Ok since its brakes it's way important.
There's been lots of recent posts about rotor warping.

So what is the common thread?
Is it milage? Continued hard braking? Or something as innocuous as using a car wash with the rotors sizzling from some driving.

Lets see if there's a way to put the brakes on this problem.

As for me, I've been lucky. I've had no rotor/braking glitches. I'm at 15k miles, drive hard but never have many panic stops and never have the rotors get wet while they are hot. I think that saying that rain on hot rotors is the same as getting the car washed while the rotors are hot is different. First off I don't know of to many folks who heat the brakes real hot while driving in the rain. And driving in the rain I would think allows cooling more gently than a splash of cold water.

So what is causing the rotors to warp?

Ideas?
Trends?
Personal statistics on braking.

Thanks

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"01" CL Type-S
White\Black
Comptech Springs
Comptech Sways
17x7.5 BBS RX Rims
K&N Dropin AF
Navigation System
Burlwood Shifter
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PIAA16969
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My Car
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I was told that Acura originally used brake pads with too much metallic content and this was warping the rotors. I had my rotors resurfaced and got new brake pads, this stopped any vibrations I felt on my steering wheel.

 

Here's my thread about over tightened wheels causing warped rotors.

http://www.acura-cl.com/ubb/Forum1/HTML/006339.html

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'01 CLS #4055 Red/Parchment-all the goodies

 

Ok it's an idea. But do you mean that Acura used a too high metallic content pad on 01 and greater CL/TL's? And your new brake pads, were they installed from your dealerships stock?

Thanks

------------------
"01" CL Type-S
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17x7.5 BBS RX Rims
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Dave
That listens. When I got my wheels (Satin wherever you are I luv ya) the installer had me come back after the first 100 miles to retorque them. Made me feel funny but maybe new tire bolts "break in" or something. I'm an idjit because I should of asked him why he does that? Satin?



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"01" CL Type-S
White\Black
Comptech Springs
Comptech Sways
17x7.5 BBS RX Rims
K&N Dropin AF
Navigation System
Burlwood Shifter
Guards+Fenderwell Trim
PIAA16969
Smokers Package
DOM 5/00 #9177
My Car
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I think it's due to the fact that the car is just under-brake'd (gee, that doesn't sound as good as under-tire'd )

But seriously, we have a 3500+lb luxo cruiser and Acura obviously didn't try to win any contests with their braking system. Most reviews have rated them either acceptable or slightly weak. I think this causes the brakes to be more susceptible to problems than say, our engine.

 

Well I don't know on what models the brake pads contained too high of a metallic content, but that's what I was told about my CL-S. And yes, the pads were replaced with pads from the dealer's stock, but they said that these were different pads from the ones originally on the car. They said that these pads shouldn't give me any problems because I asked if this was a hassle I was going to have to go through every couple thousand miles. They said that it isn't a temporary fix, so resurfacing the rotors would suffice, since I had asked why I couldn't just get new rotors. I guess time will tell if it actually worked. I don't know if this is BS they gave me, but that's what I was told.

I also thought that it might be due to the overtightening of the wheels since it had been mentioned on the board before. My steering wheel didn't start vibratring until about a week after I had my tires rotated so maybe the people at Esserman Acura ovetightened my wheels. Honestly, I wouldn't doubt it b/c that place really sucks. I just took my car there for an oil change and to get the tires rotated since Rick Case is about an hour away from me.

 

Today I noticed the mentioned vibration in my car when slowing down from about 75 or 80.
I don't consider myself a "brake abuser" by any means and only once have I had to slam on the brakes to avoid another car crash into me. So I don't know what causes this problem but I sure hope it's covered by the warranty.

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2001 Silver CL-S

 

Yes, everything was under warranty.

 

I noticed in my CL-S a small vibration when I brake at 75-80 MPH when I had 5500 miles on my car. I am now at 7700 and it is a little more noticable. I was very easy on the brakes when I first got the car. I was able to not brake hard at all for the first 600-700 miles. I have had 3 panic stops since I've had the car, 2 of which ABS'ed on drive pavement. I do not race my car, it's never been to a track and I'm generally easy on the car. I am also very aware of not putting cold water on warm rotors. I can't say I haven't hit a puddle or 2, but I'm very aware of this. One last thing, I have not had the rims removed since I bought it, so unless they took the wheels off at my 3500 service, it's not due to a bolt torque problem.

