Brake rotor question

[Hirkophoto]

I have a 2006 SRT10 with the Stop tech ACR rotors on the car. Brake calipers are standard, pads are EBC green. My rotors seem to be wearing in an odd way. Toward the center of the rotor I'm getting a grove that is wearing into the rotor. It's happening on both sides of the rotor and both sides of the car in the front. Has anyone else seen this before? I inspected the pads and can see the opposite bump on the pad. Which can easily be scraped off with a screw driver. So it seems its there only because of the rotor groove? My freind has an ACR and we see a faint line on his rotors but not grooved like mine. The only thing we could come up with is the dust is being forced down the slots in the rotor and is accumulating at the bottom and building up there. Seems like that should not cause it but.....

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[bluesrt]

try a differant pad

 

[FrgMstr]

What do the pad look like? Any signs of odd wear there?

 

[bluesrt]

rectangulaur in shape usually, about 5 x 3 in size

 

[steve911]

I run Brembo's one piece slotted rotors and do not have that problem. I use stock or porterfield pads depending upon what I am doing with the car.

 

[Hirkophoto]

Pads have the same bump on them from the groove in the rotor. Like I said you can just scrape it off. So I believe its there from the rotor. in other words there does not seem to be anything there that is causing the groove. Pads seem to be wearing normally.

 

[bluesrt]

my crystal ball says put all new stuff on, switch style of brake pads, if still does it, just drive it and forget about it

 

[Hirkophoto]

Yep, already thought to just drive it at this point. Just want to see if anyone else had seen this?

 

[bluesrt]

i have seen this before a million times, usually its in the pads... , if their is a groove in the rotor, its from the pads or hardware

 

[Hirkophoto]

Now it's a million and one times

 

[bluesrt]

lolzzzz........

 

[FrgMstr]

Might send the pic to StopTech as well and see if they have any crystal ball insight.

Looks like new rotors and pads are needed though. I don't think you are going to stop that from wearing more in that same spot though and that is one hell of a groove.

 

[steve911]

I wont be so quick to say that new rotors are needed. New pads? definitely IMHO. The location of the groove is far below the "main" brake pad contact area of the rotor. Additionally its been my experience that the grooves/ slots that are machined into the rotors, only extend to the minimum operational thickness dimension of the rotor, so theoretically you can run the rotor until the grooves disappear.

It looks like the groove in the rotor doesn't equal the depth of the slots. Were it me I would run it till it wore out.

 

[JonB]

I suspect pad issue. You say EBC Greens? OLD? as in 2006 era Kevlar? Greens were reformulated in 2007, and "not as good" after that, So I suspect a non-homogenous pad compound. A "Pad Problem" that will get worse, and must be watched.

If you change pads alone, re-surface the rotors or you will transfer the rotor low spot to the new pad as a high spot, and continue the issue....

Good that you noticed...............

 

[AZTVR]

Now it's a million and one times

A million and two. I have StopTech calipers and rotors and they look EXACTLY the same. (same groove worn at the same location in relation to the end of the straight groove) I was just wondering this weekend what the cause could be as I was checking my pads after my last event.

 

[Sonoman]

I don't think it's a coincidence that the worn groove is at the end of the machined groove. Channeling of abrasive debris is building up at that point and wearing the rotors. Have them cross-drilled an the problem will go away. Kidding, but it would be nice if Stop-Tech would address this little issue, maybe if enough people complained...

 

[bluesrt]

I don't think it's a coincidence that the worn groove is at the end of the machined groove. Channeling of abrasive debris is building up at that point and wearing the rotors. Have them cross-drilled an the problem will go away. Kidding, but it would be nice if Stop-Tech would address this little issue, maybe if enough people complained...

good luck, only in a normal world that would happen

 

[mjorgensen Woodhouse]

I wont be so quick to say that new rotors are needed. New pads? definitely IMHO. The location of the groove is far below the "main" brake pad contact area of the rotor. Additionally its been my experience that the grooves/ slots that are machined into the rotors, only extend to the minimum operational thickness dimension of the rotor, so theoretically you can run the rotor until the grooves disappear.

It looks like the groove in the rotor doesn't equal the depth of the slots. Were it me I would run it till it wore out.

