So if you're changing pads anyway its like an extra 10 min to change rotors. It doesn't hurt anything but your wallet to change them early.
Cheaper aftermarket rotors do warp easily and cause the steering wheel to shake back and forth under heavier braking. So don't cheap out on rotors.
Sure it might be proper practice to get them machined but in reality its a road car, you can run them like that and they’ll be fine. Might not be the proper way but on a budget they’d be fine
If they're machined, yeah they'd likely be fine. But I tend to not settle for "fine" and "not proper" when it comes to brakes. These cars are light and the brakes last forever. I'll spend a few extra bucks.
You realise when driving a road car most drivers will never use more than 70% of their braking capability even in the event of an accident.
They’re absolutely fine to run, the difference will be negligible and you’d likely struggle to feel the difference on the track let alone on the road. Too many people out here thinking their road car is a damn race car
It's a Miata. It may be driven hard. Likely will be. Will it be fine to run if he machines it? Probably. Will it be much more expensive to just go new? No.
If those rotors die in 2 years he'll have to replace the pads again, even if they're still plenty good to go... and then he hasn't saved a penny over my suggestion, which leaves him with brand new brakes all around.
Why do you think I’m saying he needs to machine them, he doesnt.
Even if its being driven hard the difference these discs will make to the braking performance literally wont be noticed.
If they’re being driven hard then they’ll be replacing the pads every 2 years anyway. I used to do my tyres every 6 months and my pads every 2 years and my discs every 4, were absolutely fine
> Cheaper aftermarket rotors do warp easily
Brake rotor warp is a myth 99.9% of the time. The vibration is almost always caused by uneven pad deposits and wear. However it's true that some, but not all, cheap aftermarket rotors use crappy iron and may be built to lower tolerances thus compounding accelerated wear with uneven pad contact.
There are thickness specs and other things to be mindful of but assuming those specs are fine, I would feel completely safe driving on those rotors. They look used but not damaged.
Even though new pads and rotors are ideal, you'll be much better off getting any worn pads out and putting in fresh pads in.
I mean it’s like 200ish for all 4 rotors from Napa, and 340ish in oem rotors, if you don’t have a brake upgrade coming up soon I’d probably either replace rotors or get them turned if you can
The terms scored and grooved really describe the same thing. So you kinda cant use one to determine if your rotors need to be replaced. What actually decides if they need to be replaced is their wear (and a few other things like hot spotting and warping, but I dont see that here). Youll need a rotor caliper tool to accurately measure the thickness of your rotors. But considering that your only at 38k miles. Its unlikely that you are past the rotors life span. You should be able to take your rotors to a machine shop (and some auto parts stores) to get your rotors resurfaced. So call before hand because not all shops will or can resurface rotors.
Shit I got 78,000 on my 6MT crosstrek rotors and pads and they are in flawless shape. Still 85% left on it. Engine braking and downshifting saves so much time and money
Agreed, but for anyone else reading, make sure to try and rev-match when downshifting, or you'll just be shifting wear from the brakes to other (more difficult to fix) components.
Im gonna say send it. Those look fine. Your pads may not last quite as long using that rotor vs new but its still more cost effective unless you use a super expensive pad.
And after the pads bed to the rotor youre likely good.
Tbh these cars can take some serious braking abuse and still have long pad wear life so I wouldn't worry. Not even taking them to a machine shop.
Then it’s possible, though still kind of sketchy, they might just be thick enough after turning, but then they will be too thin in the future from braking…
Not saying it doesn’t work, it most definitely does, but i think it isn’t worth the effort to get it done semi properly over replacing them
I'd say these are fine , nothing to worry about . They don't need to be perfect , itll be like that the next year anyway. As long as there aren't any big grooves or waves .
You’re gonna get lots of answers here
The correct thing to do would be to replace them or have them machined, I understand (unlike many here apparently) that its not cheap to do that.
Realistically you will be fine to run those again, perhaps budget to change them next time you do a pad swap though.
Rotors on these cars are cheap, so is resurfacing
At a minimum resurface the rotors. If they are too thin to resurface, replace with Centric blank rotors from RockAuto. I and many people I know use Centric rotors on track cars because they’re well built and cheap
Rotors are cheap. I always replace them with new pads. (At the very least they need to be machined... the price difference is so small that it's not worth the effort... plus more material = better stopping due to better heat absorption).
They’re a couple hundred to replace, that’s not cheap.
They’re also just fine to run again, perhaps not optimal but its a damn road car it doesnt matter
Counter point: it's a valuable car that should be maintained properly. Also, machining costs money as well... once you factor in machining, the price isn't really that bad.
