In comparison with the fixed-caliper brake, the frame-caliper brake, like the floating-caliper brake, basically requires half the number of pistons and cylinders. The force, in this case is applied only to one side,
thus allowing the brake fluid to be kept away from the sometimes very hot brake-disc more effectively.
It is sometimes also called a sliding-caliper brake. The shoe is mounted onto the suspension. Through two grooves it can be shifted in relation to the disc, along a line parallel to the axis of rotation of the disc, the pads are
applied to both sides of the disc. On the inside there is space for the piston/cylinder unit. When braking, the piston presses directly onto the inside brake pad, whereby the cylinder and caliper, thus the outer brake pad as
well, are drawn inwards. Problems with a sticky shifting mechanism can be observed when releasing the brake. In the subsequent floating-caliper brake, the connecting groove between the caliper and the shoe has been
constructively altered by replacing this with a specially sealed pin-guide.
The forerunner of the floating-frame brake was the floating-saddle brake. In this case, the frame and the shoe were connected by wedges with each other. The piston and cylinder were also incorporated into the shifting
mechanism. Unfortunately, after a number of years of winter operation, this method had even more problems relating to the flawless withdrawal when releasing the brakes. 01/12