So..., I was excited for a couple minutes, thinking there was a place in town that took care of Alcons, so maybe I should shop for a car with them.
But the second link with the address, shows it’s just a house in a residential neighborhood. Some guy selling kits out of his basement or garage! Cancelled my shopping plans...

 

Well im sure somewhere somebody did something where they ended up with a warped rotor but I wonder if maybe it hit something and was bent more than warped. Or maybe counterfeit rotors made from pot metal.

all I know is ive driven high powered muscle cars all my life. My first car was a dodge challenger and the second a cuda and now a hellcat. I drive the wheels off all of them and have taken them to the brink of destruction and yet ive never seen one warped.

Bent one? Maybe? worn irregularly?? Sure! All the time. Heated them till thd were blue, crazed snd cracked? Sure! But thats not warp. And im looking for them to warp and sure they will pulse after a while. But I fix pulsating brakes that arent cracked either by bedding the brakes or using a drill mounted brake hone which looks like a wire wheel brush from a drill with little ***** on the ends that take off small imperfections, glaze and gives a great like new machined crosshatched high fiction surface.

I run my brakes hard. I really abuse them. I should see warpage all the time. But I dont and I use oreilly brake best. Crap, wagner crap. AC Delco. Basically anything except generic no name ****. That why I dont believe brakes warp. And ive been driving since I was 14 back in ‘ 77. Thats a shitton of miles. But im sure it can happen. I just have to believe it was rare though or a **** poor install or a caliper or bracket was bad causing uneven wear that pulsed.

now if the rotor hat went on, wasnt seated or wasnt flush to the hub it will wear funny and probably pulse and that needs machining to fix because it wore the rotor unevenly

did you ever watch brakes get turned? The always seem to have a single period like a high side and a low side. Not a potato shape or multiple dips and bumps. Idk. Maybe cheap chinese counterfeits caused it.

Btw cast iron pans do warp but they arent anything like disks. Cast iron pans are thin walled, cheap cast iron made in a sand mold the sit on a hot stove burner directly contacting the entire bottom of the pan for long periods of time- 10 20, 30 minutes or more. A rotor gets part of it heated where the brake pad touched and then it spins into forced cooling air for may 20 second or a minute at most. Cast iron pans are CAST. Not forged, stress relieved or machined nor do cast iron pans have the structural integrity that the boxed ventilated thick disk does. The reason theres a minimum thickness is because bad things can happen when the rotors too thin! as the faces wear down theres a less metal to dissipate the heat so you get really holt and then you get brake fade. the rotor metal overheats bc its thinner and cant dissipate the heat as well. Then turns colors, gets all polished so the brakes work poor and then you get crazing and cracks and DANGER. That rotor boxlike structure is strong as hell to resist bending. But you can overheat them and crack them and its easier when the rotors are worn down and grooved and thats when stress cracks start coming . Also when they are too thin, you can run the risk of pushing a piston out too far, or cooking the seals from the heat which causes the pistonseals to harden, brake fluid to boil and bake so its viscosity changes. The caliper piston jams or sticks or leak brake fluid. Thats why there a minimum thickness.

If you work on your own car, try the brake bedding trick. It costs nothing. And I really recommend a brake hone! I just recently got this hone but ive used it several times and its amazing. Just have to use it right at the correct steady rpm as the rotor rotates. And it cheap. Try it!!

hasta

 

Never seen that tool, thanks for mentioning. Definitely would be worth a try.

 

I thought I uploaded a pic of it but I guess I didnt. Here it is.

 

Well.... Lots of speculation here. A local Jag friend of mine pointed me to this thread. Lets start by setting aside some misinformation about Alconkits.

1. It is not "run out of someones basement." We have a rather large co-located warehouse in Edwards IL. I own the holding company MotoDelta and several automotive business. Alconkits is a brand. You might recognize Edwards/Peoria as the home of Hoerr Racing Products. We rent warehouse space from them rather than building and operating our own. Good business sense. I've known that family for 20 years. Good people. Any doubts - call them and ask.
2. We aren't "Alcon UK" We are, however, the largest Alcon dealer in the US. Any doubts? Call Alcon's US headquarters and ask them.
3. The D&B information is quite wrong. ...but our revenue isn't anyone's business.

There - now we've established some business legitimacy.

So onto some braking knowledge.

Can you warp a rotor? Sure. I've seen about 2-3 in 20 years. It is VERY unlikely and only happens with cheaply made thin rotors. However what is "warp"? Most mechanics would put a dial indicator on the rotor, turn it, and see high and low indications and conclude it's warped. However they are wrong.

What they ARE seeing is high and low spots on the rotor caused by uneven wear across the braking surface. When pads are not properly bedded there are areas of high and low friction on the rotor. At that point as the pads sweep across that surface, the areas of high friction will wear faster than the areas of low friction. THose areas wear faster and read as low spots. The areas of low friction eventually build up something called cementite that continues to build and get worse and higher.

So the rotors are not warped or bent - they are WORN UNEVENLY.
.
(...and by the way - we do offer full Alcon caliper servicing in our Edwards location. Disassembly, cleaning, rebuild, and pressure testing. ...or you can go to your dealer for this. Naturally they'll end up ordering the seals from us most of the time as I'm 1 of 2 places in the US that stock them)

Here is one of our happy Jag customers: https://www.jaguarforums.com/forum/x...ebuild-211174/

 

Uhhh... No. https://www.zoominfo.com/c/alcon-kits/359220922

Additionally our "flawed reference material" has been cited in a number of academic journals, wikipedia, and other vetted sources. I know because I wrote it.

