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brake lever is transferred to a cylinder and the brake shoes. In spite of many advantages, these brakes are

being used less and less, even though the last disadvantage has been eliminated. The disadvantage was that

in order to remove the wheels, you would have to let the air out of the tires. This was solved by designing a

brake so that the brake arms could be opened up so that the wheel could be taken off with out letting the air

out.

Disc Brakes

Despite the good track record of the cantilever brake, the search for an effective disc-brake system

has started. A new bike company in California, Mountain Cycles, introduced a hydraulic “Pro Stop” disc-

brake system in 1990. Aluminum discs (located at the hub of the wheel) have brake shoes made from a

low-temperature fibre material. These brake shoes grip the disc in a “pinching” fashion. The brake shoes,

together with the aluminum disc, don’t lose power under wet conditions. Power from hand pressure is

perfectly transferred to the brake shoes. These disc brakes were developed in conjunction with a front-

wheel suspension system. Their weight including fork is 53/4 lbs (2.6 kg). This system can also be mounted

on conventional Unicrown forks.

Brake Levers

The brake lever has been used ever since the mountain bike was invented. It has gone through

improvement over the years in ergonomics, size, weight, and the way it performs. The lever pulls a brake

cable, which transfers the pulling action of the brake arm of the cantilever to the brake shoe. The lever was

shortened after it was discovered that it can be operated with only two fingers. There is also a brake lever

with a roller mechanism, called the “Servo Wave”. When this lever is used, the pivot point changes the

relation to the cable carrier, which causes the brake shoes to come closer to the rim. The closer the brake

shoes get to the rim, the more effective the transfer of power from the lever to the brake shoes. All

accomplished with a minimum amount of pressure applied to the brake lever at the handle bars.

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