Machining rotors

[TheDuke]

Can you machine slotted and drilled rotors? I got brembos both sides, they seem to be wrapped. Not even after a year of driving. It looks like I only have to do the front.

[Jay 535i]

You can, but everyone here will tell you that if you machine a rotor that's noticeably warped you'll seriously reduce your brakes' resistance to fade and the rotors' ability to withstand the stresses of normal use. In other words, you'll be shopping for new rotors soon anyway.

I would think that Brembos ought to last more than a year. Maybe someone can shed light on why you've gone through them so fast.

[TheDuke]

I am using Rybestoes QS for pads, the problem started about two months ago. Right now it's shaking really bad. I still should have warranty on them somewhere. Exactly thinking Brembo should do quality parts, they make brakes for Ferrari don't they. Maybe I was pushing them too hard.

[Kalevera]

It's stupid to machine any BMW rotor. The company explicitly condemns it for M car hardware, and I've replaced enough machined rotors on stingy peoples' cars to know that it's not a fluke or a freak accident.

Get new rotors, they're cheap.


best, whit

[uscharalph]

It's stupid to machine any BMW rotor. The company explicitly condemns it for M car hardware, and I've replaced enough machined rotors on stingy peoples' cars to know that it's not a fluke or a freak accident.

Get new rotors, they're cheap.


best, whit
I agree with Whit.

[DaCan23]

If by "not even after a year" you mean the rotors were brand new and after less than a year this issue arised, check with where you bought them about warranty/defective. There have been cases of bad lots of rotors from different manufacturers.

Other than that, never turn rotors, thats the consensus opinion.

Also check mis installation that could of caused the warping.

[632 Regal]

another back to basics scenerio im tring to work on.

pull all the roters, sand, wire brush clean till theres nothing there, I mean a clean surface. then clean the back of the rotor mating surface before you go and cut a decent rotor.

then reassemble and try to break in propely...blue balls is normal.

edit: i mean blue rotors after break in is normal and a good sign.

[TheDuke]

I tkink I will go with zimmerman and try to return the old brembos.

[shogun]

Hmmh,
if you ask such a question and tell us that they are in not even a year:
"a year" does not mean anything.
How many miles or km did you do in that time, that is the point.
Some people drive 50 K miles a year, other less than 5.

[Beemr750]

I'm having the same problem with my frt brakes.Replaced them 3400 miles ago with QS pads and Raybestos rotors.So far it only is noticable above 60 and when hot.I'l have them checked and maybe turned otherwise I will get Ate again.

[TheDuke]

My bad about not specifying the mileage, too lazy to go and check it. I keep a little black book in my car with all maintenance records. Well I'm sure it is less than 12K miles. I thought the issue was thrust arms and bushings so I replaced them, with no effect. I still cannot believe brembos going bad after such a short period of time. I put $20 rotors on my brothers Toyota and they seem to hold up much better than brembos.

[Bellicose Right Winger]

I suspect that one reason new rotors are so much cheaper then they use to be, is that they aren't heat aged to reduce internal stresses, hence they are more prone to warping after owner heats them up with sporty driving. I had to turn a new set of Balos w/ only 8K miles after I got a brake induced shimmy. They've been fine for the last 40K. In 30+ years of DIYing, I've never regretted turning rotors, but it's only cost effective if you are providing all the labor.

Paul Shovestul




My bad about not specifying the mileage, too lazy to go and check it. I keep a little black book in my car with all maintenance records. Well I'm sure it is less than 12K miles. I thought the issue was thrust arms and bushings so I replaced them, with no effect. I still cannot believe brembos going bad after such a short period of time. I put $20 rotors on my brothers Toyota and they seem to hold up much better than brembos.