Braking performance is a crucial aspect of e-bikes that directly impacts rider safety. With high weights and faster average speeds, e-bikes demand powerful and reliable braking systems.
As an e-bike owner, you should know about the different types of brakes, how they work, and how to identify when they need maintenance. In addition, learning how and when to brake will help you stay safe.
In this article, we will explain why powerful and reliable brakes are essential, discuss the different features, and explain which are the best brakes for e-bikes. We will also provide tips on brake maintenance and braking technique, so keep reading to learn all you need to know.
Why Is Braking Performance So Important for E-Bikes?
Having appropriate, well-maintained brakes on your e-bike is vital for staying safe on the road or trail.
Electric bikes have heavier, reinforced frames, as well as motors, batteries, and other electrical components, meaning they often weigh double what traditional bikes do, as we explained in our electric bike weight guide.
Similarly, e-bike riders weigh more and carry more cargo than riders of regular bikes, which puts higher demands on the braking system.
Electric bikes also travel at higher average speeds than traditional bikes (except road bikes). To illustrate, the max e-bike speed of 28 mph is roughly the average speed of a professional road bike race. The ability of an e-bike to accelerate quickly also leads to increased braking frequency compared to traditional riding, especially in urban environments.
Higher weights and speeds demand more braking power to overcome the momentum and ensure a safe stopping distance. Likewise, increased braking frequency means the components, specifically the rotors and brake pads, must be maintained and replaced more frequently.
Different types of brakes offer varying levels of control and effectiveness, making it essential to choose what’s right for your e-bike.
Most e-bikes are used in busy urban environments, so reliable and responsive brakes can make a significant difference in avoiding traffic accidents. However, electric road bikes and electric mountain bikes also need strong brakes to deal with the extra weight.
With proper e-bike brakes (and good braking technique), a rider can be confident and stop safely when necessary.
Which Brakes for E-Bikes are the Best?
In the section above, we discussed why brakes for e-bikes need to be powerful and reliable—to overcome the additional forces speed and weight put on them. But which type of brakes are best for the job?
There are two braking methods; rim and disc. The name comes from the surface used to slow the bike down.
A caliper with opposing brake pads compresses the wheel rim or rotor (disc) mounted at the wheel axle. There are several sub-types of rim brakes and two main disc configurations: hydraulic and mechanical.
Disc brakes offer more power as the braking surface is closer to the brake pad, providing greater leverage. Additionally, wet conditions barely impact disc brake performance, which can’t be said for rim brakes.
Rim brakes for e-bikes are uncommon, as they are generally too weak and ineffective in wet conditions. However, some notable models like Ride1UP’s Roadster V2 and Brompton electric bikes still use rim brakes, as the bikes are lighter and less powerful.
Best Choice: E-Bike Hydraulic Disc Brakes
Hydraulic disc brakes are considered the best type of brakes for e-bikes because they offer the most power, modulation, and reliable braking performance. They also require less maintenance, although maintenance is more challenging. Likewise, hydraulic discs are more expensive than mechanical ones.
Mechanical disc brakes are an acceptable alternative, but they are usually only seen on electric bikes under $2,000.
What’s the Difference Between Mechanical and Hydraulic Disc Brakes?
The difference between the two is how they actuate. Mechanical disc brakes use a cable to transfer the force from the brake lever to the caliper. When you pull the brake lever, the cable is tensioned, causing the caliper to squeeze the brake pads against the rotor.
In contrast, hydraulic disc brakes use hydraulic fluid to transmit the force from the brake lever to the caliper. When you squeeze the lever, it pressurizes the fluid in the master chamber located at the lever. This pressure is transferred through the brake hose to the pistons in the caliper, which closes the pads over the rotor.
Hydraulic disc brakes are superior for e-bikes compared to mechanical disc brakes due to their self-adjusting nature, consistent braking power, and less manual maintenance.
Mechanical discs require more effort to apply full braking power, so they’re not as responsive or easy to modulate (control). In addition, the cable stretches and wears over time, leading to a decrease in braking performance.
In contrast, hydraulic brakes require less effort to achieve full braking power, making them more responsive and easier to modulate.
Features to Look for in E-Bike Brakes
We’ve established that e-bike brakes should be powerful, reliable, and easy to modulate and that hydraulic disc brakes offer the best performance in these areas. However, not all disc brakes are created equal. Some are designed for heavier use.
For example, downhill mountain bike brakes must be more powerful than those for a lightweight road bike.
If you’re buying a new e-bike or upgrading the brakes on one you own, consider the following five pieces of information.
