cleaning chemicals to wipe them down. Don’t use soap or liquid cleaners since they can initiate corrosion.
You may get away with cleaning if the pads aren’t too worn out. Otherwise, replacing them with new brake pads (on Amazon) is preferable.
Clean the Rotor
Any debris or gunk build-up in rotors is bad news and can severely damage the brake system. First, remove any sticks or leaves caught in the holes, then clean the surface with a wet cloth.
Next, use a good disk cleaner (on Amazon) to clean it thoroughly because grease and oil attract dirt and cause grime build-up between the rotor and brake pads.
If you notice bending, cracks, or warp, it’s time to replace it with a new rotor (on Amazon). Such damage can be dangerous, and you’ll be at risk of brake failure in the middle of a critical situation.
Replace Fluid in Hydraulic Brakes
If you have hydraulic brakes, the fluid can lose its lubricity after long-term exposure to heat and temperature changes, directly affecting the braking power. Low fluid levels could also lead to sudden failure, so it’s important to regularly keep an eye on it. It’s advisable to bleed and change the fluid every two years.
Brake fluid replacement kits (on Amazon) are available in the market, and they are very easy to use. Follow the instructions and fill the tubes with fresh fluid. However, if you are not confident enough, you better take it to your mechanic.
Check Cable
The brakes work in a closed circuit, and any malfunction will result in a total failure. Check the cables for any fraying or other damage. Smooth bends should be fine but not too tight.
Check at the joints and make sure everything is properly sealed. You may also replace the old cables with a new cable housing (on Amazon), if necessary.
Check Nuts and Bolts
After a while of rough riding, nuts or screws around brake assembly can come loose, especially the ones exposed to impact and vibration. They can misalign the brake shoes or, even worse, loosen the rotor. So check these nuts regularly and tighten if necessary.
Brake Alignment
Misalignment between the brake pads and rotor will cause slow brakes and potentially damage the rotor and brake calipers. Unfortunately, it usually occurs after a crash or a hard landing and can easily go unnoticed.
Depending on the type of brakes, you may only need to loose or tighten a few bolts. However, if there is any complex adjustment required, take it to your mechanic. To do it yourself:
- Open the brake caliper assembly and put two cards between the brake pads and the rotor.
- See if the cards fit snugly and parallel to the rotor. If they don’t, adjust the alignment accordingly.
- Remove cards and replace the caliper.
- Test the brakes to ensure they work properly.
That’s pretty much all you need to do for general brake maintenance. Just remember to keep an eye on the basic things, clean/replace parts when necessary, and you’ll be good to go.
Do Any Bikes Have Regenerative Braking?
Yes, The Rad City, The Stealth, the Grace Electric, and The Stromer manufacture bikes with regenerative braking.
Regenerative braking recaptures the energy from braking and stores it in the battery. This helps extend the range and reduce wear on your brake pads.
Although regen braking is a great way to recapture some energy, it’s not as efficient in electric bikes as it is in electric cars. So, except for a few manufacturers, we don’t see this feature in most electric bikes.
How Does Regenerative Braking Work on an E-Bike?
Any moving object stopped by force produces kinetic energy. Similarly, when you apply brakes to stop the wheel, lots of that energy is generated. Which either dissipates as heat or gets absorbed by brake pads and causes damage to them.
Regenerative braking is based on a simple idea. It harnesses some of that energy, converts it into electricity, and puts it back into the battery.
Electric bikes work on a motor powered by a battery. With regenerative braking installed, whenever you apply the brake, this motor converts into a generator for a few moments and produces electricity out of the braking force, and stores it back into the battery.
This system is not perfect for bikes, as the total energy produced is not much, and some energy is always lost as heat, but it does help extend the bike’s range.
Electric bikes are becoming more and more popular, and for good reasons. They’re fun to ride, easy to maintain, and environmentally friendly.
But, like any other machine, they require some basic maintenance to keep them running in top condition. We hope this article helps you better understand the brake system on electric bikes and you found our maintenance tips helpful.
If you want to learn more about electric bikes and e-brakes, visit our comprehensive blogs on e-brakes and regenerative braking.