Front/Rear Disc Replacement

[CF105]

Hello all,

This is my first post on this forum, so I'm a real newbie.

I have a quick question regarding front and rear disc replacement. I've been inspecting my discs closely over the last couple of months and have noticed some moderate grooving. I thought I might bring 'em over to the machine shop and have them turned but figured it might be a good oportunity for me to upgrade to slotted discs.

Is it neccesary to change the pads when replacing the rotors, or will the original pads simply rebed themselves harmlessly to the new discs?

Thanks,
Mike.

 

[CF105]

I realise this may seem like a question that has been asked on this forum at least once before, but I assure you, I've searched this forum in vein for any related threads that may answer this. The answers I've recieved thus far have been mixed. Just looking for someone to shed a little more light on the matter.

Thanks in advance.

 

[calimazda3]

If there'smoderate grooving, depending on the minimum thickness they may or may not be able to turn them, you'd have to check at the brake shop or anywhere they can turn them for you.

I just upgraded to StopTech's slotted front and rear brakes with there pads as well front and rear and after bleeding the lines with fresh Motul RBF600, and bedding them in, I am very pleased with them!!!!!!

 

[CF105]

I've only got about 20k on the vehicle, my average disc thickness is still pretty much at the 0.980" nominal thickness. I've taken off the discs and measured the groove depth on the marble table at my place of work with a dial indicator, when installing my winters. They aern't much greater than about .007" deep and roughly 0.050" wide. A groove like this is generally nothing to worry about (it has almost no bearing on the braking performance), its just that, aesthetically, it looks awful when my summer tire and rims are installed. I want them gone, and seeing as how I've got 0.040" of thickness to play with, I have more than enough material to turn them (As per Mazda Shop Manual: Minimum thickness after machining using a brake lathe on-vehicle
23.8 mm {0.94 in}).

...But...although its considerably cheaper to turn the rotors rather than replace them altogether (especially w/ slotted discs), I'm still tempted to use this opportunity as an excuse to slap on some slots.

I assume the pads that came with your StopTechs are ceramic. How's the wear rate? Average cost for kit (Rotors & Pads)?. Are they a perfect swap with the stocks?

 

[calimazda3]

I've got the StopTech Street Performance pads. So far so good. They've actually gotten a lil bit better since I just put them on recently. Wear rate, can't tell much since there still fairly new. Here's the page there on StopTech's site:

http://www.stoptech.com/Products/high_performance_pads.shtml

The first pad description, chart:

Got the deal from Tri-Point Engineering for the pads for complete set, front and rear pads, $107. Front and rear slotted rotors by StopTech as well and got Motul RBF600 as well. It wasn't too bad, but me stopping quickly with these were worth the $$$.

You get hit up Jeff, I know he's a sponsor on here too, here's the info: https://s69063.gridserver.com/contact_us.php?osCsid=ade2edbb699db6c9ffc3ccbf63d98db0

Tell him your on the forums and he'll take care of the pricing etc. (forum pricing etc)

I don't recall the exact cost of everything, but I did remember the special on the pad set. And yes, there a simple bolt on, OEM direct replacement.

 

[CF105]

Thanks a bunch, calimazda3.

Performance numbers look pretty solid. Think I'm gonna ponder it for a while but I just might consider giving that Jeff a call.

 

[meicalnissyen]

I've only got about 20k on the vehicle, my average disc thickness is still pretty much at the 0.980" nominal thickness. I've taken off the discs and measured the groove depth on the marble table at my place of work with a dial indicator, when installing my winters. They aern't much greater than about .007" deep and roughly 0.050" wide. A groove like this is generally nothing to worry about (it has almost no bearing on the braking performance), its just that, aesthetically, it looks awful when my summer tire and rims are installed. I want them gone, and seeing as how I've got 0.040" of thickness to play with, I have more than enough material to turn them (As per Mazda Shop Manual: Minimum thickness after machining using a brake lathe on-vehicle
23.8 mm {0.94 in}).

...But...although its considerably cheaper to turn the rotors rather than replace them altogether (especially w/ slotted discs), I'm still tempted to use this opportunity as an excuse to slap on some slots.

I assume the pads that came with your StopTechs are ceramic. How's the wear rate? Average cost for kit (Rotors & Pads)?. Are they a perfect swap with the stocks?

THANK YOU
for answering my question, I have the car apart right now, had bad ridges on the L front, took em down with a die grinder while the car was idling in first. needed to know the disc wear limit

found it from a guy with 6 posts

right on

Oh, your surface plate is granite, marble is a very soft mineral ;-) (canada)

mike, ex machinist

 

[DynoBunny]

I have over 60k miles on my car. The back rotors and pads are still good. I replaced the front pads with hawk hps at about 40k and had the rotors turned. Everything is still ok for me. I really can't believe how long the back brakes have lasted, I think they will go another 15k miles, it's crazy.

 

[DynoBunny]

BTW The machine shop told me when they resurfaced the front that they were below spec and would probablly warp, however 20k plus miles later and they have been fine.

 

[calimazda3]

^^Lucky. Just keep an eye on them.

 

[binhsterbinh]

I went with Tri-point engineering's Stoptech High Performance pad deal for $107 as well. I also installed Centric Premium Rotor all around as well with the black e-coating from protege garage. I'm very satisfied. Total out the door cost with my own labor was about $270 for all four corners. After the pads bedded in, braking performance was significantly improved compared to the ceramic ones that came with my used car. The Stoptech pads do dust though just so you know but for the performance and cost, they're more than worth it.
After 2 months of not washing, here is a picture of Stoptech dust/grime after hosing rear wheel off before I scrubbed them down: