The stock rotors are garbage. Get the EBC stock replacements and it wont happen again. Theyre like 50 bucks a side. Dont bother with the slots , vents etc.

 

Oh yes it will, I've done it on a bet before. Warped a set in under 100 miles. Now if you want to say it was due to build up and not heat, I guess we can agree to disagree, but these were new pads and rotors. Not my car by the way.

Race cars use a much better brake setup, not a fair comparision. But put a set of normal rotors on one and then see what happens. Half a race, maybe.

 

Ok if you say so.

Just for everyone else who might want to know the truth. Here is part of a story the late Carrol Smith a long time racer/ engneer and well know chassie guy has to say on the topic of Warped brakes. He is not the only trained expert to have this opionion on this topic.


The "Warped" Brake Disc and Other Myths of the Braking System
by Carroll Smith
Myth # 1 – BRAKE JUDDER AND VIBRATION IS CAUSED BY DISCS THAT HAVE BEEN WARPED FROM EXESSIVE HEAT.

The term "warped brake disc" has been in common use in motor racing for decades. When a driver reports a vibration under hard braking, inexperienced crews, after checking for (and not finding) cracks often attribute the vibration to "warped discs". They then measure the disc thickness in various places, find significant variation and the diagnosis is cast in stone.

When disc brakes for high performance cars arrived on the scene we began to hear of "warped brake discs" on road going cars, with the same analyses and diagnoses. Typically, the discs are resurfaced to cure the problem and, equally typically, after a relatively short time the roughness or vibration comes back. Brake roughness has caused a significant number of cars to be bought back by their manufacturers under the "lemon laws". This has been going on for decades now - and, like most things that we have cast in stone, the diagnoses are wrong.

With one qualifier, presuming that the hub and wheel flange are flat and in good condition and that the wheel bolts or hat mounting hardware is in good condition, installed correctly and tightened uniformly and in the correct order to the recommended torque specification, in more than 40 years of professional racing, including the Shelby/Ford GT 40s – one of the most intense brake development program in history - I have never seen a warped brake disc. I have seen lots of cracked discs, discs that had turned into shallow cones at operating temperature because they were mounted rigidly to their attachment bells or top hats, a few where the friction surface had collapsed in the area between straight radial interior vanes, and an untold number of discs with pad material unevenly deposited on the friction surfaces - sometimes visible and more often not.

In fact every case of "warped brake disc" that I have investigated, whether on a racing car or a street car, has turned out to be friction pad material transferred unevenly to the surface of the disc. This uneven deposition results in thickness variation (TV) or run-out due to hot spotting that occurred at elevated temperatures.

In order to understand what is happening here, we will briefly investigate the nature of the stopping power of the disc brake system.



The rest of this info is available at

http://www.stoptech.com/tech_info/wp...rakedisk.shtml

The rest is a good read with a lot of good information.

For those that do not know Carroll Smith (1932-2003) was a successful professional race car driver, engineer, and author.

He began racing MGs while attending the University of Rochester. Entering SCCA events in Pensacola, Florida at the time, he was enlisted in the US Navy.

Carroll moved to Europe where he befriended John Cooper. Driving a Formula Junior Cooper, he won his first race. After waning success in the Cooper cars, he returned to the United States and began working with Carroll Shelby at the Ford Motor Company on the GT40 program, which was aimed at challenging Ferrari’s dominance at the 24 Hours of Le Mans endurance race. Smith was hired as the Team Manager.

After winning Le Mans with the GT40 cars from 1966 to 1969 (inclusive), Ford lost interest in the GT40 program. Smith moved to work with Tony Adamowicz to work on his F5000 car in 1969. Smith led the team to the championship that year.

After that victory, he began working on 'Prepare to Win'. Smith later consulted for the Ferrari Formula One team and in 1977 he was team manager for the Moffat Ford Dealers Team in Australia; the team winning both the Australian Touring Car Championship and the Bathurst 1000 endurance race. In later life Smith exercised his interest in racing by running vintage cars. Carroll was an active and avid Society of Automotive Engineers member

 

Never seen a warped rotor....

Must have never looked at a set when they get turned. Cause I've seen plenty of them. Ask any experienced brake person if they have ever seen a warped rotor. I bet most will laugh and say "a few".

And again, you talking about racing setup. Not apples to apples.

 

not sure of a good replacement but just curious as to how long brakes should last? Im riding on stock brakes at 37700 and havent had an issue. How much longer can I expect to have these brakes in good working order?

 

ecl-

That's a bit of a loaded question, & the answer can vary as much as driving habits & geographic location (ie: hills or flatlands) do..

When I rotate my tires, I always check brake pads, brake shoes, & etc..

 

You don't read well do you?

He states

With one qualifier, presuming that the hub and wheel flange are flat and in good condition and that the wheel bolts or hat mounting hardware is in good condition, installed correctly and tightened uniformly and in the correct order to the recommended torque specification,

This means installed properly as warp can accure due to a mechanical issue not heat.

He also states.

In fact every case of "warped brake disc" that I have investigated, whether on a racing car or a street car, has turned out to be friction pad material transferred unevenly to the surface of the disc. This uneven deposition results in thickness variation (TV) or run-out due to hot spotting that occurred at elevated temperatures.

Note he states STREET CAR.

Lets see I have a guy with a HHR with brake issues and claims to warp rotors in an hour or I have a guy that was an trained engineer and many years dealing with brakes of all kinds. Who also has several best sellers that are considered to be Automotive bibles. Not to mention many brake company's that will back up his statments.

Hmm who do I trust.?????

