Brake fluids and mineral oils

Brake fluids and mineral oils are essential components of the brake systems of many modern bicycles, especially those with hydraulic disc brakes.

What types of bicycle brake fluids are there?

Hydraulic disc brakes typically use brake fluids that come in two basic types: DOT (Department of Transportation) and mineral oil.

DOT brake fluid: This type of brake fluid is a synthetic fluid that meets specific Department of Transportation standards. DOT brake fluids are known for their high boiling points, which help prevent brake fade during heavy braking. They are commonly used in mountain bikes and some road bikes. DOT 3, DOT 4, and DOT 5.1 are common grades of DOT brake fluid, with higher numbers indicating a higher boiling point.
Mineral oil: On the other hand, mineral oil is a non-corrosive and non-toxic alternative to DOT brake fluid. It is commonly used in Shimano hydraulic disc brake systems. Mineral oil-based systems are valued for their consistent performance and ease of maintenance. They are less prone to absorbing moisture compared to DOT brake fluids.

When choosing between brake fluids or mineral oils for your bike's brake system, it is essential to follow the manufacturer's recommendations. Mixing the two types can lead to damage or failure of the brake system. Regular maintenance, including bleeding the brake lines, is essential to ensure optimal brake performance and safety.

Check out our video "Quick way to bleed Shimano brakes"