Electric bicycles, popularly known as e-bikes, are bicycles powered by a battery and motor. These bikes are different from motorcycles - they do not use fuel. Instead, the motor helps a rider pedal easily. 

Popular in cities, e-bikes use disc brakes with a lever and disc. The lever is on the handlebar, while the disc is on the wheel. Together, the lever and disc help to slow down the bike.

It is important to note that disc brakes can either be mechanical or hydraulic. Mechanical disc brakes have a cable that connects the lever and the caliper. Hydraulic disc brakes, on the other hand, use a fluid system that connects the lever and the caliper. 

Both types of disc brakes have their pros and cons. The best choice also depends on the rider's needs and wants.

Braking is an essential and safety-critical aspect of riding an e-bike. You may be wondering which type of braking system to choose between mechanical and hydraulic.

This article explores disc brakes, how they work, the differences between mechanical and hydraulic brakes, and the best one for you.

What are the Hydraulic Disc Brakes?

Hydraulic disc brakes are disc brakes with a fluid system that uses oil or brake fluid. The main components of this system are the brake lever, the master cylinder, the hose, the caliper, the brake pads, and the disc rotor.

When you squeeze the brake lever, the fluid in the hose is pressurized and pushes the brake pads onto the disc rotor, which creates friction and slows down the wheel. 

Pros of Hydraulic Disc Brakes

Hydraulic disc brakes have many benefits. They are:

Better braking power and modulation: hydraulic disc brakes are responsive and consistent. They are easy to control and require minimal effort. This type of braking system allows you to adjust the braking force.

Self-adjusting and self-cleaning: Hydraulic disc brakes adjust for pad wear and rotor alignment. They always work well because of their self-cleaning mechanism. It also prevents dirt and debris from blocking the system.

Lighter and more compact: hydraulic disc brakes have fewer parts and less cable, which makes them lighter and more aerodynamic. This type of brake looks sleek and modern.

Heat dissipation: Hydraulic disc brakes have a compression and fluid system that prevents heat buildup when the system is in use. Because they can stay cool while in use, these types of brakes do not need frequent maintenance or replacement. 

Work well in bad weather: hydraulic brakes have high stopping power even in the rain. 

Smooth operation: Hydraulic disc brakes have a high stopping power and therefore let you ride faster and more smoothly.

Cons of Hydraulic Disc Brakes

Hydraulic disc brakes also have their downsides.

Cost: Hydraulic disc brakes are complex and used in high-performance e-bikes. Due to their complexity, these brakes require special tools for maintenance, which can be expensive. 

What are the Mechanical Disc Brakes?

Mechanical disc brakes are disc brakes with a cable. The cable is tightened by a spring, which is in the lever. This braking system has several main components, including the brake lever, the cable, the housing, the caliper, the brake pads, and the disc rotor.

When you squeeze the brake lever, the cable in the housing is tightened and pulls the brake pads onto the disc rotor, which creates friction and slows down the wheel.

Pros of Mechanical Disc Brakes

Mechanical disc brakes have some advantages. They are:

Cheaper and easier to maintain: Mechanical disc brakes cost less than hydraulic ones. They are good for cheap or casual folding e-bikes. This type of brake is also simple and easy to fix. All you need are common tools and skills.

Modulation: Although mechanical disc brakes do not provide the same level of modulation as hydraulic brakes, they still allow you to be in control of your rides. Modulation is the ability to vary the braking forces. This characteristic is particularly helpful if you do advanced cycling, such as mountain riding. 

Reliability: Mechanical disc brakes are more reliable than their hydraulic counterparts. This type of brake is less prone to failure and leakage. They can also withstand harsh weather and temperature conditions. 

Mechanical disc brakes come with their disadvantages, including;

Less stopping power: This type of disc brake offers less braking power compared to hydraulic brakes. Therefore, they will require extra effort and precision to control.  

Frequent maintenance: You will need to frequently maintain your mechanical disc brake to get the most out of it. The cable may fray, stretch, or wear and tear, requiring replacement. 

Weight: mechanical disc brakes are heavy and less compact because of the cables. This feature also makes the brake less aerodynamic and modern.

The main differences between mechanical and hydraulic disc brakes are:

Cost

Mechanical disc brakes are cheaper than hydraulic disc brakes. You may get a hydraulic disc brake for almost two to three times the cost of a mechanical brake. The reason for this lower cost is that mechanical disc brakes are generally easier to maintain compared to hydraulic disc brakes - you do not need an expert to fix your mechanical brake. 

If you are on a tight budget or do not need a bike with the additional features that come with hydraulic brakes, a bike with a mechanical brake might work just fine for you. 

In addition, it is important to note that the cheaper cost of mechanical disc brakes does not mean they are inefficient. These brakes are also highly functional and effective. 