Yup ^^^ I would to

 

[bluesrt]

dont know if i would do that as to i like all the metal on a rotor i can get for its desighn, maybe on a ******,yes, but a dodge viper- im thinkin throw em away and get new if they are close to the cut marks dissapearing. unless you are city sunday driveing, and in that case why have a high dollar rotor on there.? run a stock cheap one and ditch them when you replace the pads

 

[mjorgensen Woodhouse]

As the slots themselves wear down so will the deposits and the face will catch up to the "groove" been here done that.

dont know if i would do that as to i like all the metal on a rotor i can get for its desighn, maybe on a ******,yes, but a dodge viper- im thinkin throw em away and get new if they are close to the cut marks dissapearing. unless you are city sunday driveing, and in that case why have a high dollar rotor on there.? run a stock cheap one and ditch them when you replace the pads

 

[bluesrt]

exactly....... i hear ya

 

[Viper X]

Scott,

Not a fan of EBC pads personally as Jon B says, they changed the composition of their brake pads a while back. Porterfield R4's up front and OE pads in the back work well as a street / track combo.

Clean up the surface of the rotors by scuffing them with sandpaper or scotch brite pads, then install new brake pads and bed them per the makers instructions.

There are quite a few better, more aggressive pads for the front if you are going to the track but they will be pretty dusty and squeaky as street pads.

Dan

 

[Hirkophoto]

As the slots themselves wear down so will the deposits and the face will catch up to the "groove" been here done that.

Thanks for all the replys. There seems to be some differing of opinions as always. I have to correct my post. I actually have green pads (the backing plate) but after closer inspection I think they may be brake man pads. It's very hard to make out any writing. Anyway. it does not seen to be effecting anything at this point. I'm not going to replace them since they only have low miles on them. The slots wearing down and that evening out on the groove seems to make sense to me.

 

[Hirkophoto]

Scott,

Not a fan of EBC pads personally as Jon B says, they changed the composition of their brake pads a while back. Porterfield R4's up front and OE pads in the back work well as a street / track combo.

Clean up the surface of the rotors by scuffing them with sandpaper or scotch brite pads, then install new brake pads and bed them per the makers instructions.

There are quite a few better, more aggressive pads for the front if you are going to the track but they will be pretty dusty and squeaky as street pads.

Dan

Dan, Are you seeing wear like this as well? I have to check your brakes next time I see you. Now I'm going to start looking at all the ACR rotors. I'm also going to take some better pictures and send them to Stoptech to see what they say.

 

[Hirkophoto]

Here is info straight from Stoptech:
"This is a result of the pad you are using running predominantly too cold for the friction material type and your driving profile. Almost all pads are more abrasive when cold and in this case the Aerorotor hat is keeping the inner edge of the pad too cold and the pad on that inner edge is wearing down the rotor. In a racing context we would tell the team to block off some of the brake ducts or choose another friction formula. In your case the latter makes the most sense. There is no hazard here only the aesthetic result so please do not worry."
So at least I know what causes it and what needs to be done to fix it.

 

[Camfab]

That sounds good except your pic shows the same exact event occuring at the trailing edge of the slot. Truthfully your initial guess sounds much more logical to me, but hey what do I know. I'd be curious to know how many miles are on those rotors and pads. Were they installed at the same time? I'd love a set of those, but they are too rich for my blood.

 

[Hirkophoto]

I think what he is saying is, that part of the pad is not heating up. I sent him extensive photos so he did mean where the groove was happening. The good news is there is no need to do anything if I want to leave it.

 

[FrgMstr]

Here is info straight from Stoptech:
"This is a result of the pad you are using running predominantly too cold for the friction material type and your driving profile. Almost all pads are more abrasive when cold and in this case the Aerorotor hat is keeping the inner edge of the pad too cold and the pad on that inner edge is wearing down the rotor. In a racing context we would tell the team to block off some of the brake ducts or choose another friction formula. In your case the latter makes the most sense. There is no hazard here only the aesthetic result so please do not worry."
So at least I know what causes it and what needs to be done to fix it.

Thanks for the followup, good to get educated from the source.

 

[ViperGeorge]

I will admit to being a little confused by the picture and Stoptech's response. Am I correct that the wear in the rotor is virtually as wide as the pad? That's the way it looks to me in the picture although I admit I do not have my reading glasses on. If it is nearly as wide as the pad then I would say that you are using too aggressive a pad and it is simply wearing out the rotor. Not unusual for certain pads. Some are pads are not rotor friendly. I don't see how Stoptech's response addresses the wear that I think I see in the picture.

I suppose the shape of the pad could be contributing to the nature of the wear as well. I'd have to check my pads but my guess is that the rotor is subject to slight differences in the size of the pad area that contacts the rotor along its diameter. This could lead to somewhat different wear at the edges of the pad, if as I suspect, there is less contact with pad at the edge. Until I check my car though that's a guess.