I'm about to bring it in for the 7500 service, you guys say it's under warranty to have the brakes turned, or replaced? I'd imagine having to pay for the break pads, but what about the rotors?

DC

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2001 CL-S red, spoiler, mud guards, moon visor

[This message has been edited by Handruin (edited 06-21-2001).]

 

At 20k miles on my CLS the braking vibration was so bad I had them true the rotors (under warranty). The discouraging part about my car is that it has done very little braking in that 20k miles. I use the car primarily on a straight 35 mile commute with the cruise set at 80 mph. Of that 35 miles less than 4 miles of it do I acutally touch the brakes. Maybe it's the braking from high speed, but I don't see how that can be because 99.9 percent of the time that is very tame. Anyway . . ... I agree the brakes are a weak point!

 

I'd sure like to hear more about the "magic" pad issue.

Normally, a metallic pad will help conduct heat away from the rotors. In the "old days", metallic pads that were too hard, would not warp the disks, but would groove the disks from their hard composition. The pressure of application would cause the "hard" material to form low points in the disks.

I had used some metallic pads on my other car with fading problems (fluid upgrade and pad upgrade). The fading was reduced, and I went with semi-metallic pads. These pads had much more metal than the stock pads. The metallic pads were rough on the rotors, but the rotors didn't warp and the fade was reduced and the stopping power was enhanced.

So, where can we get more info about this new mystery?


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Silver 2001 CL-S with NAVI

• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (50 lbs less than stock)
• Comptech headers & sways
• Silver AEM CAI
• 12 coats of Zaino magic
• Stainless Brake lines coming (Brembos?)
• V1 planned

 

it's not the tire bolts that are the problem as they are part of the hub and don't get changed...
it's because your new rims will squish a little but once they have been tightened down so a re-torrquing is necessary to ensure your wheel doesn't fall off while you're driving...



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Astroboy out...

2001 Acura CL Type S: Comptech: Headers, filter, sways, springs, koni shocks, Volk Racing SE37's in 18", goodridge braided brake lines, AEM CAI (blue), APEXi V-AFC, full kicker system, 13" Brembo's on the way with slotted discs for the rear
1996 Porsche 911 Twin Turbo: H&R Springs and sways, Bilstein shocks, ported and polished, crillo rods, new valvetrain
1995 VW Golf: 1999 VR6 Swap, H&R Coil Overs, neuspeed strut bars, neuspeed sway bars, 2.5" Stainless TT exhaust w/ Borla, 13" AP Racing big brakes

 

I haven't heard anything myself. This link shows service bulletins that are known about the car. Nothing for the 2001 yet.

http://www.alldata.com/recall/make

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'98 Black 3.0 CL
Currently --
Tint, Fog lights, Clear corners, TL rear lettering, factory spoiler.

 

Ok. Good data sharing here. Seems the brakes (rotors) problem is not so isolated. The problem mainly is witnessed when braking (not necessarily panic braking) from about 70 - 80 mph. The amount of resistance necessary at this speed might be sufficient enough to cause whatever it is that is causing this to begin. But what is the ORIGIN? Pads, warped rotors, both, or as Golden said, the stopping of such a heavy car with the current OEM brake system? Are not other cars of this weight suspectable to this problem?

Has anybody with this problem NEVER had their very warm rotors splashed by cold water? Have any of you with this problem ever washed the brakes after they are warmed?

Have any with this problem had new rims installed without having the torqueing checked soon after? Have any of you with this had your wheels removed for any reason and replaced without checking the torque soon after mounting?

Thank you

------------------
"01" CL Type-S
White\Black
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Comptech Sways
17x7.5 BBS RX Rims
K&N Dropin AF
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DOM 5/00 #9177
My Car
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My 2001 CL-P has the same problem at 15k miles. I also noticed it on the 99 Honda EX V6 Coupe and 95 Honda Coupe. I think it might have to do with sustained high speed (relatively) driving.
Like some of the other posts, I do primarily highway driving with minimal braking.

It could be that maintaining 80mph+ or so on a regular basis generates enough heat to warp the rotors slightly.

It is very subtle, but you can feel it during low speed braking, not so much as a vibration, but as a pulsing in the brakes.

