[jdubm2c]

Hello All,
I installed the AP Racing front kit on my '19 M2C a couple of years ago. A few months later I noticed that the outboard pad/disc face are wearing at a 3x rate to the inside pad/disc face. This issue is present on both front wheels. About a year later I had some suspension work done at my performance shop, and had them buy new discs and re-install the brake kit, but the issue is still there. They reached out to AP, but they have yet to offer any suggestions as to what might be causing the issue. My shop has installed over 100 of these kits on various platforms and has never seen the issue. Has anyone encountered this problem, or have any idea what could be causing it? Thanks.

[OG Shark]

Not uncommon to see a bit of inner/outer pad wear difference on any setup - rotating them about half way through their life is good practice. But 3x is obviously way too much. What calipers are you running?

[jdubm2c]

Originally Posted by OG Shark

Not uncommon to see a bit of inner/outer pad wear difference on any setup - rotating them about half way through their life is good practice. But 3x is obviously way too much. What calipers are you running?

I am running the AP 9660 with Cobalt XR2 pads. I would be fine if it were just the pads since, like you say, I can swap them around and even out the wear. But the outboard sides of the discs are wearing quickly, which is quite a bit of $$ and no workaround for that. I wore out the outside of the discs with 9000 road miles and six track days in one year. Is that normal disc life? If so, I will just deal with the issue. Thanks.

[OG Shark]

Originally Posted by jdubm2c

I am running the AP 9660 with Cobalt XR2 pads. I would be fine if it were just the pads since, like you say, I can swap them around and even out the wear. But the outboard sides of the discs are wearing quickly, which is quite a bit of $$ and no workaround for that. I wore out the outside of the discs with 9000 road miles and six track days in one year. Is that normal disc life? If so, I will just deal with the issue. Thanks.

Ah didn't catch the accelerated disc wear too. Have you had them serviced/rebuilt since they were installed?

[RSXDC5]

AP knows damn well what the issue is. It is a documented issue with their calipers, they flex, not stiff enough, and you get bad pad taper, which leads to already high pad costs now effectively doubling or more in cost. The issue is made worse if you run their anti rattle clips.

Get 2NH (albeit heavy) for a street/track combo or an Alcon BBK through Bimmerworld for race performance

[jritt@essex]

Originally Posted by RSXDC5

AP knows damn well what the issue is. It is a documented issue with their calipers, they flex, not stiff enough, and you get bad pad taper, which leads to already high pad costs now effectively doubling or more in cost. The issue is made worse if you run their anti rattle clips.

Get 2NH (albeit heavy) for a street/track combo or an Alcon BBK through Bimmerworld for race performance

That is complete rubbish, and the Pro5000R Radi-CAL is the stiffest caliper on the market. We have thousands of satisfied owners running them in our brake kits, and there is certainly no 'documented issue' with them: https://www.essexparts.com/news-blog

I'm not sure if you had a poor experience with our product that couldn't be resolved, or what the situation is, but your blanket statement about the quality of AP Racing calipers is both ridiculous and baseless.

Pad taper is a fact of life with any caliper. We see it at every level of racing from every manufacturer. Some conditions promote taper more than others. Please check out our Track and Racing Pad Owner's Guide to get the most out of your brakes, regardless of who made them.

[jritt@essex]

Originally Posted by jdubm2c

Hello All,
I installed the AP Racing front kit on my '19 M2C a couple of years ago. A few months later I noticed that the outboard pad/disc face are wearing at a 3x rate to the inside pad/disc face. This issue is present on both front wheels. About a year later I had some suspension work done at my performance shop, and had them buy new discs and re-install the brake kit, but the issue is still there. They reached out to AP, but they have yet to offer any suggestions as to what might be causing the issue. My shop has installed over 100 of these kits on various platforms and has never seen the issue. Has anyone encountered this problem, or have any idea what could be causing it? Thanks.

Reaching out to AP in England unfortunately isn't going to accomplish anything. If you're running an AP Racing by Essex Kit, it will be our team's responsibility to handle with your shop. I won't speculate as to what the issue is without first having a lot more info in hand. Feel free to PM me and I can find out who worked on your case at Essex. Thanks!

[RSXDC5]

Originally Posted by jritt@essex

That is complete rubbish, and the Pro5000R Radi-CAL is the stiffest caliper on the market. We have thousands of satisfied owners running them in our brake kits, and there is certainly no 'documented issue' with them: https://www.essexparts.com/news-blog

I'm not sure if you had a poor experience with our product that couldn't be resolved, or what the situation is, but your blanket statement about the quality of AP Racing calipers is both ridiculous and baseless.

