Most cars today have front disc brakes,and these are equipped with brake calipers. They’re quite possibly the most important part of your car braking system because you need brake calipers in order to stop. Understanding how brake calipers work and the role they play in bringing you to a stop can be helpful in understanding how the different systems of your car function.
Construction Of The Caliper
The brake caliper fits over the brake rotor. Attached to the caliper is a pair of brake pads, which can be replaced when they wear down. When you press down on the brake pedal, it causes the fluid in the brake line to push the pistons in the brake caliper. In turn, this causes the brake pads to engage with the brake rotor, which slows the car down to an eventual complete stop.
Types of Calipers
You’ll find two major types of brake calipers on vehicles. There are fixed calipers and floating calipers. With fixed calipers, which are favored because they offer better performance, the pistons are on each side of the rotor. These calipers remain in one place and don’t move at all.
By contrast, floating calipers can move, but the movement is in and out and relative to the rotor. The piston (or pistons, since some have one piston and others have two) is on the inside of the rotor. The entire brake caliper is pushed by the piston once the brakes are applied, which forces down the brake pads on both sides of the rotor.
There are also some kinds of fixed brake calipers that offer extremely high performance. These will contain at least two pairs of pistons on each side of the rotor, and can go up to six pairs. Given that fixed calipers are more expensive that floating brake calipers, the high performance fixed calipers command an extremely high price, which is why they’re very rarely seen on street vehicles.
Brake Caliper Tool
A brake caliper tool is important when you’re replacing brake pads on your brake calipers. You use it to force the piston back into the caliper. This gives you the room necessary to remove the old brake pads and fit new ones. You’ll also use it when removing the calipers to work on them or rebuild them.
Motorcycle Brake Calipers
Most larger motorcycles use disc brakes on the front wheel, with the brake calipers attached to the forks. Because motorcycles are quite lightweight compared to cars, they tend to use more pistons, often up to four, in order to apply the brakes.
Pickup trucks and SUVs tend to come with floating brake calipers. However, these are often changed as people add aftermarket equipment. This is especially true if the vehicles weight is increased and greater stopping power becomes necessary. This is achieved by increasing the surface area between the rotor and the brake calipers. This helps lessen the heat, which can be an enemy of good braking and cause brake fade.