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RF,
should your brake-fluid go boiling (3x knock-knock), then you will have NO BRAKES at all. No brakes. Completely. Entirely. You're flooring the brake pedal and nothing is happening. And this is when you do start shitting bricks.
Why that? Hydraulic systems rely on a property of fluids to be incompressible which means that the fluid going thru the hydraulic lines acts like a pushrod. But when the fluid goes boiling, there happens a steam in the hydraulic lines which isn't a fluid, but a gas - and all gases are compressible. And your solid pushrods start acting like springs and it no longer works since your brake pedal creates too little tension because it isn't designed to operate this way.
Bottom line:
you overheated the pads and rotors.
F = N x k (friction force ortogonal projection of the pressing force multiplied by the friction coefficient for the given friction pair) is only a spherical cow (fwiw, here in Mordor we say 'a spherical horse in vacuum'). The truth is that the k (the friction coefficient for the given friction pair, i.e. materials A and B which rub against each other) is temperature-dependent. That is why there are winter and summer tires. And that is why your brakes work differently right upon the start on a cold Feb morning and in a hot July rush hour.
Your options, you say?
1) drive smart, use engine braking (no, it isn't that braking when you first brake with the licence plate, then you brake with the front bumper, the radiator grille, the hood, the radiator - and finally with the engine)
2.1) try different rotor+pad combinations: different friction pairs work differently at different temperatures
2.2) keep the stuff clean: the brakes are the apparatus of transforming the kinetic energy into the heat energy of the ambient air. Being covered with mud (and rust and dust) they no longer dissipate the heat as effective as they do being clean. The main brake radiator is... correct, the wheel. So the cleaner the wheel and the more surface it has and the more light-alloy it is (it is a funny figure of speech to put light-alloy wheel afront of steel ones), the more braking capacity you have.
3) go with bigger brakes. I don't mean the pads (pads with bigger surface work better then small pads, but the difference isn't that significant although noticeable), I mean the rotors. Yes, it is the thing when the bigger is better: the increased rotor diameter means you place the brake pads further away from the rotor center - which it rotates around - which means the arm of force (Archimedes was an old fart, but damn clever one) goes increased and even applying the same pressing force onto the pad-rotor pair you create more brake on the wheel.
BTW,
Do you know what time it is? It's time to check the front axle drive things: all that grease in CV joints and moreover in hub bearings doesn't like the heat, especially when it comes with extra mechanical load.
Hope this helps,
Zig
posted by 188.134.4...
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