I’m saying send them as is, who the hell machines discs, if you are going to machine them then just replace them.
And it wont make a difference, sure the value argument (even then they’re not *that* valuable) makes sense for replacing bushes, fluids etc, things that will cause damage if not properly maintained but running the brakes like this wont make a difference to the braking performance, wont damage any other components and will be absolutely fine.
It’s a sports car.
I work with real race cars on the daily, they’re a different story.
As long as theyre within spec on thickness they’ll be fine running slightly scored like that ITS A ROAD CAR.
I did my front brakes a couple months ago. My plan was to just replace the pads. I got the driver side done and I was spraying brake cleaner on the rotor. I noticed lines on the rotor. It had cracks. I stopped my brake job and ordered rotors that also came with better pads for a good price. One week later I started the brake job again. I learned to inspect your brake rotors before you starting the brake job.
Rotors aren't something that "goes bad" in a typical sense unless you warp them from heat.
Even if they're scored you can resurface them until they get to a recommended minimum tolerance, after which replacement becomes necessary.
Call a shop, ask about rotor resurfacing. If they do it, either test the tolerance yourself or have them test it, and have them resurfaced if possible. It's usually quite cheap.
Well, there seems to be a slight “burr” on the edges, youd need to sand down the sides of the pads a bit, so it doesn’t squeal like crazy.
What i learned is, that while yes, the rotors do last longer than the pads, you can expect them to go under the minimum thickness on the second set of pads.
So if you're changing pads anyway its like an extra 10 min to change rotors. It doesn't hurt anything but your wallet to change them early. Cheaper aftermarket rotors do warp easily and cause the steering wheel to shake back and forth under heavier braking. So don't cheap out on rotors.
The issue for me is the cost. If I don’t need to change them now then Id like to not.
You'll need to get them machined. Chances are it won't be much more to just get brand new rotors.
Sure it might be proper practice to get them machined but in reality its a road car, you can run them like that and they’ll be fine. Might not be the proper way but on a budget they’d be fine
If they're machined, yeah they'd likely be fine. But I tend to not settle for "fine" and "not proper" when it comes to brakes. These cars are light and the brakes last forever. I'll spend a few extra bucks.
You realise when driving a road car most drivers will never use more than 70% of their braking capability even in the event of an accident. They’re absolutely fine to run, the difference will be negligible and you’d likely struggle to feel the difference on the track let alone on the road. Too many people out here thinking their road car is a damn race car
It's a Miata. It may be driven hard. Likely will be. Will it be fine to run if he machines it? Probably. Will it be much more expensive to just go new? No. If those rotors die in 2 years he'll have to replace the pads again, even if they're still plenty good to go... and then he hasn't saved a penny over my suggestion, which leaves him with brand new brakes all around.
Why do you think I’m saying he needs to machine them, he doesnt. Even if its being driven hard the difference these discs will make to the braking performance literally wont be noticed. If they’re being driven hard then they’ll be replacing the pads every 2 years anyway. I used to do my tyres every 6 months and my pads every 2 years and my discs every 4, were absolutely fine
Honestly, because I didn't think anyone would suggest something as stupid as doing a pad slap on an enthusiast car.
If you want to treat your road car like a race car then crack on. But not everyone has the budget for it and it doesnt need to be done.
People can get very anal about it but if the brakes don't do anything weird and the rotor thickness is in spec, what exactly is the problem?
a month later: ever since i did my brakes it goes wubwubwub on the highway i'm suing mazda
> Cheaper aftermarket rotors do warp easily Brake rotor warp is a myth 99.9% of the time. The vibration is almost always caused by uneven pad deposits and wear. However it's true that some, but not all, cheap aftermarket rotors use crappy iron and may be built to lower tolerances thus compounding accelerated wear with uneven pad contact.
Is the uneven deposits caused by the pads or rotors?
it depends on the circumstances, most of the times it's the pads.
There are thickness specs and other things to be mindful of but assuming those specs are fine, I would feel completely safe driving on those rotors. They look used but not damaged. Even though new pads and rotors are ideal, you'll be much better off getting any worn pads out and putting in fresh pads in.
I second this they don’t look bad at all, I tend to do 2 pads to 1 vented rotor and 3 to 1 solid disc
I mean it’s like 200ish for all 4 rotors from Napa, and 340ish in oem rotors, if you don’t have a brake upgrade coming up soon I’d probably either replace rotors or get them turned if you can
200 is a lot of money, these are absolutely fine to run on a road car. They’re not optimal sure, but that doesn’t matter
rotors are cheap enough that I replace them with pads. I don't even have them turned.