 

So first of all MotoDelta is a holding company under which we run several businesses. Alconkits warehouse is in Edwards, IL co-located with Hoerr Racing Products.

We do plenty of Jaguar rebuilds and are one of maybe two places in the US that stock seals, pistons, etc.. and are trained and qualified to refurbish Alcon calipers.

Lastly - rotors don't warp. What they CAN do is develop high and low spots due to improper/bad pad bedding where low friction areas get hot and build cementite. High friction areas wear faster. Your mechanic reads this as warped - but the rotor itself is straight, but the surface is worn unevenly. Sure you can probably find a few cheap chinese made rotors as anecdotal evidence that they do - but thats so rare of the 10,000 rotors we've seen - I've seen 2-3 maybe that I would say were actually BENT/WARPED.

Once you understand the metallurgy and how braking works (Abrasive and adherent friction, etc..) the idea that rotors warp suddenly seems absurd. However we FREQUENTLY see rotors that weren't bedded well - or that bedding was damaged (rust, pad swaps, etc.) that develop high and low spots and create a pedal shudder under braking. That is very common in performance brake systems that aren't maintained/managed well.

...as for the gentleman that suggested our articles and published knowledge is "flawed". Many automotive academic citations about my work as well as wikipedia references and professional race teams would disagree with your assessment on what I know about braking.

For example: https://www.researchgate.net/publica...e_Brake_System we are cited here.

One does not need to have some shiny glass building to know ones sh*t.

 

Define "Warped"....
Uneven, wavy, misfigured.
i.e. "My rotors got uneven, wavy and misfigured due to develop(ed) high and low spots due to improper/bad pad bedding where low friction areas get hot and build cementite.".
Also known as 'warped'.

 

I’m to assume this is Chris. Glad to have you here to defend science and also participate in these forums. What some here may not realise, Alcon are one of the major brake manufacturers in professional racing and fitted to many, many cars such as Nissan, McLaren, Aston Martin, etc. So when there are so few specialists, you can be certain they do a fair bit of business.

I don’t have it at the moment but there’s also a representative from Alcon on one of the UK forums explaining the confusion of “warped” rotors and explains it like everyone else who knows, it’s pad bedding flaws, uneven pad material, etc.

 

According to the Oxford English dictionary:

"warp, verb -

Make or become bent or twisted out of shape, typically as a result of the effects of heat or damp"

So "warped" means bent or twisted out of shape, which IMHO does NOT accurately describe brake discs which have high/low spots due to uneven brake pad material deposition.
Put another way, I don't think "warped" means what you (and many others) think it means.

 

I think it refers to the nut behind the wheel.

 

Awesome Alconguy! Thank you for your input! I trust you and I believe you. That being said when I first read these articles about material transfer and the myth of warped brake rotors I was skeptical. But knowing that I don’t know everything in the world I decided to test the theory and sure enough in every situation where I have had that brake shudder I would rebed the brakes according to the procedures stated with several heavy braking in rapid succession at different speeds and baking force followed by a long cool off And lo and behold no more brake shudder.

So there- the theory was put to test and proven out. In fact since the day I learned this I never had another case of warped rotors in my life.

 

Hey alconguy, whats your opinion on these brake rotor hones. I spin the rotor as I hone it with a drill set to the stated speed and I get a beautiful pattern on the rotor. Seems like it works but I figured id ask an expert

 

OK, I am not such to refuse to apologize when I am wrong, you look to be a reputable company and what I saw originally led me to think you were some scratcher **** house on the internet. So sorry for that.

First, your article on your site regarding warp has absolutely no science that I can see, just your empirical data. Which is vast which I get, but I will stick to my guns that nobody has provided me science and I find that to be flawed because it is all opinion pieces. The article that you point to where you guys are used as a reference is a scientific study but was regarding Brake Fade, what does that have to do with our discussion here other than you are looking to establish bona fide's. It is a nicely written piece by a Nigerian published in a Ukranian journal. Please provide me a similar study into rotor warp. These guys on here are stating absolutes, that there can NEVER be warpage. Yet you very nicely pointed out that you have seen it, albeit a very small sampling of a much larger group. But it has happened.

Whoa whoa whoa fella's, what did he just say???

 

Is the world flat or is it round , off course its round lol but listening to ceejay it's flat , guys a troll offers no more advice other than battery's , wise up guys , discs don't warp end of story

 

Wow, 74 posts and still going! The end is in sight!

 

Yes empirical data means a lot. Experience means a lot. More than any textbook. What benefit is it to brake manufacturers to defend the “myth” of warped rotors? Like the chain store brake specialists which rely on perpetuating this myth to sell profitable parts and labour, wouldn’t it be beneficial for them to sell more rotors and pads?

 

Well, post #66 admitted that it can happen, rare, but it can.

 

Never mind, not worth the effort.

 

Yes he said he saw 2 or 3 rotors that were warped but out of how many? Hundreds? Thousands? 10s of thousands? And he didnt say why so it could have been from impact damage!

long story short. Most of the brake shudder is from the transfer of pad material. Not all of us are saying its always one thing. I specifically tried to state the cause is most likely.

and as someone else said, if brake warping from heat were more common, the manufacturers would love it because they could sell more rotors. And it wouldnt be a manufacturing defect under warranty due it being caused by the driver overheating the brakes.

just try re-bedding the pads when your brakes shudder. Hone the rotor with the hone I posted. Youll see if its physically warped or not