Understanding Bicycle Braking 

Customers purchasing new bicycles today in 2026 will be shown the advantages of hydraulic disc brakes. Cyclists who use wider tyres, such as those found on mountain bikes, largely agree that hydraulic brakes offer better stopping power.  However, there are still many supporters of rim brakes, particularly among road cyclists. 

Understanding how to use braking systems correctly is important for both your safety and your performance when cycling.

Why Technique Matters

It’s important to use the correct braking technique when cycling. As a child, you would have been told to pull on your back brake first to avoid going over the handlebars. This may work for children moving at low speeds, but if an adult travelling at a faster speed pulls only the rear brake in the situation of a crash, the rear wheel would lock and the cyclist would continue in motion, hitting the object that he wished to avoid. This skidding of the wheel may cause panic and a complete loss of control of the bicycle.

Newton’s First Law states that an object in motion stays in motion at the same speed and direction unless acted upon by an external force. In the event of a car crash, if you are not wearing a seat belt, your body continues moving forward when the vehicle stops, increasing the chances of an injury. The same principle applies to a cyclist.

At higher speeds, proper technique is essential:

1. Lock your arms at the elbows
2. Transfer body weight to the balls of your feet over the pedal axle
3. Keep your body low and shift weight towards the rear
4. Apply both brakes — using approximately 70% force to the rear and 30% to the front.

When this position is adopted, you pull the front brake slightly before the rear brake; braking specialists commonly refer to this as the 70/30 rule.

Using the correct technique prevents excessive rear rim wear and improves stopping efficiency.

The Development of Bicycle Braking

Over the last 50 years, bicycle braking systems have evolved significantly.

Steel Rod Brakes

The earliest common system was the steel rod brake, used on bikes known as “high nellies.” From the lever, there was a return spring, and attached was a tab and rod that had a square hole fitted onto the lever. This was inserted into the brake shoe, which had the brake blocks attached. This brake shoe had two spigots on its end that ran through brake guides and were attached to the bicycle forks. Pulling the lever engaged the rubber brake blocks with the steel rim and brought the bike to a stop.

The system was mechanical, heavy, and complex — but it worked for its time.

The Caliper Brake

The calliper brake introduced a handlebar lever connected by a steel braided cable to a brake calliper. The wheel rim was designed to have flat braking surfaces that allow rubber brake blocks to grip and slow the bike effectively.

With the introduction of aluminium and alloy rims, braking performance improved significantly, especially compared to steel rims in wet conditions.

Many attempts were made in recent years to make braking more efficient with the introduction of centre pull brakes. Cantilever and V-brakes later improved on calliper systems with stronger arms and better return springs. V-brakes, in particular, mounted on threaded bosses attached to the fork blade, offered increased braking power.

Mechanical Disc Brakes

Mechanical disc brakes introduced a rotor mounted on the wheel hub. The lever has a braided cable going down to the brake unit. When it is pulled, the two brake pads clamp onto the rotor.  

Disc brakes became standard on motorbikes in the 1960s, and it was clear they would eventually become standard on bicycles.

Advantages:

• A greater distance from the top of the tyre to the under edge of the fork crown permitted a cyclist to use a wide or narrow tyre on the same bike.
• Wider tyres allow for a softer ride. By pumping the tyre to 70 psi instead of 110 psi, you feel a softer glide over the road surface rather than the bumpy feeling the higher tyre pressure gives.
• Strengthening the frame to accommodate the brake unit at the bottom of the fork can give a stiffer ride, which is preferred by some cyclists

Disadvantages:

• More difficult servicing and maintenance.
• Large variety of brake pads, meaning bike shops must stock over 100 different brake pads, whereas there are fewer than 10 different types of brake blocks and shoes for calliper brakes.
• Disc brakes tend to be noisier. Riders become familiar with the shudders and squeaks of disc brakes; this is mainly due to the rotor getting contaminated with oil or dirt from the road, which in turn contaminates the pads. The best solution would be to install a new rotor and pads.
• Harder to visually inspect pad wear. As the pads are less obvious, it is more difficult to know when they are worn and need replacing. 
• Failure to replace worn pads can damage rotors and seize pistons.

Hydraulic Disc Brakes

Hydraulic brakes are very much in fashion at the moment. 

They operate using fluid rather than a cable, and require very little hand force — braking can often be done with one finger.

Many riders believe hydraulic brakes offer better modulation than rim brakes. Others argue that rim brakes provide earlier feedback through cable tension, whereas hydraulic systems may engage more abruptly, as you do not feel resistance until after the pad engages with the wheel rotor.

It is generally accepted that hydraulic disc brakes are a better option for mountain bikes when descending steep hills at speed with wide tyres.

Most modern systems now use mineral oil. It is a better lubricant and is becoming the standard, but due to its ability to absorb air, the systems may require bleeding 2-3 times a year. Shimano have always used mineral oil, and SRAM has moved from DOT fluid to mineral oil systems. DOT did have its advantages; it had a harder feel when pulling the brakes, which many riders preferred, as it didn’t suck in air.

Mixing DOT 5 and mineral oil in your braking system will destroy the seals and lead to premature brake failure. Regular inspection is essential.

Real-World Brake Wear: A Shop Example

A worn brake pad was recently removed in our shop from a Merida road bike sold just nine months earlier. It was ridden regularly on challenging hills, which meant significant pressure was being applied on the brake pads downhill. In the 9 months, it had been ridden 10,000 kilometres

When the pads wore down to bare metal, they damaged the wheel rotor and caused the piston to seize. The entire brake unit, rotor, and mineral oil had to be replaced.

Manufacturers recommend pad replacement between 5,000 and 8,000 kilometres. Aggressive riders should inspect more frequently. Leisure cyclists may reach 15,000 kilometres before replacement. Failure to inspect can result in costly repairs.

….

As can be observed from this set of Mavic wheels, the cyclist uses his rear brakes most of the time, thus the wear on the rear rim. This customer cycles with a cycling club and would be doing around 10,000 Kilometres per year.  If he used the maxim of 70/30, this would not have happened.

Regular inspection of pads, proper fluid management, and disciplined braking technique will improve safety, reduce wear, and extend the life of your braking system.