FAQs

What is brake bleeding?

Brake bleeding is the process of removing air from a hydraulic brake system.

How do hydraulic brakes work?

Pulling your brake lever creates pressure in the hydraulic fluid. Because fluid does not compress easily, that pressure travels through the brake line to the caliper, where pistons push the brake pads against the rotor to slow the wheel through friction.

Why do my brakes need to be bled?

If your brake lever pulls all the way or nearly to the handle before engaging, you likely have “spongy brakes” caused by air in the system. Air compresses easily, so instead of transferring force to the caliper, the lever is compressing air bubbles in the line, reducing braking performance.

How does air enter the brake system?

Air can enter when brake pads become worn and fluid levels drop, during maintenance such as shortening hoses or replacing components, or through leaks in damaged calipers or hoses.

Do I need to completely flush my brake system?

Over time, brake fluid can become contaminated or break down, which reduces performance. Flushing the system removes old fluid and contaminants, helping maintain proper viscosity, heat resistance, and overall braking performance.

How often should I bleed my brakes?

You should bleed your brakes whenever performance drops or the lever feel becomes spongy. Many riders also perform a full bleed every 1–2 years as preventative maintenance.

How difficult is it to bleed brakes?

Brake bleeding is a straightforward process. Once you’ve completed your first bleed, it becomes a simple and repeatable maintenance task.

What do I need to bleed my brakes?

You’ll typically need the correct brake fluid for your system, a compatible bleed kit, gloves, and basic hex or Torx tools.

How do I figure out which kit to purchase?

Start by identifying your brake model. Most brakes have the brand printed on the lever or caliper, which may differ from your bike brand since many manufacturers use Shimano, SRAM, Magura, Tektro, and others. Once identified, choose the kit designed specifically for your brake system to ensure correct fittings and compatibility.

How are the Basic, Standard, Master, and Pro kits different?

We offer four kit levels: the Basic Kit includes only essential fittings and components needed to perform a bleed if you already have fluid and tools, the Standard Kit adds brake fluid for a more complete setup, the Master Kit includes everything in Standard plus a dedicated bleed tool for easier servicing, and the Pro Kit includes everything in Master with upgraded professional-grade syringes for smoother operation, improved durability, and more frequent or heavy-duty use.

How much brake fluid do I need to bleed my brakes?

Typically, 10ml of mineral oil is needed for a front brake and 15ml for a rear brake. In total, 60ml is usually enough to bleed both front and rear brakes on two bikes. If you’re new to bleeding brakes or want extra margin, we also offer kits with 120ml of mineral oil.

What is a bleed block?

A bleed block fits between the caliper pistons to prevent them from moving during the bleed process. If you don’t have one, a 10mm Allen wrench can be used as a substitute.

Is your kit compatible with my brakes?

Check our compatibility list to confirm which models are supported. Our Shimano road and gravel kits are also compatible with Shimano mountain bike brakes—the road/gravel version simply includes an additional funnel adapter.