A rim rotor braking system has an integrally formed rotor portion that is orientated at 90 degree to the rim. The rotor is compressed between calipers in a braking system that is attached to a portion of a vehicle such as a bicycle fork. The rotor's orientation maximizes heat transfer to the air and allows the braking system to efficiently stop the vehicle. The brake system may be mounted under the fork or adjacent to it. The rim may be made of aluminum, titanium, steel or any other suitable material. The braking mechanism may be mechanical, hydraulic or electric. In one embodiment, dual rotors are disposed on either side of the rim to provide extra braking power. In yet another embodiment, the rotor is replaceable.