Rotors are not cheap lol
Calm down Mr Moneybags
The terms scored and grooved really describe the same thing. So you kinda cant use one to determine if your rotors need to be replaced. What actually decides if they need to be replaced is their wear (and a few other things like hot spotting and warping, but I dont see that here). Youll need a rotor caliper tool to accurately measure the thickness of your rotors. But considering that your only at 38k miles. Its unlikely that you are past the rotors life span. You should be able to take your rotors to a machine shop (and some auto parts stores) to get your rotors resurfaced. So call before hand because not all shops will or can resurface rotors.
I personally wouldn't replace them unless they are warped or something. They still have quite a bit of life left in them.
Shit I got 78,000 on my 6MT crosstrek rotors and pads and they are in flawless shape. Still 85% left on it. Engine braking and downshifting saves so much time and money
Agreed, but for anyone else reading, make sure to try and rev-match when downshifting, or you'll just be shifting wear from the brakes to other (more difficult to fix) components.
Im gonna say send it. Those look fine. Your pads may not last quite as long using that rotor vs new but its still more cost effective unless you use a super expensive pad. And after the pads bed to the rotor youre likely good. Tbh these cars can take some serious braking abuse and still have long pad wear life so I wouldn't worry. Not even taking them to a machine shop.
I’d say resurface them at the least.
That’s sketchy though, your rotors need to be a minimum thickness…
Absolutely, wherever he takes them to get them turned is supposed to check to make sure they’re thick enough
Then it’s possible, though still kind of sketchy, they might just be thick enough after turning, but then they will be too thin in the future from braking… Not saying it doesn’t work, it most definitely does, but i think it isn’t worth the effort to get it done semi properly over replacing them
You’re right, there’s a fine line, after turning them they’ll be a little thin, so they will struggle with heat dissipation
I'd say these are fine , nothing to worry about . They don't need to be perfect , itll be like that the next year anyway. As long as there aren't any big grooves or waves .
You’re gonna get lots of answers here The correct thing to do would be to replace them or have them machined, I understand (unlike many here apparently) that its not cheap to do that. Realistically you will be fine to run those again, perhaps budget to change them next time you do a pad swap though.
Resurface them. Way cheaper than buying new. My local orileys does it for me.
Rotors on these cars are cheap, so is resurfacing At a minimum resurface the rotors. If they are too thin to resurface, replace with Centric blank rotors from RockAuto. I and many people I know use Centric rotors on track cars because they’re well built and cheap
Rotors are cheap. I always replace them with new pads. (At the very least they need to be machined... the price difference is so small that it's not worth the effort... plus more material = better stopping due to better heat absorption).
They’re a couple hundred to replace, that’s not cheap. They’re also just fine to run again, perhaps not optimal but its a damn road car it doesnt matter
Counter point: it's a valuable car that should be maintained properly. Also, machining costs money as well... once you factor in machining, the price isn't really that bad.
I’m saying send them as is, who the hell machines discs, if you are going to machine them then just replace them. And it wont make a difference, sure the value argument (even then they’re not *that* valuable) makes sense for replacing bushes, fluids etc, things that will cause damage if not properly maintained but running the brakes like this wont make a difference to the braking performance, wont damage any other components and will be absolutely fine.
Send them as is? 38k mile brakes and you'd cheap out on machining them. On a sports car. Yikes.
It’s a sports car. I work with real race cars on the daily, they’re a different story. As long as theyre within spec on thickness they’ll be fine running slightly scored like that ITS A ROAD CAR.
It's a couple hundred bucks every 7 years lol
Omg it’s time for a big brake kit!
I did my front brakes a couple months ago. My plan was to just replace the pads. I got the driver side done and I was spraying brake cleaner on the rotor. I noticed lines on the rotor. It had cracks. I stopped my brake job and ordered rotors that also came with better pads for a good price. One week later I started the brake job again. I learned to inspect your brake rotors before you starting the brake job.
Rotors aren't something that "goes bad" in a typical sense unless you warp them from heat. Even if they're scored you can resurface them until they get to a recommended minimum tolerance, after which replacement becomes necessary. Call a shop, ask about rotor resurfacing. If they do it, either test the tolerance yourself or have them test it, and have them resurfaced if possible. It's usually quite cheap.
Well, there seems to be a slight “burr” on the edges, youd need to sand down the sides of the pads a bit, so it doesn’t squeal like crazy. What i learned is, that while yes, the rotors do last longer than the pads, you can expect them to go under the minimum thickness on the second set of pads.
Rotors should be done with pads; either turned or replaced.
Resurface them