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Discussion Starter #1
How close to minimum thickness should the rotors be replaced? Cayman R so assuming the same as the Cayman S:


Rotor Thickness Original Minimum
Cayman S Front - 318mm Dia. 28 mm 26 mm
Cayman S Rear - 299mm Dia. 24 mm 22 mm


Just replaced the pads this morning and measuring the rotors.


I am good on the back because they are at 23.5 or so all over.


The front is where I have the question. They are above the minimum at 26.5 or higher. So the question is do I need to replace now or can I just keep monitoring?


Thanks


Andrew
 

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Depends ... If you want to Do Stuff to the car or are obsessing about that half mm, replace them.

Depends ... If you're doing street driving, replace them with the next set 'o pads. If you're headed to the track and not for your first or second DE [I.e. are really *using* the brakes at the track], replace the rotors first. Rotor mass is key to avoiding brake fade.

Depends ... How long have you taken to wear the rotors to their current worn state? If several years, you're just not using the rotors very fast; do them with the next set of pads.

Depends ...

mmmv,

-PM .
 
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Discussion Starter #3
Depends ... If you want to Do Stuff to the car or are obsessing about that half mm, replace them.

Depends ... If you're doing street driving, replace them with the next set 'o pads. If you're headed to the track and not for your first or second DE [I.e. are really *using* the brakes at the track], replace the rotors first. Rotor mass is key to avoiding brake fade.

Depends ... How long have you taken to wear the rotors to their current worn state? If several years, you're just not using the rotors very fast; do them with the next set of pads.

Depends ...

mmmv,

-PM .
Not obsessing just didn't have any data points on usage because I just bought my measuring tool today.
Just getting into DEs.
Bought car used so I cannot speak to usage.
 

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If you plan to track the car(DE, lapping days), I would change the front's now. Nothing worse than the brake wear light coming on on the track.:(
 

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Not obsessing just didn't have any data points on usage because I just bought my measuring tool today.
Just getting into DEs.
Bought car used so I cannot speak to usage.
If you're just getting into DE I'd recommend changing the brakes yourself just to familiarize yourself with all the parts. It will also set a good baseline for you to start monitoring wear. You'll want to at least get proficient at bleeding your brakes as this will become a common chore that can add up if you decide to do DEs a lot.

Basically I'm saying you want your brakes to be in top notch shape if you are starting to pick things up at a DE.
 

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If you plan to track the car(DE, lapping days), I would change the front's now. Nothing worse than the brake wear light coming on on the track.:(
The wear indicator light is for pads, not rotors. He just replaced his pads.
 

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I could be wrong, but I would assume that you'll see cracks long before you'll notice missing surface material. OE drilled discs will start to develop tiny cracks above and below the holes. The cracks will grow. At this point they should be replaced but don't need to be til they worsen. No matter OE or race, you never ever ever ever ever want your cracks stretching the distance of the annulus of the disc. If you have a crack headed to the outter extremities, STOP!
 

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How close to minimum thickness should the rotors be replaced? Cayman R so assuming the same as the Cayman S:


Rotor Thickness Original Minimum
Cayman S Front - 318mm Dia. 28 mm 26 mm
Cayman S Rear - 299mm Dia. 24 mm 22 mm


Just replaced the pads this morning and measuring the rotors.


I am good on the back because they are at 23.5 or so all over.


The front is where I have the question. They are above the minimum at 26.5 or higher. So the question is do I need to replace now or can I just keep monitoring?


Thanks


Andrew
Does anyone know what the min. thickness is for front/rear rotors on a 08 Cayman 2.7?
 

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The wear indicator light is for pads, not rotors. He just replaced his pads.
Ya, I could have worded that better.

New pads with new rotors have the best grab, and after that you have to know the surface condition of the rotor to see if you can lathe them, and still be above the minimums. Easier just to change them now.

The wear light comment had nothing to do with the OP, just my experience.
 

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I could be wrong, but I would assume that you'll see cracks long before you'll notice missing surface material. OE drilled discs will start to develop tiny cracks above and below the holes. The cracks will grow. At this point they should be replaced but don't need to be til they worsen. No matter OE or race, you never ever ever ever ever want your cracks stretching the distance of the annulus of the disc. If you have a crack headed to the outter extremities, STOP!
+1 on the above. You will see cracks in the disc, more visible on drilled discs like the OEM discs, then its time to change them.
 

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I'd replace rotors when the cracks reach the outer edge. Been there, done that many times. You'll actually get great amount of usage out of them even when the cracks connect from hole to hole. I know from experience (more than just once). Once the cracks go to the outer rim (in addition to connecting the holes), it's time to replace.
 
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