Pad taper is a fact of life with any caliper. We see it at every level of racing from every manufacturer. Some conditions promote taper more than others. Please check out our Track and Racing Pad Owner's Guide to get the most out of your brakes, regardless of who made them.

So do you deny the excessive pad taper observations that 2x or 3x pad consumption? Do you deny that the anti rattle clips make taper worse? Why does you kit have excessive taper vs other kits?

[jritt@essex]

Originally Posted by jdubm2c

I am running the AP 9660 with Cobalt XR2 pads. I would be fine if it were just the pads since, like you say, I can swap them around and even out the wear. But the outboard sides of the discs are wearing quickly, which is quite a bit of $$ and no workaround for that. I wore out the outside of the discs with 9000 road miles and six track days in one year. Is that normal disc life? If so, I will just deal with the issue. Thanks.

Running around on the street with cold brakes with race pads installed is akin to constantly applying a brake lathe to your discs. Race pads when cold are incredibly abrasive, and the XR2 is one of Cobalt's highest mu compounds. I would absolutely expect them to devour discs when driven 9,000 miles cold on street.

When race pads are hot, they work in an adherent manner and stick to the disc face. When they are cold, they work in an abrasive manner and wear down your discs. That's why the best route is to have a set of road pads for the road, and save your race pads for the track. Yes, you can get away with running some track compounds on the street if they have good manners (some of our customers use Ferodo DS3.12), but there are always tradeoffs with brake pads. There is no magic pad that will do everything well in every environment...simply doesn't exist. Race pads are great on the track but eat discs, are loud, etc. on the street. Street pads are gentle to cold discs on the street, but fade and wear quickly at track temps. There is no pad that does everything well in both arenas.

Our suggestion is using the Ferodo DS2500 for the road/autox/sport driving and the DS1.11 or DS3.12 for track use. All those compounds play nice together on the disc face and work well in their intended environment.

Nobody likes changing pads...I hate to do it on my own cars, but at least our calipers make it much faster and easier than OEM.

Again, you need to use the right pad in the right environment. There is no free lunch with pads and there will always be tradeoffs. This is no different than tires. If you run Hoosiers on the street they aren't going to last very long. If you run 400 treadwear all-seasons on the track, you won't have much grip. It's the exact same dilemma with brake pads. You need to pick the correct tool for the environment.

[jritt@essex]

Originally Posted by RSXDC5

So do you deny the excessive pad taper observations that 2x or 3x pad consumption? Do you deny that the anti rattle clips make taper worse? Why does you kit have excessive taper vs other kits?

You are applying blanket statements based on one person's observations with their car in their situation. Has the sheer number of variables involved escaped you?

Do you deny that just about every person in this discussion likely has different alignment settings? Do you deny that every person here may be running different tires of differing sizes with different inflation pressures? Do you deny that they are possibly on different suspensions, have different driving styles, different power levels, are running on different tracks, for a different number of laps? The list of variables goes on and on...

A mountain of evidence (the thousands of satisfied clients we have, including many on this forum) suggests that there is no inherent problem with our brake kits, calipers, pad tension kits, etc. Every weekend people are out happily winning races and championships on them, HPDE, etc. A quick peek at our blog proves that.

I'll go back to my tire analogy. Does everyone always see the same tire wear? Why did the inner Nitto tire on my Corvette cord early on one side, but not at all on the other side? My buddy's Hoosiers didn't do that. Is it fair for me to now try and publicly crucify Nitto Tire because their tires are inherently flawed?

Have you demonstrated via controlled laboratory testing that our kits have some type of inherent problem? If you haven't, then you're simply making wild accusations and slandering our company and brands.

[RSXDC5]

Originally Posted by jritt@essex

You are applying blanket statements based on one person's observations with their car in their situation. Has the sheer number of variables involved escaped you?

Do you deny that just about every person in this discussion likely has different alignment settings? Do you deny that every person here may be running different tires of differing sizes with different inflation pressures? Do you deny that they are possibly on different suspensions, have different driving styles, different power levels, are running on different tracks, for a different number of laps? The list of variables goes on and on...

A mountain of evidence (the thousands of satisfied clients we have, including many on this forum) suggests that there is no inherent problem with our brake kits, calipers, pad tension kits, etc. Every weekend people are out happily winning races and championships on them, HPDE, etc. A quick peek at our blog proves that.