- Brand: Certain companies are known for producing reliable and durable products. Tektro/TRP, SRAM, and Magura are the most reputable brands that make e-bike brakes. NUTT and Zoom are lesser-known brands in the budget component range, which don’t have the same durability as other brands. Shimano makes high-quality brakes that aren’t e-bike specific.
- Rotor size: Larger rotors (measured in millimeters) increase braking leverage and the stopping power of an e-bike and help dissipate heat that builds up from continuous braking. Most e-bikes use 180 mm rotors, but lightweight/performance e-bikes may have smaller 160 mm rotors. The most powerful, heaviest e-bikes can have rotors measuring up to 203 mm.
- Number of pistons (2 or 4): The brake pads connect to brake pistons which deliver the force that compresses the rotor. More pistons mean extra force and braking surface, increasing stopping power and modulation. Four-piston brakes are ideal for heavy Class 3 e-bikes, fat-tire e-bikes, and gravity-style mountain bikes, but most models come with 2-piston brakes.
- Brake light activation: Urban cyclists should use every tool at their disposal to communicate intentions and stay visible to other traffic. Taillights that activate when you brake provide valuable feedback to the traffic behind you, increasing ride safety.
- Motor cutoff: When you pull the levers on an e-bike, it’s vital that the motor stops delivering power, so a motor cutoff switch is a valuable feature to look out for in electric bike brakes. Luckily, most ebikes have this feature.
Motor Cutoff Switch: Crucial Feature of E-Bike Brakes
The key feature of e-bike brakes that distinguishes them from standard brakes is the motor cutoff switch. When you pull the brake lever, this switch communicates with the controller to kill the motor immediately. Only electric bike-specific brakes have this feature.
The kill switch is particularly important on e-bikes with hub motors and cadence sensors, as there can be a slight one or two-second delay between when you stop pedaling and the motor cutting out. Likewise, e-bikes with throttles should have a cutoff switch in case the rider doesn’t release the throttle quickly enough when braking.
On a heavy Class 3 e-bike, even a split second of extra power delivery could result in a severe accident. So the faster and heavier an e-bike is, the more critical this safety feature becomes.
In general, mid-drive motors cut out and engage immediately when you stop or begin pedaling, which means the kill switch isn’t completely necessary.
Is Regenerative Braking Possible on Electric Bikes?
Regenerative braking is a method of recharging a battery by converting the kinetic energy (motion), usually lost as heat, into electrical energy. This type of braking is only possible on direct-drive hub motors, which aren’t commonly used as they are heavy and inefficient.
When you apply the brakes, the motor reverses and turns into a generator that uses the energy of the bike’s momentum to recharge the battery. However, because e-bikes don’t go very fast and aren’t very heavy, the amount of energy that can be converted is minimal. Likewise, riders typically use downhill momentum to go faster. For these reasons, regenerative braking isn’t practical for e-bikes.
In contrast, cars can harvest much more of this kinetic energy as they are heavy and travel much faster. In addition, drivers often brake when traveling downhill, which allows for further energy conversion.
Popular Brands that Make E-Bike-Specific Brakes
As mentioned above, all major brake manufacturers, except Shimano, make e-bike-specific brakes.
Tektro is a long-standing Taiwanese brand that specializes in bicycle brake systems. It has the largest selection of e-bike systems, evidenced by the number of models that use them. TRP (Tektro Race Products) is a sub-brand of Tektro for high-performance bikes.
Tektro electric bike brakes are indicated by ‘E’ followed by a number, such as ‘E530’. The higher the number, the better the brakes. ‘MD’ and ‘HD’ labels are used to distinguish between mechanical and hydraulic discs. Almost all Tektro brakes have motor cutoff switches.
Magura is a German manufacturer of motorbike and bicycle components. They take technology from the motorbike industry and apply it to e-bike systems to enhance performance. Magura has multiple systems optimized for the higher demands of e-bikes. Their products include motor cutoff switches and brake light switches for enhanced rider safety.
SRAM makes one set of electric mountain bike-specific brakes labeled called G2 RE. They have four more ‘G2’ mountain bike brake systems suitable for e-bikes but not explicitly designed for that use. SRAM brakes don’t have motor cutoff switches or brake activation switches.
NUTT and Zoom
NUTT and Zoom are small-scale brake manufacturers being used by entry-level brands like Rad Power Bikes, Ride1UP, Lectric, and Blix. Their products have minimal long-term use data, so durability and serviceability are questionable.
However, the Zoom hydraulic disc brakes found on models like the Lectric XPedition perform well in brake tests. In contrast, many Rad Power Bikes customers complain about the rapid performance loss of the NUTT brakes.
