mazda3rally

Can anyone tell me if there are 2-piece rotors for a 2007 Mazda3 Sport GT, currently I am feeling pulsations in the peddle. The car has 32,000kms on it and I know that these cars tend to have their brakes wear out sooner than other cars and I know its because of the great grip that these brakes have but I need rotors that won't warp. Historically I've always had a problem with warping rotors and have tried most makes of rotors including crossdrilled Brembo's on my prior car a Subaru Impreza. Now I know the sliders are free to move on the calipers so that is not why they warp it just seems to be due to me being rough on my brakes cause I've never had a rotor last me more than 25K before warping and some of the cheap ones only last 1000kms before warping so I want to go with some really high end rotors so that the rotor will wear out before it warps. This is why I'm looking at some 2 piece rotors, can anyone give me any advice?

Thanks
Gerald

ceejay

Hmmm...I changed my first set of rotors at 72,000mi in preparation for a track day...The rotors I put on are now slightly warped after the track day, but I had no issues with the original oems (my driving is 90% highway...and I don't brake for off ramps except in the winter).

I considered drilled rotors for my track day, but was advised it would be a waste of money from a supplier, unless I intended to spend more time on track..(which I don't )

Chibana

I've found that the brakes on my 2005 Mazda3s 4-door are by far the best of any car I've ever owned, and I don't mean that just from a performance perspective. They have always been low on brake dust compared to other OEM brake systems, they have not had the "warping" (that's a misnomer in the vast majority of cases) issues that were not easily resolved myself, and I didn't have to have ANY brake work done until the car was just over 3 years old and had about 110,000 miles on it. At that time, just a few months ago, I had to have the rear disks and pads replaced. The fronts haven't needed it yet, but I have a feeling that's coming soon.

The "warping" that people notice is, in the vast majority of cases, not any warping of the rotor at all, but rather uneven break pad material deposition onto the rotor (from panic stops, etc.). Whenever I started to feel the hint of pedal pulsations in my Mazda3, I was able to clear it up by performing the new brake procedure of several, firm stops from about 65 mph to 10 mph or so. A few good brake applications like helps to clear up the uneven brake pad material deposits on the rotor, and will generally eliminate the pulsations. At least, it always has for me with my Mazda3.

In addition, in ever other car I've owned I tried various after-market "improvements" to the braking system, and they were always a mistake, and made one or more aspects of braking worse. I think you really have to know braking systems well, and properly understand your braking goals, to be able to make intelligent choices about after-market upgrades to your brakes. Unless you're doing significant tracking with your Mazda3, and you really know what you're doing, you will almost certainly cause more harm than good by replacing rotors or pads with after-market components.

mazda3rally

Seems like most of you get a lot of kms out of your rotors and its good to hear, now in regards to my situation, Chibana, at first I was skeptical about your solution but figured I really didn't have anything to loose. So I tried braking in the breaks and after about 10 times I felt a very minor improvement so I've tried it about 50 times now and it has improved but not gone away. My question now is I've tried driving with 2 feet with the brakes on for a length of 500 meters or so to clean the pads. Now in order to determine if the warped rotors were the front or rears I pulled the handbrake rather tight and drove 500 meters to see if I would notice pulsation, I didn't which tells me that its the front rotors. Now my question is why would it be that consistent stops from 100km/h - 20 km/h would be any different in terms of evening out the pads?

Chibana

It's my understanding that this bedding process "cleans up" the rotors. I think I read that it *evenly* (and that's the key) distributes a thin layer of brake pad material on the disk, and is supposed to be done for new brakes (rotors and/or pads), but I also read that it helps when you notice pulsation. I suspect that if the pulsation is really bad, it's not going to fix the problem, but maybe smooth the rotor surface out a bit, which sounds like what you found. My guess is the reason it's worked for me all this time is that the pulsations were never all that bad--just a hint of it starting.

onebad3

If you or the dealer installs your wheels with an impact gun that will warp the rotors every time. I always ask them to use a torque wrench and have not had warping issues since.

mazda3rally

Thanks for the input, and onebad3 usually I'd agree with you but I never let the dealer rotate the tires and make sure of that cause of the wheel locks on my car. Usually anything involving taking off the wheels I do myself and always have used a good torque wrench to tighten them. It does seem like its odd to have the rotors warp but really most rentals that I've ever driven in a spirited way has resulted in pulsations in the brake pedal, now manual transmission cars last a lot longer due to engine braking but on the rentals here in North America with automatics the brakes always seem to get damaged rather quickly.