ya que habalmos de fisica, los frenos transforma la energia cinetica en calor, la pastillas necesitan calor para frenar y a distinta tenmpteraturas el coeficiente de friccion cambia, si no se llegas a un temperatura minima la mordida es debil, intenta frenar en frio con una partillas de freno para carreras tipo las ferrodo DS3000 parece que tuvieses dos tacos de madera. El ejemplo de la bicicleta no sirve aqui no hablamos de la teoria de arquimides, propiedades de la palanca
aqui tienes un grafico de la pagina de ferodo
y unas palabritas del tecnico de Stoptech que sabe mas que nosotros y que he repetido varias veces y como que no me escuchan, a ver si a este le escuchan, lo tengo dentro de mis articulos preferidos
There are a few basic facts that must always be kept in mind when discussing brake systems:
1) The brakes don't stop the vehicle - the tires do. The brakes slow the rotation of the wheels and tires. This means that braking distance measured on a single stop from a highway legal speed or higher is almost totally dependent upon the stopping ability of the tires in use - which, in the case of aftermarket advertising, may or may not be the ones originally fitted to the car by the OE manufacturer.
2) The brakes function by converting the kinetic energy of the car into thermal energy during deceleration - producing heat, lots of heat - which must then be transferred into the surroundings and into the air stream.
3) Repeated hard stops require both effective heat transfer and adequate thermal storage capacity within the disc. The more disc surface area per unit mass and the greater and more efficient the mass flow of air over and through the disc, the faster the heat will be dissipated and the more efficient the entire system will be. At the same time, the brake discs must have enough thermal storage capacity to prevent distortion and/or cracking from thermal stress until the heat can be dissipated. This is not particularly important in a single stop but it is crucial in the case of repeated stops from high speed - whether racing, touring or towing.
4) Control and balance are at least as important as ultimate stopping power. The objective of the braking system is to utilize the tractive capacity of all of the tires to the maximum practical extent without locking a tire. In order to achieve this, the braking force between the front and rear tires must be nearly optimally proportioned even with ABS equipped vehicles. At the same time, the required pedal pressure, pedal travel and pedal firmness must allow efficient modulation by the driver.
5) Braking performance is about more than just brakes. In order for even the best braking systems to function effectively, tires, suspension and driving techniques must be optimized. Para que no me vengan con el tema de que los porsche y BMW y mercedes y ferraris usan discos perforados.. una palabra, MARKETING al hacerle huecos disminuye la superficie de frenado y resitencia a lcalor por lo que tuienen que hacerlo mas grande los discos que se ven "guay" en las llanta gigantes que montan los coches hoy en día.
Mi amigo el ingeniero dice:
Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing. Most racing rotors currently feature a series of tangential slots or channels that serve the same purpose without the attendant disadvantages.sobre los disco sobredimensionados mi amigo el ingeniero dice
INCREASING DISC DIAMETER
The problem with increasing the effective radius of the discs is that, since the designers used the largest rotor that would fit inside the wheel. Typically, increasing the rotor diameter means increasing the wheel size. The expense involved is only one objection. A major issue is the impact on of the OE suspension geometry.
The camber curves and roll resistance characteristics of any proper suspension system are designed for tires with a specific sidewall height and stiffness. Increasing the wheel diameter means decreasing the sidewall height and the compliance of the tire. Carried to an extreme, this will hurt cornering capability and might actually result in a loss of braking traction due to "edging" the front tires under heavy braking. And although technology is making possible ultra low and stylish tire side wall heights, it does not necessarily result in ultimate performance, just take a look at the sidewall height of Formula One and Indy cars.