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No combination of pad and rotor will eliminate that. It's simply physics.

E9X models incorporate brake drying where the pads and rotors are momentarily grazed against one another periodically in rain to eliminate this delay.
I get that it's physics of water getting on there causing the issue. I just know that some cars don't really have this delay, while others do. How much of that is the from the materials of the rotor and pad combination or from the fact that our alloy wheels are much more open, allowing more water onto the brakes vs. steel wheels with hub caps, I don't know.

I did not know that the E9X models did this, very cool. Does it use the rain sensor on the windshield to determine that the conditions require the brake drying, or is there another sensor somewhere that handles that?
 

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You should read a little more Drewfus. You don't need to turn your rotors unless there's a reason to, and honestly, if there's a reason to, you should probably just get new rotors. It's not worth it to toss money away on turning.

At 50K miles, if you needed turning, then in all likelihood you'll reduce the rotors to below minimum thickness. Maybe not, but certainly it'll shave miles off of them.

You also only have 2 sensors, not four.

Rotors don't really warp.

Finally, read jpr's thread on brakes--good stuff from a great Fanatic. Take his word to the bank!
Brake pads get 'etched' into the rotors, and create a rough surface that is unique to the pad and rotor. So each pad and rotor fit together kind of like a key, with the little grooves.

If I just took a grooved rotor and put a smooth pad on there, it would eat into the pad in that same pattern. That is why you always either 'turn' a rotor or put on a new one.

There is no reason to buy new rotors unless turning them takes the thickness below the minimum. Also, turning costs about $10 per at any O'riley auto parts.

Thanks for the tip on sensors. I thought each wheel used one.

Rotors DO warp. I've driven plenty of cars with warped rotors. Our cars might not have that problem, with the rotor design though. But if you take a car with a thinly designed rotor, and get the rotor hot through braking, then cool it down quickly by driving through rain, it will warp. You'll feel it when you brake hard and have the steering wheel shimmy from side to side.
 

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Brake pads get 'etched' into the rotors, and create a rough surface that is unique to the pad and rotor. So each pad and rotor fit together kind of like a key, with the little grooves.

If I just took a grooved rotor and put a smooth pad on there, it would eat into the pad in that same pattern. That is why you always either 'turn' a rotor or put on a new one.

There is no reason to buy new rotors unless turning them takes the thickness below the minimum. Also, turning costs about $10 per at any O'riley auto parts.

Thanks for the tip on sensors. I thought each wheel used one.

Rotors DO warp. I've driven plenty of cars with warped rotors. Our cars might not have that problem, with the rotor design though. But if you take a car with a thinly designed rotor, and get the rotor hot through braking, then cool it down quickly by driving through rain, it will warp. You'll feel it when you brake hard and have the steering wheel shimmy from side to side.
That's pad deposits causing uneven surfaces on the rotors which in turn cause vibrations. Deposits occur from overheating. Rotor warp is a myth
 

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I get that it's physics of water getting on there causing the issue. I just know that some cars don't really have this delay, while others do. How much of that is the from the materials of the rotor and pad combination or from the fact that our alloy wheels are much more open, allowing more water onto the brakes vs. steel wheels with hub caps, I don't know.

I did not know that the E9X models did this, very cool. Does it use the rain sensor on the windshield to determine that the conditions require the brake drying, or is there another sensor somewhere that handles that?
I am not sure. The most logical guess would be incorporation of the rain sensor.
 

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You know that feeling you get when cruising on the highway in wet / rainy conditions and you start to tap the brakes for an off ramp... and NOTHING happens for the first second or two?!? :yikes: Does this combination of pad and rotor eliminate that?

Also, what series Greenstuff pad did you go with?

The 2 (well, 3 really) things I want to change about my brakes when I replace rotors and pads:

1.) The WBPF (Wet Brakes Pucker Factor)... OEM brakes I would rate at an 8.5, would like to see that reduced to a 4 or below.
2.) The absurd amount of rust on my rotors whenever it rains.
3.) Brake noise in general... I think that my rotors are rusting more since they are getting worn down and starting to get minor grooves, hence causing more noise than normal. I'd assume new rotors and pads would essentially get rid of brake noise under normal conditions.
Ive only had that once, and it was just a brief second. wasnt cool at all, but i was driving through the tail end of some hurricane and the rain was basically sideways.
bottom line tho, IT STILL STOPPED GREAT!

I cant say my brake pad/rotor combo improved or increased this, only what i just wrote.
The rotors are grooved and the pad has a single line slot down the middle, running radially when mounted. i THINK that combined with the grooves MAY be good for some cleaning. but thats just what i think.

I couldnt tell you what series they were, theyve been on the car since 07, and around 80k miles on em, and theyre still passed state inspection in Jan/12 with flying colors.

Seriously, i say with 100% confidence, that this brake combo is set and forget, and work well.

wish i knew what series they were tho, sorry.
I have them in my "basket" on amazon.com waiting for this set to even look ready for replacement, and 3 years later, theyre still in the basket.

These are the discs i have
 

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Rotor warp.
i will say this. i have seen rotors on motorcycles, full floating rotors, and ive seen solid 1pc rotors both types warp.
Physically verified on a lathe.

