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Comment by mach5 | Hacker News Reader

to say i don't use the brakes is a little bit of a misnomer, as i use them at stoplights in order to activate the rear brake lights for other drivers. two more bits of trivia: the brake lights activate during regen for more than .2g of deceleration, and the brake rotor metal is formulated not to rust.

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I'm pretty sure taking your foot entirely off the gas pedal when in "L" mode actually activates the brake lights.

It does on the Tesla.

And anything with regen because of this:

UN Regulation on Stoplight Activation:

http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/...

Electric regenerative braking systems as defined in paragraph 2.17., which produce a retarding force upon release of the accelerator control, shall generate the signal mentioned above according to the following provisions:

<= 0.7 m/s/s The signal shall not be generated

> 0.7 m/s/s and <= 1.3 m/s/s The signal may be generated

> 1.3 m/s/s The signal shall be generated

It's made of metal, its going to corrode in some way - I don't think stainless steel has the properties you'd want in a brake rotor, either.

Well, it could be ceramic, which is what some competition cars use, and that wouldn't rust. But I doubt it.

Ceramic brakes don't work well when they're cold, so you don't want to use them on a car where the main use case is a cold panic stop.

There are <$100k cars that have had ceramic brakes as a factory option, but it's not a good option.

He said 'metal' that implies not ceramic.

Which was second-hand information, and light on details, and thus possibly mistaken. As I stated, possible, but I didn't think it likely.

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