A guide to the different types of Brembo master cylinders [2024 Edition]

Brembo brake systems are used in the world's most prestigious races, including MotoGP. In the last article, we talked about calipers, so this time we will look at master cylinders! When it comes to brakes, we tend to focus on the calipers, but the master cylinder also has a huge impact on control and feel. For those of you who aren't sure what types of master cylinders there are to begin with, or don't know which one is right for you, why not take a look at this list?

Radial Pump Master Cylinders

RCS Corsa Corta Master Cylinder

Specifications
-Piston diameter: 19mm / 17mm / 15mm
-Recommended calipers:
　19mm -> Brembo 4pot x 2 (except 30mm same diameter)
　17mm -> Brembo 30mm same diameter 4pot x 2
　15mm -> Brembo 4pot x 1
-Lever ratio: 18/20mm, adjustable (RCS mechanism)
-Body material: Aluminum alloy (Forged)
-Weight: Approx. 400g
-Clutch master cylinder: Available
-Other: Built-in selector (brake only), overhaul possible

In addition to the Ratio Click System (RCS), the RCS Corsa Corta is equipped with a selector that allows the brake response to be changed in three ways.

N (Normal): Mild initial braking, ideal for city streets. It provides high braking force even on low-grip surfaces.
S (Sport): Stronger initial braking than Normal. This setting is recommended for aggressive riding.
R (Race): For even stronger initial braking, this setting provides the same sharp and immediate response as the master cylinders used on MotoGP machines.

Together with the RCS adjustment, 6 setting patterns are possible.

RCS Corsa Corta RR Master Cylinder

Specifications
-Piston diameter: 19mm / 17mm / 16mm / 15mm
-Recommended calipers:
　19mm -> Brembo 4pot x 2 (except 30mm same diameter)
　17mm -> Brembo 30mm same diameter 4pot x 2
　16mm -> Brembo 4pot x 2
　15mm -> Brembo 4pot x 1
-Lever ratio: 18/20mm, adjustable (RCS mechanism)
-Body material: Aluminum alloy (Forged)
-Weight: Approx. 380~400g
-Clutch master cylinder: Available
-Others: Built-in selector (brake only), overhaul possible

The popular Corsa Corta master cylinder, but with a machined body. It is CNC machined, making it lighter than conventional products. The lever is also machined to match the body and has a new shape for a comfortable grip. In addition, the lever end has a slit to prevent the lever from malfunctioning due to wind pressure at high speeds.

RCS Master Cylinder

Specifications
-Piston diameter: 19mm / 17mm / 15mm / 14mm
-Recommended calipers:
　19mm -> Brembo 4pot x 2 (except 30mm same diameter)
　17mm -> Brembo 30mm same diameter 4pot x 2
　15mm -> Brembo 4pot x 1
　14mm -> Brembo 2pot x 1 (for rear)
-Lever ratio: 18/20mm, adjustable (RCS mechanism)
-Body material: Aluminum alloy (Forged)
-Weight: Approx. 400g
-Clutch master cylinder: Available for all except 15mm
-Other: Overhaul possible

RCS stands for "Ratio Click System". By turning the adjuster on the front of the lever 180° with a screwdriver, the distance between the contact point and the fulcrum of the master cylinder push rod can be increased or decreased by 2mm, and the lever ratio can be selected between 18mm and 20mm (red indicates 18mm and black indicates 20mm). This makes it possible to control the distribution of braking force.

RMC Forged Brake Master Cylinder

Specifications
-Piston diameter: 19mm / 16mm
-Recommended calipers:
　19mm -> Brembo 4pot x 2 (except 30mm same diameter)
　16mm -> Brembo 4pot x 2
-Lever ratio: 18mm
-Body material: Aluminum alloy (Forged)
-Surface treatment: Hard anodized
-Weight: Approx. 310g
-Clutch master cylinder: None
-Other: Overhaul possible

This is the most standard product among Brembo's radial pump master cylinders. It has no adjustment mechanism other than the lever distance, but this makes it reasonably priced. Even at this price, it has a forged body for improved response and controllability in all conditions.

There's a lot to consider when choosing master cylinders

Brake master cylinders are divided by construction, piston diameter, and adjustment mechanism. There are many criteria for selection such as whether it is a radial or axial pump (semi-radial has been discontinued), what caliper is used, whether it is a standard model, RCS, Corsa Corta, and so on. In particular, be very careful in selecting the caliper in relation to the piston diameter. If you make a mistake, you may end up with a loose lever touch or a stiff touch with almost no stroke. Please refer to the recommended calipers in the specifications listed for each type of master cylinder!