Saw a commercial on late-night TV for some sort of "rotor-truing" devices... Basically looks like two big arasive pads you put in place of your brake pads, run the rotors up to speed, hit the brakes and *voila!* it grinds off enough material to "re-true" the rotors. They CLAIM (of course) reduced stopping distances and longer brake life (duh)...
I have mixed feelings about this... Any thoughts (from someone more knowledgeable than I)?
Anyone seen these things yet?
They're just a nominal fee plus the cost of new rotors. Seriously, though I haven't seen them, first impression is that it's just informercial bunk. There has to be something that keeps them square to the axle; otherwise they'll just follow the profile of the rotor faces as they cut (gouge) them, and nothing will improve.
I assume these are either "Not legal for street use" or they're DOT-approved brake pads with a coarse composition?
I assume these are either "Not legal for street use" or they're DOT-approved brake pads with a coarse composition?
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AZhitman
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They appear to be some sort of coarse, abrasive compound. I'm not sure if they are to be installed OVER or inplace of your brake pads.
The commercial shows them running the rotors up to speed, then applying the brakes fast and hard. A hellacious noice and a cloud of dust, and then they mic the rotors...
I'll see if I can find a link to them. Wild weird stuff.
The commercial shows them running the rotors up to speed, then applying the brakes fast and hard. A hellacious noice and a cloud of dust, and then they mic the rotors...
I'll see if I can find a link to them. Wild weird stuff.
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Q451990
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With the brake calipers floating on the pins - I don't see how they could true the rotor... Maybe they could deglaze them or get rid of grooves. Given the amount of work to get to the brake pads - I can't imagine swapping them out to true the rotors - you're almost down to the point where you can remove them and have them turned anyway!
Maybe I'm missing something though - hopefully you'll find a link!
Heath
Maybe I'm missing something though - hopefully you'll find a link!
Heath
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lessthanjakejohn
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lessthanjakejohn
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Well I read it, and they make a great presentation, but I think they really sweep parallelism and runout under the rug with a spell and a wave of their hands. At least they admit the product wont affect parallelism and runout, but to say that you won't notice anomalous rotors anymore is a lie I think. It used to be that a scored rotor was a bad thing. Now suddenly a scored rotor is the key to better stopping distance, cooler brakes, and a better ride. "Independent Testing" can be spun to project just about anything you want. Beware of words like "up to", "virtually", "nearly", etc. Also, they make a big deal about all this extra surface area, but the normal component of total friction force will always be the same with the same brake pedal force, unless you actually get brakes with a larger pad footprint.
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Q451990
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Sounds like it's just supposed to de-glaze and clean the old pad material off. This somehow is supposed to let your new pads seat better and reduce the possibility of warping... kind of a weird claim... "it does this, but maybe it'll stop this problem unless you have another problem...$20 please"
Heath
Heath
