View attachment 1715111876When dual reservoir master cylinders originally made it onto the scene, one of the reservoirs was much larger than the other. This was generally considered the reservoir for the drum brakes due to the sheer volume of fluid needed to push the brake shoes out followed by the return of all that fluid back to the master cylinder. Disc brakes didn’t require the same volume in the reservoir. Today, most master cylinders have the same size reservoir as well as masters sharing the same reservoir. These are still considered dual reservoir systems because the internals are separated front to