I do not believe this is a myth.
YES, a lot of it is brake pad deposit and hot spots that cause vibrations, but make no mistake. Ive seen rotors warp for whatever reason. And its not from a wrecked vehicle either.
 

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Discussion Starter · #27 ·
OP:

There are many choices of pads/rotors out there. The sky's the limit. Your car will work perfectly fine with aftermarket quality rotors and OEM pads.

You are to purchase the following without questioning:

www.bmaparts.com

Front Brembo blank (plain) rotors: $38.70 for pair
Part Number:BMW018591
Manufacturer:Brembo
Weight:13.240lbs.

Front Textar (OEM) pad set: $40.74
Part Number:BMW080530
Manufacturer:Textar
Weight:3.500lbs

Rear Brembo blank rotor set: $46.86
Part Number:BMW062934
Manufacturer:Brembo
Weight:11.530lbs.

Rear Textar (OEM) pad set: $47.16
Part Number:BMW066185
Manufacturer:Textar
Weight:2.300lbs.

Grand total: $173.46 (and yes, these are for your 2000 323i.)

That is the highest quality, lowest-priced set you can get for your car and is what I am personally running.
Well you did help me out last time when my tensioner pulley broke, so I do trust your judgment.

May I inquire a bit further... I would not mind spending more money to get better quality.

The $173 is a great price, however $273 not so bad either if that means I will get less dust and better performance.

Lastly from other threads and reviews I went through, I concluded that the Brembo rotors rust and that OEM are generally best bang for the buck. (I live in Canada, lots of snow and salt)

The Textar pads are OEM, which means lots of dust but great performance. I recently purchased a fancy set of rims and would hate for them to turn out like my OEM rims, they are caked on with brake dust that has embedded in the rim, thus absolving resale value.

P.S. I still regard performance as my #1 priority, and dust to be #2. I don't want to be running over any beagles...
 

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Well you did help me out last time when my tensioner pulley broke, so I do trust your judgment.

May I inquire a bit further... I would not mind spending more money to get better quality.

The $173 is a great price, however $273 not so bad either if that means I will get less dust and better performance.

Lastly from other threads and reviews I went through, I concluded that the Brembo rotors rust and that OEM are generally best bang for the buck. (I live in Canada, lots of snow and salt)

The Textar pads are OEM, which means lots of dust but great performance. I recently purchased a fancy set of rims and would hate for them to turn out like my OEM rims, they are caked on with brake dust that has embedded in the rim, thus absolving resale value.

P.S. I still regard performance as my #1 priority, and dust to be #2. I don't want to be running over any beagles...
I haven't hit a single beagle...saved the life of two deers a couple of weeks ago...all OE. I know you don't trust me as much as Mango, but Mango will probably vouch for my trustworthiness somewhat!

I can't keep saying OE here, though. I do that in a post and five others come in and recommend a,b,c,d,and e as superior and cheaper...though they won't tell you whether they're comparing directly to OE or not.

I also don't care about rust and don't know if my blanks have rusted coz I'm not so wheel obsessed as half the list. I only care about stopping.

You know the sound a jet makes when it lands...that beautiful sound you hear of the brakes grabbing and saving you from dying in a fiery ball. That's Textar...just quieted down a bit coz it's a car not a jet.

...and I'll just mention again that you might not need any rotors nor even pads in the rear, but I don't know until you measure them with a caliper.

New pads go on old rotors fine. My textar pads lasted 60K in the front and at that time all rotors were fine and the rear pads had half their life left. I also don't care about dust, you know. But remember what jpr said in his thread, which I hope you read. If the pads dust less, maybe they're wearing harder on the rotors...how long do they last with different pads. With an OE combination, you're assured of going the distance and stopping in the distance--rain, snow, sleet, beagle packs, whatever.

For almost every non-OE pad I've ever seen recommended, I've seen some comments how crappy they are. I won't say all, but many...and that's how I decided not to argue, and just use bmw parts on a bmw. I know...strange notion around here!

GL OP, especially if you chose something else! :lmao:
 

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I just put on EBC 400 yellow stuff high friction pads, damn they are grippy. Even at slow speeds. Cost me $210 shipped for all 4 wheels. They are as dusty or more dusty than OEMs
 

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Discussion Starter · #32 ·
Damnit dmax, how dare you bring logic and facts into this!

I'll be pulling my rims off roday and will measure and inspect my brakes. Preferably I'd rather replace everything in one go and not have to worry about it. I do love OEM brakes though, would be ashame to get something else that sucks.

Now Mr. Dmax, riddle me this, if OEMs are soo good, why do they fade so damn much. After a few rounds of hard braking, my oems are horrible, I slam the brakes and the car hardly slows down, its kind of scary.

P.S. Where is this jpr thread you speak of?
 

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Damnit dmax, how dare you bring logic and facts into this!

I'll be pulling my rims off roday and will measure and inspect my brakes. Preferably I'd rather replace everything in one go and not have to worry about it. I do love OEM brakes though, would be ashame to get something else that sucks.

