What are the benefits of changing your motorbike’s brake fluid

Motorbike brake fluid does a lot of good, make sure you change it regularly!

More and more motorbikes are now using hydraulic disc brakes, which use what is known as brake fluid to transfer pressure. The condition of the brake fluid is a matter of life and death for motorcyclists and should be checked regularly and should never be taken lightly!

The front brake generates pressure from the master cylinder at the base of the brake handlebar. When the brake handlebar is held, the piston inside the master cylinder exerts pressure on the brake fluid. This pressure is transmitted through the brake pipe to the piston in the brake caliper, which is pressed out and presses the brake block against the disc.

motorbike's brake fluid (2)

This configuration sports “Pascal’s Law – the constant magnitude of pressure applied to a sealed fluid is transmitted from fluid to fluid in all directions”, using the fact that the area of the piston in the caliper is larger than the area of the piston in the master cylinder to dramatically increase the force used to operate the brake handlebars. With this configuration, even a less powerful rider can generate enough braking force to bring a heavy motorbike to a stop.

Why change brake fluid: When it comes to vehicle maintenance, every car lover can say a few words about brands, engines and fuel consumption, but when it comes to brake fluid, very few people really know anything about it. Why do we need to check and replace brake fluid on a regular basis? To use a professional explanation, brake fluid will have a lower boiling point after a period of time, and will be contaminated and oxidised to varying degrees.

Brake fluid itself is a very stable pressure fluid that is not easily degraded by chemicals or high temperatures, but has a quirk in that it will absorb water from the air. The biggest headache is the brake hydraulic system, which must be connected to the atmosphere outside the system in order for it to work properly, so the cap of the fluid pot will have a vent.

In this way, the brake fluid will absorb the moisture in the air, such as the moisture not completely wiped clean when washing the car, the humid air in the rainy season, etc., which may be absorbed over time, and in the brake system for a long time or in the process of emergency braking, it will make the brake fluid temperature rise rapidly, and under the high temperature, the moisture will be converted into gas, so that the effectiveness of the brakes will be reduced. In layman’s terms, fluids are incompressible, just like we can’t buy compressed water on the market?

But gases can be compressed, and you can easily buy small cans of compressed air for insecticides, air fresheners and the like in the supermarket. Just that little bottle of the stuff could fill at least the whole compartment of an ordinary car. In other words, the air in the whole compartment of an ordinary three-door car, if compressed, could be filled with just such a small can.

Imagine if there was a certain amount of air in your braking system, would the air in the system be compressed when you squeeze or apply the brakes, assuming that a ‘healthy’ braking system filled with brake fluid produces 10 braking force when you squeeze the brake handle, then an ‘unhealthy’ braking system containing half the air would produce only 5 or less when you squeeze the brake handle.

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