[ruczko]

I've got a set of EDC reds on order and wondering if replacing them without rotors is ok? If I do this and the rotors are 50% let's say, does that mean I have to replace the pads again with new rotors?

I'm not entirely sure how much life I have on the rotors so I'm not sure which direction to go.

[SwankPeRFection]

Is there a sizable lip on the outside edge of the rotor? Sometimes you can run a couple of sets of pads on a set of rotors, but it depends on how worn down they are. Take a clear close pic and post it. Maybe do different angles and we should be able to tell you if the pics show enough detail.

[mike@x-ph.com]

you can replace the pads without the rotors, i have done it on both my G82s

[ruczko]

Originally Posted by SwankPeRFection

Is there a sizable lip on the outside edge of the rotor? Sometimes you can run a couple of sets of pads on a set of rotors, but it depends on how worn down they are. Take a clear close pic and post it. Maybe do different angles and we should be able to tell you if the pics show enough detail.

Here are some pics. I do feel a lip for sure, not sure what is sizeable but it’s certainly there.

[codean]

General rule of thumb is, you can put a new set of pads an a used set of rotors that are still in good condition (clean and non warped surface), but you should NOT put a used set of pads on a new set of rotors.

Your rotors still look to be in decent condition. A slight chamfer with a metal file on the edges of the new brake pads would be suggested so they clear the lip of the old rotors.

[SwankPeRFection]

Rotors look fine. Run another set of pads on them, you’ll be fine.

[SwankPeRFection]

Originally Posted by codean

A slight chamfer with a metal file on the edges of the new brake pads would be suggested so they clear the lip of the old rotors.

DO NOT DO THIS. The rotor lip developed because the pads don’t sweep that area. The new pads won’t touch or ride on that lip. Also, the new pads will clear just fine to engage down when the caliper is reinstalled because the pistons should be all the way retracted back into the caliper, which puts the clearance back to stock new rotor thickness, which is what that lip is at. Leave the new pads alone. Installed them and move on. On next change, that inner and outer lip on the rotor will probably be enough to warrant a rotor change… this depends a lot of pad composition and driving habits of the owner.

[codean]

You make a lot of of assumptions to use an all caps warning like that. Rust ridges exist. Rotor edges don't wear at a 90 degree angle. Not all brake pads are the same exact size.

Putting a slight chamfer on a pad doesn't hurt anything. Best thing to do is place the pad on the rotor and see how it rests and decide from there.

[SwankPeRFection]

Originally Posted by codean

You make a lot of of assumptions to use an all caps warning like that. Rust ridges exist. Rotor edges don't wear at a 90 degree angle. Not all brake pads are the same exact size.

Putting a slight chamfer on a pad doesn't hurt anything. Best thing to do is place the pad on the rotor and see how it rests and decide from there.

Very and I mean very (as in the new pad manufacturer didn’t design the pad to OEM standards, in which case you don’t want them anyway) rarely do pads not line up with the came clearances. I have gone from OEM to Pagid to other OEM to iSweep and the pads were all the same size with no messing with the new pad being necessary. No pad ever rides the very edge of a rotor. Spacing of ~2 mm is required as a safety for the pad not to wear the pad’s edge and run the risk of shattering during hard braking due to non-full pad material contact. The same goes for the inside edge of the rotor. The OEM pad measurements are there for a reason and have to be met. Also, resurfacing of a rotor is done in cases where the previous pad left a non-flat surface on the contact patch of the rotor as it wore down… not even in that case is resurfacing done to remove the outer lip. It will be removed as part of the process, but that’s not the sole or main purpose of the resurfacing process. Just some additional FYI.

Ultimately, people can do whatever they want, but you made it seem like it should be done no matter what and that’s just messing with perfectly new and good pads for no reason. Sorry, but I’ve seen too many mechanics do some stupid ass shit that wasn’t necessary just because they were mistaught.

[codean]

BMW literally has a labor operation code for chamfering brake pads. They also state to perform it to help with noise issues in an SIB.

But maybe you know more than they do, I don't know what your background is.


I never said " YOU HAVE TO CHAMFER THE BRAKE PADS"... I did suggest it, because doing so doesn't cause any negative effects and I can't see how there EBC red pad is going to sit on their used OEM rotor.

[SwankPeRFection]

Originally Posted by codean

BMW literally has a labor operation code for chamfering brake pads. They also state to perform it to help with noise issues in an SIB.

Chamfering on the directional edges (like most come from the factory when new) is done for noise suppression. As you wear down the pad, this chamfered edge area gets smaller and smaller and that’s when some noise can start happening over the life of the pad. BMW doesn’t want to replace your pad at 50% usage left, so when you complain about it, they’ll file your pads down some to shut you up and not give you new pads. Some really cheap pads also don’t come with this angled edge, so if you manually put one on, it can keep the pads quiet to some degree. Most legit pads for sport sedans or coupes have it stock as part of the design.

[codean]

Not talking about directional edges of the pad being chamfered. Here is bmw documentation which shows this. Second image even shows chamfering a new brake pad when using a used rotor.

Link to pdf for of bmw brake repair poster: https://bmwtechinfo.bmwgroup.com/sib...l%20Poster.pdf

[SwankPeRFection]

2017 and it says “All except M models”.


OK…

[SwankPeRFection]

OP, look. Take your new pads and place them on the rotor. If the pad material sits flat on the rotor and in between your two rotor ridges that are there due to normal wear from the previous pads, install them as you would normally and move on. You can take this extra step and check that before even taking anything off if you’re reading all the stuff above and are second guessing yourself in any way. Good luck with the swap, I’m sure you’ll be fine.

[codean]

Originally Posted by SwankPeRFection

2017 and it says “All except M models”.


OK…

Yep, and you already know why M models aren't included for brake noise remedies though an SIB... hence why you have iSweeps.

[SwankPeRFection]

Originally Posted by codean

Yep, and you already know why M models aren't included for brake noise remedies though an SIB... hence why you have iSweeps.

I will have iSweeps because I ran iSweeps on the S4 for like ever due to it being a better pad than what was available for both my back brakes and the front Macan calipers I ran on it. That is just as soon as I can get my hands on a set of 2500’s from what seems like just one damn US vendor, which I’m not a big fan of lack of choice. I don’t care about brake dust or noise. I care about how my brakes feel for my driving habits. I’ll generally will go function over form for mods I choose all the cars I’ve ever had.

[ruczko]

Thanks for the help folks, didn’t think it would get this heated (pun intended). Pads are in their way and I just need to find some brake sensors. Suggestions on where to get those?

[SwankPeRFection]

If they haven’t popped, then you don’t need to replace them.

[BlueBeamer]

On our race cars we would normally go thru three sets of pads before needing to replace the brembo rotors
Unless you have 80k miles on your pads and rotors it’s not needed

[Zippyy]

Originally Posted by ruczko

Thanks for the help folks, didn’t think it would get this heated (pun intended). Pads are in their way and I just need to find some brake sensors. Suggestions on where to get those?

Got mine on rock auto. Super cheap.