How to Take Care of Your E-Bike Hydraulic Brakes
Maintaining e-bike brakes in good working order is essential for staying safe on the road and trail. Worn-out brake rotors and pads or dirty hydraulic fluid will lead to longer stopping distances and increased risk in the event of an emergency stop.
E-bike hydraulic brakes require the least amount of maintenance of all brake types. However, when necessary fixing and maintaining them is more challenging, time-consuming, and expensive.
Here are four tips for maintaining hydraulic disc brakes, but take your bike to a mechanic if you’re not comfortable fixing them yourself.
1. Keep Them Clean and Dry
E-bike brake pads and rotors can get contaminated by spray from the road or trail. Oil contamination will render your brakes almost useless, while mud and dirt will increase the wear rate of pads and rotors.
After wet-weather rides, rinse off the brakes thoroughly with clean water and dry them afterward by wiping down the brake calipers, levers, and brake lines with a clean, dry cloth. This will prevent corrosion and ensure optimal brake functioning.
If there is oil on the rotor, you can remove the wheel and clean it with disc brake cleaner or isopropyl spirits and buff it with light sandpaper afterward. Contaminated brake pads should be replaced.
2. Regularly Check E-Bike Brake Pads
Over time, brake pads wear down and lose effectiveness, so you must check and replace them when they reach the minimum recommended thickness (typically when there is less than 1.5mm of material left).
You can also check for uneven wear (glazing) or contamination. Always replace damaged/contaminated pads to ensure safe braking performance.
3. Bleed the Brakes When Needed
Over time, air bubbles can accumulate in the fluid chamber of e-bike hydraulic brakes. This results in a ‘spongy’ feeling when you squeeze the lever. Removing the air from the brakes (bleeding) will restore performance in this situation.
Likewise, dirty hydraulic fluid leads to reduced performance, so you should change it based on the manufacturer’s recommendations. The period ranges from six months to two years.
4. Inspect Pistons, Brake Hoses, Levers, and Screws
Regular inspection of the brake pistons, hoses, levers, and screws will allow you to identify any problems that need to be addressed. This can be done every couple of months or if you notice a slight loss of brake performance.
Look for loose screws around the lever and the brake caliper and any kinks or damage to the hoses. In addition, spin the wheel and check if the rotor goes smoothly and evenly between the pistons without rubbing.
Top Tips for Correct Braking with an E-Bike
The first thing to do with a new electric bike is to get familiar with what each brake lever does (the left lever is the front brake, and the right is the rear), stopping power, sensitivity, and stability when stopping.
High-quality, well-maintained hydraulic disc brakes usually require minimal input with one finger. In contrast, cheap, poorly maintained mechanical disc brakes may require a lot of force. Braking is modulated by force, so the more you squeeze, the harder you brake.
To practice, find a quiet, open area where you can comfortably get up to speed and test braking. For example, you want to know the rough stopping distance and how the bike handles when you brake at or close to max speed.
Apply pressure evenly – The best way to brake is to apply pressure to each lever evenly and slowly, avoiding sudden changes of speed that can throw you off balance or catch the traffic or rider behind you unaware.
Brake early – As discussed above, e-bikes are heavy and travel at high speeds, so the stopping distance is greater than on traditional bikes. To balance this out and avoid emergency braking situations, begin braking earlier than you would on a regular bike.
Shift your weight back when emergency braking – Your weight will naturally be pulled forward when you brake. If you brake too hard, this can cause you to be pulled forward over the handlebars. To avoid this when emergency braking, shift your weight back, lower your chest, drop your heels, and resist with your arms
Brake before the corner – When approaching a corner, do most of your braking before you reach it. Bicycles brake extremely well when traveling in straight lines but not while turning, so braking heavily in a corner can cause you to lose traction. If you need to, very lightly apply the brakes.
Pay attention to road and trail surfaces – Traction constantly varies on off-road terrain, while roads may have wet patches, changes in surface quality, or dirt and gravel gathered in corners. Given that, try braking in higher-traction areas with minimal moisture and more compact terrain.
Ebike Brakes: Final Takeaways
Understanding and maintaining the braking system of an e-bike is crucial for rider safety. With the higher weight and average speed of e-bikes, it’s vital to have powerful, reliable brakes.
In this post, we have explored why braking performance is essential for e-bikes, the types of brakes available, their mechanisms, and maintenance requirements.
Hydraulic disc brakes emerged as the superior option due to their strength, modulation, and dependability. In order to ensure the longevity and effectiveness of these systems, regular maintenance, including cleaning, checking the brake pads, and bleeding the brakes, is necessary. Furthermore, adopting safe braking techniques can greatly enhance rider safety.
So, when you’re choosing or using an e-bike, give its brakes the attention they deserve.