Now Mr. Dmax, riddle me this, if OEMs are soo good, why do they fade so damn much. After a few rounds of hard braking, my oems are horrible, I slam the brakes and the car hardly slows down, its kind of scary.

P.S. Where is this jpr thread you speak of?
Small brakes heat up faster than larger brakes and cool down slower as well. Say for instance 330 brakes.

I wouldn't skimp on high quality either and that's why I made the choice I did. When you get the Brembo rotors, just rattle can primer the exterior before installing. You can tape off the rotor face if you'd like but some people just let the brake pads wipe the excess paint away. I'd probably cover them just for good practice. Get a cardboard box and cut a hole and put it over the rotor then go to town with your paint can. It's just surface rust anyway and doesn't affect anything.
 

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Damnit dmax, how dare you bring logic and facts into this!

I'll be pulling my rims off roday and will measure and inspect my brakes. Preferably I'd rather replace everything in one go and not have to worry about it. I do love OEM brakes though, would be ashame to get something else that sucks.

Now Mr. Dmax, riddle me this, if OEMs are soo good, why do they fade so damn much. After a few rounds of hard braking, my oems are horrible, I slam the brakes and the car hardly slows down, its kind of scary.

P.S. Where is this jpr thread you speak of?
search jpr as author and 'brakes' in the thread title...can't be too many of them around.

As far as fading, I don't know why you feel that, but I can guess that maybe you have an automatic and are on them a lot on hills or something.

I have a manual and when I use brakes, I use them hard. I don't track.

I'd read that using brakes softly and easily is actually bad on them...more likely to leave deposits, and when riding them (not good) heat builds up, even though you think you're using them easily.

Also, another reason you might get fade is if you haven't changed brake fluid in a while. Brake fluid is hydrophilic...water loving (calm down California...you misread that word!)...so if you get water or air in the line, as the brakes heat up, you'd have air pushing the piston, not brake fluid.

Those are the only reasons I can think of. If you're crazy on your brakes all the time, maybe I'm wrong about recommending OE. They make track pads that brake better when hot, but then you sacrifice braking when they're not hot...which is more usually the case on the street. Also, I'm pretty sure they wear a lot faster and dust a lot more.

Sorry about presenting facts; next time I'll just stop with truthiness and you won't know the difference!
 

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Ive only had that once, and it was just a brief second. wasnt cool at all, but i was driving through the tail end of some hurricane and the rain was basically sideways.
bottom line tho, IT STILL STOPPED GREAT!

I cant say my brake pad/rotor combo improved or increased this, only what i just wrote.
The rotors are grooved and the pad has a single line slot down the middle, running radially when mounted. i THINK that combined with the grooves MAY be good for some cleaning. but thats just what i think.

I couldnt tell you what series they were, theyve been on the car since 07, and around 80k miles on em, and theyre still passed state inspection in Jan/12 with flying colors.

Seriously, i say with 100% confidence, that this brake combo is set and forget, and work well.

wish i knew what series they were tho, sorry.
I have them in my "basket" on amazon.com waiting for this set to even look ready for replacement, and 3 years later, theyre still in the basket.

These are the discs i have
Awesome, thanks man. I would definitely believe that the groove helps to clear the water off faster and allow the brakes to bite faster in wet conditions.

Has the braking surface on the rotor ever gotten rusty from sitting in the rain after this many years of wear? I know they are coated, but I don't know if that coating is only intended to protect them for a certain time frame, or if it is supposed to last the life of the rotor. I checked ATE's website, but it didn't give any information that detailed.

upon doing some searching on the webs, i would guess my EBC green stuff are 2000 series.
I assumed as much, but figured I'd ask in the event that you went with another one for a specific reason.

I'm pretty certain that when 'brakes time' rolls around, this is the route that I'm taking. (Haha, 'brakes time' would roll around... since you can't stop the rolling... :lmao:)
 

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Awesome, thanks man. I would definitely believe that the groove helps to clear the water off faster and allow the brakes to bite faster in wet conditions.

Has the braking surface on the rotor ever gotten rusty from sitting in the rain after this many years of wear? I know they are coated, but I don't know if that coating is only intended to protect them for a certain time frame, or if it is supposed to last the life of the rotor. I checked ATE's website, but it didn't give any information that detailed.



I assumed as much, but figured I'd ask in the event that you went with another one for a specific reason.

I'm pretty certain that when 'brakes time' rolls around, this is the route that I'm taking. (Haha, 'brakes time' would roll around... since you can't stop the rolling... :lmao:)
OK... even DMAX's jokes aren't that bad. :lmao:
 

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Also, another reason you might get fade is if you haven't changed brake fluid in a while. Brake fluid is hydrophilic...water loving (calm down California...you misread that word!)...so if you get water or air in the line, as the brakes heat up, you'd have air pushing the piston, not brake fluid.
Hygroscopic not hydrophilic
Moisture from the air contaminates the brake fluid then boils at operating brake temperatures, creates steam and becomes a compressible fluid creating a spongy brake pedal feel. Flush your fluid frequently to maintain a firm pedal feel and prevent internal rusting of caliper pistons and cylinders.
 
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