Disk brakes along the rim of the wheel?

[Raama]

Disk brakes along the rim of the wheel??

Hi friends,
I have a doubt. I heard that when we keep the disc brake along the rim of the wheel, less energy is required to stop the wheel. Why is it so?? Why is it not used in today's bikes?

 

[ashishsinghal]

when we keep it along the rim of the wheel then torque about center of wheel increases and bike stops sooner

 

[Phrak]

Disk brakes consist of a pair of calipers squeezing two parallel surfaces. Caliper brakes on a bicycle consist of of a pair of calipers squeezing the rim of the wheel. The rim surfaces are fairly parallel.

Congratulations, you've reinvented the bicycle caliper brake.

 

[Lsos]

Hi friends,
I have a doubt. I heard that when we keep the disc brake along the rim of the wheel, less energy is required to stop the wheel. Why is it so?? Why is it not used in today's bikes?

Not less energy, just less force.

At the rim you won't have to squeeze as hard, but rim is moving faster, so more wheel will slide past the caliper before is stops. At the hub the torque is much greater, so you will have to squeeze much harder...but the hub is moving slower, so less wheel will slide past the caliper before it stops.

In the end, the squeeze force x area swept will be the same wherever you place the brakes.

 

[PJC01]

I can provide some insight into this question. Disk brakes along the rim of the wheel were commonly used in the past, but they have been largely replaced by other types of braking systems such as drum brakes or disk brakes mounted on the hub of the wheel.

The main reason for this shift is due to the design and function of the braking system. Disk brakes along the rim of the wheel require a lot of force to be applied to the rim itself in order to stop the wheel. This can cause excessive wear and tear on the rim, leading to potential damage and a shorter lifespan of the wheel.

In contrast, disk brakes mounted on the hub of the wheel use a caliper and brake pads to apply pressure to a disk rotor attached to the hub. This allows for more precise and controlled braking, with less force being applied to the wheel itself. This results in less wear and tear on the wheel and a longer lifespan.

Additionally, the placement of the braking system on the hub allows for better heat dissipation, which is important for maintaining the effectiveness of the brakes. Rim-mounted disk brakes do not have this advantage and can overheat more easily, leading to decreased braking performance.

In summary, while disk brakes along the rim of the wheel may require less energy to stop the wheel, they are not as efficient or effective as other types of braking systems. This is why they are not commonly used in modern bikes.