I'll go back to my tire analogy. Does everyone always see the same tire wear? Why did the inner Nitto tire on my Corvette cord early on one side, but not at all on the other side? My buddy's Hoosiers didn't do that. Is it fair for me to now try and publicly crucify Nitto Tire because their tires are inherently flawed?

Have you demonstrated via controlled laboratory testing that our kits have some type of inherent problem? If you haven't, then you're simply making wild accusations and slandering our company and brands.

You are deflecting. Please answer why your brand’s calipers on the m2/3/4 typically experience extreme pad taper, and why that does not occur on many other calipers when swapped in for comparison.

[FaRKle!]

Originally Posted by RSXDC5

You are deflecting. Please answer why your brand’s calipers on the m2/3/4 typically experience extreme pad taper, and why that does not occur on many other calipers when swapped in for comparison.

"Typically experience extreme pad taper"

Really? I guess my experience must be atypical... I have very very slight pad taper in front. Nothing a simple pad flip/rotation won't fix when I swap between street/track pads anyways.

[RSXDC5]

Originally Posted by FaRKle!

"Typically experience extreme pad taper"

Really? I guess my experience must be atypical... I have very very slight pad taper in front. Nothing a simple pad flip/rotation won't fix when I swap between street/track pads anyways.

For my own internal reference point, what taper do you see and what treadwear tires and pads do you track on?

[jritt@essex]

Originally Posted by RSXDC5

You are deflecting. Please answer why your brand’s calipers on the m2/3/4 typically experience extreme pad taper, and why that does not occur on many other calipers when swapped in for comparison.

Lol. I'm not deflecting anything. I'm straight up telling you that you are full of it.

Below are a just few specific examples of other BMW M owners who don't conform with your conspiracy theory. I guess they didn't get the memo.

https://www.essexparts.com/news-blog...ight-18-wheels

https://www.essexparts.com/news-blog...ing-and-ferodo

https://www.essexparts.com/ap-racing...cs-time-attack

https://www.essexparts.com/video-f80...-racing-brakes

https://www.essexparts.com/video-sup...quipped-e92-m3

https://www.essexparts.com/news-blog...-an-e92-bmw-m3

https://www.essexparts.com/news-blog...s-past-weekend

https://www.essexparts.com/news-blog...-kit-at-a-time

https://www.essexparts.com/news-blog...-at-bimmerfest

https://www.essexparts.com/news-blog...-essex-brakes-

https://www.essexparts.com/news-blog...cing-brake-kit

https://www.essexparts.com/news-blog...-ap-racing-bbk

https://www.essexparts.com/news-blog...ving-technique

https://www.essexparts.com/news-blog...umables-batman

https://www.essexparts.com/news-blog...ical-brake-kit

https://www.essexparts.com/news-blog...arbon-ceramics

https://www.essexparts.com/news-blog...cing-brake-kit


To the OP, I apologize for the detour. Please just PM me and I'll see what I can do to help. Thanks!

[RSXDC5]

Originally Posted by jritt@essex

Lol. I'm not deflecting anything. I'm straight up telling you that you are full of it.

Below are a just few specific examples of other BMW M owners who don't conform with your conspiracy theory. I guess they didn't get the [...]

Lol, as you still deflect from my questions. Ok here you go, this tread has info…

Taper thread

All other variables the same, a non AP BBK swap fixes the issue ^^

Again I will ask, why do these AP calipers have more taper than others? I truly want to know.

When pads can cost $900/set and be gone in a weekend, throwing away pads at half use or less seems like a direct route to double cost pads and a light wallet.

Don’t even get me started on the wear characteristics you have historically had w/ your rotor metallurgy. Swiss cheese comes to mind. There’s a reason the bmw gt4 race teams swapped to Girodisc rotors.

[jdubm2c]

Originally Posted by jritt@essex

Running around on the street with cold brakes with race pads installed is akin to constantly applying a brake lathe to your discs. Race pads when cold are incredibly abrasive, and the XR2 is one of Cobalt's highest mu compounds. I would absolutely expect them to devour discs when driven 9,000 miles cold on street.

When race pads are hot, they work in an adherent manner and stick to the disc face. When they are cold, they work in an abrasive manner and wear down your discs. That's why the best route is to have a set of road pads for the road, and save your race pads for the track. Yes, you can get away with running some track compounds on the street if they have good manners (some of our customers use Ferodo DS3.12), but there are always tradeoffs with brake pads. There is no magic pad that will do everything well in every environment...simply doesn't exist. Race pads are great on the track but eat discs, are loud, etc. on the street. Street pads are gentle to cold discs on the street, but fade and wear quickly at track temps. There is no pad that does everything well in both arenas.