Performance

Hydraulic disc brakes have better braking power and modulation than mechanical disc brakes. The mechanical brakes are also more likely to wear and tear due to the friction in the steel cables of the braking system. 

Nevertheless, although mechanical disc brakes do not provide as much modulation as their hydraulic counterparts, they are still functional enough for casual and commuter riders. 

So, if you do not ride your bike frequently in races or mountain bike trails, a mechanical disc brake should be efficient enough. However, if you do more advanced riding, such as mountain biking, the increased modulation of a hydraulic brake is essential.

Power and Precision

Hydraulic brakes offer exceptional power and precision compared to mechanical brakes. You can move both brake pads in a hydraulic brake. You also don’t need to engage them with a lot of force.

This means that lightly pulling on the hydraulic brake level can produce a strong braking response. 

On the other hand, you can only push one brake pad, which is not as precise as that of a hydraulic brake.

Maintenance

Mechanical disc brakes are easier to service than hydraulic disc brakes. The most common issue with mechanical disk brakes is a worn or broken cable. This type of problem is easily fixable. You can even replace the brake lines at home by yourself.

If you have a 5mm hex wrench, you should be able to fix issues that come up with your mechanical disc brake.

Hydraulic brakes, on the other hand, require higher maintenance. Only a professional will be able to fix or adjust the fluid-filled system with expertise and special tools.

However, it is important to note that hydraulic disc brakes do not require as much maintenance as mechanical disc brakes. You might have to fix your mechanical brakes frequently if you commute regularly. 

Ebikes are faster and more powerful than regular bikes and therefore need powerful brakes. In our opinion, hydraulic disc brakes are better than mechanical disc brakes for e-bikes. This is because they offer more braking power, modulation, and durability. 

In addition, hydraulic disc brakes have less cable stretch, less friction, and less noise than mechanical disc brakes, improving the performance and comfort of the e-bike. 

However, some people might prefer mechanical disc brakes because they are cheaper, simpler, and easier to maintain. They might also argue that mechanical disc brakes are good enough for casual or recreational riding and that hydraulic disc brakes are unnecessary or overkill for e-bikes.

Generally, there is no clear answer. Your choice will depend on your needs, preferences, and budget. For instance, if you prefer a bike with more braking power, safety, and comfort, a hydraulic disc brake may be the best for you. However, they cost more and require special care.

On the other hand, if simplicity, reliability, and minimal cost are your goals, mechanical brakes might be better for you. However, it is important to remember that these brakes have less braking power and modulation.

Which is Best for You?

The best disc brake for you depends on many things, such as:

Riding style and conditions

The terrain you ride matters in your choice of brakes. If you ride fast, downhill, or off-road, you need more braking power and modulation. Hydraulic disc brakes can give you that. If you ride slow, flat, or on-road, you need less braking power and modulation. Mechanical disc brakes can do that.

Budget 

If you have the money, you may like hydraulic disc brakes. They have better performance but are expensive and complex. On the other hand, if your budget is on the lower end, a mechanical disc brake might be better for you, especially if you are skilled in fixing minor brake issues. 

Personal preferences

If you want a light, sleek, and modern bike, you may prefer hydraulic disc brakes. They have fewer parts and less cable. You may prefer mechanical disc brakes if you want a heavy, classic, and customizable bike. This braking system has more parts and cable options.

What are Some Common Problems and Solutions for Disc Brakes

Here are some common problems and solutions for disc brakes on e-bikes:

Worn-down brake pads

The brake pads are the part of the brake system that contact the disc rotor to create friction and slow down the bike. If the brake pads are too worn down, they may not make proper contact or slide over the disc instead. This can reduce the braking power and cause noise. 

To fix this problem, you need to replace the brake pads with new ones. You can do this by removing the caliper bolts, pushing out the old pads, inserting the new pads, and reattaching the caliper. You can also adjust the pad position and alignment if needed.

Damaged brake lever

The brake lever is the part of the brake system that the rider squeezes to apply the brakes. If the brake lever is damaged, it may not transmit the force to the caliper properly. This can affect the braking performance and feel. 

You can fix this problem by replacing the brake lever with a new one. You can do this by disconnecting the cable or the fluid line from the lever, removing the grip from the handlebar, loosening the screw of the lever, and replacing it with a new one. You can also reconnect the cable or the fluid line and adjust the tension if needed.

Contaminated brake fluid 

The brake fluid is the part of the hydraulic brake system that transfers the force from the lever to the caliper. If the brake fluid is contaminated with air, water, or dirt, it can reduce the braking power or cause the brakes to lock up. This can be dangerous and damage the brake system. 

The solution to this problem is to bleed the brake system and replace the fluid with a fresh one. You can do this by using a bleed kit, following the instructions from the manufacturer, and pumping the fluid through the system until it is clear and free of bubbles.