I think Honda/Acura must be using inferior metals in their rotors. (Or I'm exceeding the design specs)

IMHO,

TF33
2001 CL-P

 

Would just an excess amount of heat cause warping? I don't regularly exceed 80mph+ for long distances except on road trips but I do have the problem of it being 100+ for 6 mos out of the year. I'm sure my brakes get pretty damn hot out here!


Question:
How long does it take brakes to cool off? I came back to Phoenix from Tucson the other day. It was 105 degrees and that was a 120 mile trip. I washed my car about 3 hours after getting home. Because of the heat, the car was still pretty warm, but I could at least touch the rotors without burning myself. Do they need to be totally cooled off to avoid warping or just cooled down?

 

I don't intend to live with this problem. I love the car and this is somewhat disapointing. I am going to take it to the dealer and see what happens. I never did anything with the Honda that I had previously. My driving habbits are consistent and I put the miles on fairly quickly. Unfortunately, I haven't washed my car often enough to know if the temp swing is causing the problem (cool water on hot rotors).
On airplane disc brakes (after an aborted takeoff) the max effect of the temperature is not reached until 15 minutes after braking, and then the tires explode - sad to say i know more about airplane brakes - but i digress...

I think the problem is coming from the rotors. If anyone finds anything conclusive, let me know.

TF33
2001 CLP

 

if you're talking about airliners, I would think this effect relates to the caliper/pad combination covering a significantly larger proportion of the rotor swept area (up to 100 percent in some cases) than they do on typical automotive applications.

 

You are correct about the calipers/carbon brakes. I think the brake energy required to stop increases exponentially with speed. I believe this would hold true for cars as well. Or I could be wrong...

TF33
2001 CLP Silver / No Thrust Reversers

 

The energy from a moving car is kinetic energy and it is represented by:

Mass * Velocity^2 = Kinetic Energy.

E = mv^2 (just like mc^2 )

The Velocity is squared, so the energy goes up by the square of the velocity.

A car stopping from 40 MPH will need to dissipate 4 times the energy as a car stopping from 20 MPH

Airplanes have anti-lock brakes and a number of them have thrust reversers. Jets had the first anti-lock systems -- and these were used for wet and icy runways. The carbon brakes (as used on airplanes and F1 cars) have very high melting points, very low thermal conductivity, and very low bulk thermal storage. However, an airplane and F1 car do have high speeds in common -- this allows the red-hot brakes to cool very quickly due to the very high air flow used to cool brakes. Having low thermal mass, they cool down rather quickly. Radiant heat is transferred according to a 4th power equation.

Unfortunately, our cars don't typically run at 100+ MPH, and don't have ducted brakes. So, the thermal model applicable to F1 cars and jets isn't applicable to our cars (as commonly used).



------------------
Silver 2001 CL-S with NAVI

• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (50 lbs less than stock)
• Comptech headers & sways
• Silver AEM CAI
• 12 coats of Zaino magic
• NEUSPEED Upper Strut Tie Bar ordered
• Stainless Brake lines coming (Brembos?)
• V1 planned

 

One thing I want to know is, at what point does the dealer say it's your fault/normal wear and tear vs. covered under warranty?

I have the problem now, but I'm at 20k miles (mostly highway). I had one incident of hard braking because some idiot turned left in front of me. I'm about to go in for service and I need a re-surfacing to fix it, but don't know if they'll pay for it.

I'm guessing it depends on the dealer?


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01 Silver CL-S, Navi, Spoiler, V1, PIAA's
Retired: 94 540i

 

how can u tell if ur brake rotors are warped? sorry i'm automotive illiterate...

 

Well.... Generally speaking, if you press the brakes and feel the steering wheel wobble, I would call that a "positive."

If you balance the wheels/tires and you get a bit of vibration in the wheel, this COULD be a "positive."

When the rotors warp, they are no longer nice and "smooth". Your brake pedal causes a couple of brake pads to squeeze the disk/rotor -- if it is warped (Imagine an old vinyl record that got left out in the sun) it will make for tons of vibration and/or wobbling in the suspension and in the steering.

Since our cars are so front-heavy, the effects will be noticed in the front, rather than the rear (at least the bulk of the time).


------------------
Silver 2001 CL-S with NAVI

• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (50 lbs less than stock)
• Comptech headers & sways
• Silver AEM CAI
• 12 coats of Zaino magic
• NEUSPEED Upper Strut Tie Bar ordered
• Stainless Brake lines coming (Brembos?)
• V1 planned

[This message has been edited by EricL (edited 06-25-2001).]