Our suggestion is using the Ferodo DS2500 for the road/autox/sport driving and the DS1.11 or DS3.12 for track use. All those compounds play nice together on the disc face and work well in their intended environment.

Nobody likes changing pads...I hate to do it on my own cars, but at least our calipers make it much faster and easier than OEM.

Again, you need to use the right pad in the right environment. There is no free lunch with pads and there will always be [...]

Thanks for your insight. As I stated, it is not how long the discs lasted, it is that they are wearing 3x faster on the outboard sides, so I end up with worn out outsides and relatively unworn insides. Nobody seems to be able to offer a reason for this. I can only imagine I would get more disc life if the wear was spread more evenly between the outer/inner face. My shop worked with your office. I will get the info and PM you. We were thinking about removing them in Jan. And returning them for evaluation. I do not see any pad taper issue, just the uneven wear. Thanks

[jritt@essex]

Originally Posted by RSXDC5

Lol, as you still deflect from my questions. Ok here you go, this tread has info…

Taper thread

All other variables the same, a non AP BBK swap fixes the issue ^^

Again I will ask, why do these AP calipers have more taper than others? I truly want to know.

When pads can cost $900/set and be gone in a weekend, throwing away pads at half use or less seems like a direct route to double cost pads and a light wallet.

Don’t even get me started on the wear characteristics you have historically had w/ your rotor metallurgy. Swiss cheese comes to mind. There’s a reason the bmw gt4 race teams swapped to Girodisc rotors.

I like how you conveniently posted the link to the page on which there is one primary person complaining. You left out the whole first part of the thread in which there were numerous people chiming in to say that their AP Racing by Essex Brake Kit was performing great, that we offer excellent support, that it was easy to get the right pad shapes, etc. If anyone wants to read that post, they should read from the beginning. Keep in mind that there are a LOT of experts on the internet!

https://www.m3post.com/forums/showthread.php?t=1907146

"Again I will ask, why do these AP calipers have more taper than others? I truly want to know."

Again, one person's experience in a completely uncontrolled environment is simply that. I don't know what else you want to hear about that.

As for a team switching to Girodiscs...did it ever occur to you that there might be some type of commercial agreement involved? Girodisc has been trying to get their product on professional racecars for years to add to their street cred. We see that sort of thing at all levels of the sport. In NASCAR Cup in the years leading up to the switch to the current Next Gen Car, Raybestos/Alcon gave millions of dollars worth of free brake products to various teams in an attempt to gain market share. Another example would be the recent the Le Mans-winning Porsche 911 RSR that runs AP Racing Radi-CAL calipers. They sometimes pair them with Brembo Discs as shown in the photo below. Brembo owns AP Racing, and both companies both certainly like the exposure that accompanies a Le Mans win. Oh, and BTW, after winning Le Mans, Porsche didn't report any abnormal taper wear on their fundamentally flawed and flexible rear AP Radi-CAL calipers.

[jritt@essex]

Originally Posted by jdubm2c

Thanks for your insight. As I stated, it is not how long the discs lasted, it is that they are wearing 3x faster on the outboard sides, so I end up with worn out outsides and relatively unworn insides. Nobody seems to be able to offer a reason for this. I can only imagine I would get more disc life if the wear was spread more evenly between the outer/inner face. My shop worked with your office. I will get the info and PM you. We were thinking about removing them in Jan. And returning them for evaluation. I do not see any pad taper issue, just the uneven wear. Thanks

10-4. Just shoot me the info and I will make sure it gets addressed. Thanks!

[///MPhatic]

Originally Posted by RSXDC5

You are deflecting. Please answer why your brand’s calipers on the m2/3/4 typically experience extreme pad taper, and why that does not occur on many other calipers when swapped in for comparison.

He's not deflecting, he doesn't agree with what you're saying, and doesn't have an answer to the problem, but has agreed to look into it, which is all anyone can expect.

[jritt@essex]

Also of note, just yesterday BMW Motorsport posted on Facebook about one of their M4 GT4 customer cars being on the podium in all three races of its debut weekend in the GT Winter Series. Guess what brakes they've been using...AP Racing Radi-CALs and J Hook discs.

https://www.facebook.com/BMWMotorspo...RRCC2Yx3F9wZYl

[rbahr]

Problem is heat (I suspect ) for some reason the outside - closest to the wheel is running much hotter than the inside.

Ray

[Fabb]

Could be installation issue. Did you measure the rotor is at the true center of the caliper? My ap kit has been flawless, but the previous owner had taper wear, which turned out that the shop installed the caliper at the wrong side.