ND2 Uneven rear brake disc wear

Technical Area Wheels, Tyres & Brakes
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  1. My model of MX-5 is: __ late 2019 2.0 ND2
  2. I’m based near: __ Inverurie
  3. I’m looking for technical help or recommendations on: __ I changed front and rear discs and pads last week and noticed the same pattern appearing on my rear discs. (Brembo pads and discs) The old disc had a ~1cm lip where the pad had not made full contact with the rotor. Now with 4 new discs installed, the rears look to be suffering the same. Any ideas? photos of old and new.
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Is it happening like that both sides as NS/OS on the rears?
Did you use brake cleaner on the new discs and pads before installing? It does look like contamination on the disc from that picture.
I’ve had brake discs look that bad (the ones removed) not on an MX-5 though. I considered it lack of brake maintenance before my ownership, I had to replace them with new. I used Brembo discs and pads on both my daily and MX-5, all been good.

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Yeah, both sides, and loads of brake cleaner and rags to remove oily fingerprints from the new discs prior to, and after installation.

The car only had 11000 miles on the clock when I got it two years ago. So very low mileage, and having found a Motzart CD in the CD player would suggest very gentle driving style from the previous owner, hence not much wear and lots of corrosion on the rears :laughing:

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I thought loads of boy racers listen to Mozart :thinking:

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Rock me Amadeus :rofl:

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Yeah sounds like it’s not been used much and the rear brakes never really get a good cleaning from the pads.

My daily drivers rears, had 35k miles on in 10 years when I sold it. One disc had an odd wear pattern, unexplained, so although the pads and discs had plenty on life left in the age and not frequently used had took its toll.

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Sounds a bit extreme but even on my daily driver now (no MX-5 ATM) I run round the block to dry the brakes after washing it and never park it on my driveway or in the garage (all flat) with the handbrake on. I found the MX-5 worse for the brakes sticking on when it’s been wet, you could see the rusty marks left when wet too

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I would check that the pads are moving freely in their holders. I had the N/S rear binding slightly and had to file the tabs on the pads as they were too tight in the guides.

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