Pad Rotor Problem AP Disks

[CSG Mike]

Originally Posted by Dezoris

I'll get a picture of the 1521s they were not groves more totally uneven accross the entire surface. You can feel it with our fingers too. Very wavy.

THat's HIGHLY unusual for the 1521. I'd speculate that the grooves on the rotors were there from a race pad, and the 1521 molded to that shape...

The 1521 isn't abrasive enough to do that unless you cook em badly.

[Dave-ROR]

Originally Posted by acro

Do the AP Racing S100 pads work well and not make noise? Any one know their temperature range?

Work fine. Make noise.

[JRitt]

I'm still here! But yes, I am trying to sell M3 kits too! You guys can't hoard all the good sh*t!

[Dave-ROR]

Stay away from my M3!

:moneyburn:

[dradernh]

Originally Posted by CSG Mike

Grooves that run radially are normal...

In my case, depth/shape-wise, I had a single radial dimple, with the low spot on the rotor and the high spot on the pad. I experienced no reduction in performance from this anomaly, as described here:
http://www.essexpartsblog.com/news/c...acing-comp-bbk

I was not, however, swapping pads nor pad compounds on the same rotor. I wouldn't have had a problem putting on a fresh pad, but would not have put the used pad on a fresh rotor.

[ZionsWrath]

In the case of this thread, what is a street pad/track pad you can run without ruining the rotors. Meaning, without changing rotors what pad can I run on the street and when I get to the track swap to a different pad, and before going home from track put the street pad in. All that on same rotor. Basically 1 set of rotors, different set of street and track pads. This on AP racing sprint kit.

Thanks

[JRitt]

Guys...sorry I didn't have time to write a full response earlier. Here's the scoop:
The issue is the J Hook discs, and what you’re seeing is normal. If you look at that pic above, every concentric ring being worn on the disc is at the end of a J Hook. The spent pad debris collects in the J Hook, and then exits the J Hook at its termination and causes the grooves. Other than a cosmetic issue, there shouldn’t be any performance issues. This happens more when the brakes are cold, since they’re working in an abrasive mode…they’re scraping the discs rather than sticking to them. When you heat pads up on the track, they’re scraping AND sticking to the discs (and you get a pad transfer layer). You will find that some pads do this more than others because some pads have more material break loose from the pads, or the material that breaks away from the pad is more abrasive than materials from other pads. To anyone who does not know what is happening, I can definitely see how this would be a concern, and I probably need to get something up on our website about it. Again, this is normal and nothing to be alarmed about though.

If you don’t like the grooves or are worried about them, we sell a plain-face version of the exact same disc, and they are $155 per disc.

Right hand side= part# 19 01 720
Left hand side= part# 19 01 721

Finally, J Hook slots can cause a little more whirring and scraping noises, similar to drilled discs because there are more leading edges for the pad to catch on.

[JRitt]

Forgot to say...at $155 each, the plain face discs are $10 cheaper per disc than the J Hooks.

[CSG Mike]

Originally Posted by JRitt

Forgot to say...at $155 each, the plain face discs are $10 cheaper per disc than the J Hooks.

I want my bling

[Dave-ROR]

Originally Posted by JRitt

Guys...sorry I didn't have time to write a full response earlier. Here's the scoop:
The issue is the J Hook discs, and what you’re seeing is normal. If you look at that pic above, every concentric ring being worn on the disc is at the end of a J Hook. The spent pad debris collects in the J Hook, and then exits the J Hook at its termination and causes the grooves. Other than a cosmetic issue, there shouldn’t be any performance issues. This happens more when the brakes are cold, since they’re working in an abrasive mode…they’re scraping the discs rather than sticking to them. When you heat pads up on the track, they’re scraping AND sticking to the discs (and you get a pad transfer layer). You will find that some pads do this more than others because some pads have more material break loose from the pads, or the material that breaks away from the pad is more abrasive than materials from other pads. To anyone who does not know what is happening, I can definitely see how this would be a concern, and I probably need to get something up on our website about it. Again, this is normal and nothing to be alarmed about though.

If you don’t like the grooves or are worried about them, we sell a plain-face version of the exact same disc, and they are $155 per disc.

Right hand side= part# 19 01 720
Left hand side= part# 19 01 721

Finally, J Hook slots can cause a little more whirring and scraping noises, similar to drilled discs because there are more leading edges for the pad to catch on.

I swear I asked if you had those before!!

Damn.. I might buy a set.. I still have spare rotors (burnished too) sitting around.. hmph.

[Dave-ROR]

So anyone want to buy some brand new burnished J Hook rotors?

I might need to test me some plain face discs

[Hanakuso]

Nice. I prefer plain rotors. They probably make less noise as well.

[acro]

Can the sprint kit be bought with the plain rotor instead of the j-hook rotor

[dradernh]

Originally Posted by Dave-ROR

So anyone want to buy some brand new burnished J Hook rotors?

PM sent.