The think the latter as since I have learned the truth I have not had this issue since. Let alone have in happen in an Hour? What were you doing the 24 Hours of Lemons.

Good quality pads with good heat transfer solve most of it and also after a hard stop at the end of an off ramp don't sit there clamp down in one spot on the rotor with it hot. Let it roll up a litte at a time and the pad will not leave a deposit on the rotor.

 

Here is another explanation of what happens to a rotor. THis one is provided by EBC brakes.

3. Brake vibration (rotor shimmying or brake pulsation)
Many good technical articles have been written about this problem which is without doubt the number one regular brake problem encountered. We will give you a short easy to understand recap.

When new brake rotors are installed it is absolutely essential that they run true. All EBC rotors are manufactured and inspected to have less than 0.002 inches (.05mm) of run out. If after your new rotors are installed they have more than this amount of run out, then there is a run out problem on your car. This can be quite easy to resolve and is usually due to one of two things. First the mounting faces where the disc locates on your vehicle must be ABSOLUTELY CLEAN and free from rust or scale which develops during the lifetime of the old rotor. Even the tiniest amount of dirt or scale can throw these run out figures to five times the factory limit. After installing the rotors and tightening them using correct procedures by tightening wheel nuts diagonally with a torque wrench (not an airgun) it is vital to take a few minutes to check rotor run out with a dial gauge and if one of these is not available by holding a screw driver firmly against a part of the caliper body and rotating the disc / rotor to listen or look for distortion. If you do not correct distortion above 0.004 inches (0.1mm) at this point you will DEFINITELY experience brake judder within a few thousand miles. The actual cause of brake judder is not this run out figure (it will be almost impossible for you to detect small run out whilst driving) but over a period of time a “thin spot” would develop on an area of the rotor caused by intermittent pad contact which is known technically as DTV (disc thickness variation). As you apply pedal pressure these thin spots will cause pulsation. If the vibration or shimmying is noticed on the steering wheel it is usually a front rotor problem. The problem is usually only ONE ROTOR not necessarily the pair. If the pulsation is noticed through the bodywork of the car, such as the seat or brake pedal, it is usually a rear rotor that is at fault.

The solution for this vibration is one of two things. 1. either replace the rotors again with new units or 2. take them to your local autoparts store and ask for them to be turned or skimmed. The smallest cut of a few thousandths is all that is needed to correct this problem. When remounting the turned or new rotors, make sure run out is carefully checked as above.

The point at which this thin spot or DTV will occur depends on how regularly or irregularly the brakes are applied. If for example you drive 50 miles to work every day and hardly touch the brakes, it could appear as quickly as 500 miles. The reason for this is that regular use of the brakes tends to wear the whole surface of the brake disc at the same time whereas driving the vehicle “off the brake” causes an intermittent contact between the pad and the high spot on the rotor wearing this high spot down and causing DTV.

The second cause of brake vibration is black spotting of the rotor which is caused by the rotor over heating and a hard spot occurring intermittently around the rotor surface. This in technical terms is the formation of cementite which is a very hard by product of cast iron (rotor material) caused by over heat and sudden cooling. If you witness black spotting the only solution is to replace the rotor or have it turned. Black spotting occurs when the rotor has either worn too thin (having been turned more than once), or by brake pads that are ineffective in balancing rotor and pad temperatures. The problem for the consumer today is that all brake pads looks the same and people rely on the expertise of the guy across the counter who sells them their brakes. The design of brake pad materials is a very exact science and the difference between a company who knows what they’re doing and one who doesn’t is a few percentage points. Brake pads need to have good “thermal conductivity” to take the heat away from the rotor, optimum “compressibility” to allow the brake system to absorb or dampen minor vibrations and optimum “scrub factor”. The latter is the ability of the pad to hone out minor surface imperfections on the rotor as they occur without wearing the rotor excessively. All three of these design criteria and a few hundred more are things that EBC Brakes specialises in. We could ramble on for hours here about how clever we are but the proof of the pudding we say is in the eating. We are confident you will have a great experience with EBC Brakes if you follow our guidelines and should you not find our products to meet your desires, we are an easy company to contact and very service oriented.

This and more tech info can be found at

http://www.ebcbrakes.com/troubleshooting.shtml


Most quality brake companies have very good info available on their web sites. Not just rotor info but other issues. You would be suprised at the truth on many brake issue.

try to follow info from good company web sites as I have found other in accurate into on general web sites.

I hope this helps.

 

You are correct, racing is not a fair comparison. Still, the physics are the same. Your original post says "I was running about 60-65 and had to stand on the brakes. Traffic prevented me from changing lanes. No lockup or anything, but needless to say they got heated up good. After, I noticed a little shimmy in the front on braking.". That to means that you are saying that the one jam on the brakes caused your issue. I say its not possible to generate enough heat in one incident to cause damage, especially warpage. Now I don't doubt that one can ruin a set of rotors in less than 100 miles though. I would think that's pretty easy in fact. But even then I'm not convinced you could truly warp them... unless maybe you rode the brakes constantly and heated the rotors up red hot. However, I will say that the build up of pad material is caused by, or at least accelerated by heat. Heat and cheap pads. And believe me, I've used enough cheap pads over the years. I'm betting that your rotors have what looks like little comet trails on them.

One other thing that may be a factor. I tend to press on my brakes early and glide to a smooth stop. I have to wonder if that could actually be shortening brake life. My pulsating issue started at 9k and again at 20k after the rotors were cut. You went over 40k. So it makes me curious about your braking habits, and everyone elses for that matter. Do you tend to brake hard with short stopping distance, or early with long stopping distance like I do?

 

What's the website?