I agree with the above, and, specifically, on Hawk's site, this part on bedding them in:

What is the proper procedure for braking in new brake pads?

Brake pad break-in procedure.

After reaching medium speed engage brake pedal to slow car without coming to a complete stop. Release pedal quickly and do not drag brakes. Repeat four or five times.
At higher speeds engage brake pedal to slow car without coming to a complete stop. Release pedal quickly and do not drag brakes. Repeat five times.
At or near race speed engage brake pedal to slow car without coming to a complete stop. Release pedal quickly and do not drag brakes. Repeat three times. Allow a few seconds between brake engagements while car is in motion.
Do not hold brake pedal. Park car for approximately 20 minutes or until brake rotors are completely cool to the touch.
If during the above steps the brake pedal becomes soft or brake fade is noticed, park the car immediately for approximately 20 minutes. Do not hold brake pedal.

Important reminders:

Do not attempt to use badly worn or damaged rotors with new brake pads.
Do not drag brakes while car is moving during break-in procedure.
Do not engage pedal while car is stopped at any time following the break-in procedure.
Upon completing the procedure, allow the brake system to completely cool before racing.
Applying the pedal a few times before the start of the race will allow the brake pads to heat up before attempting to reach race speeds.
Clean a used rotor surface with fine sand paper or steel wool, rinse with water, dry and install before bedding new pads.
Some forms of racing don't allow time for the proper break-in procedure to be performed. However, it is still very important to attempt to perform at least the core of the procedure: slow heat build up and complete cool down.

This procedure works for any pad that I have used on other cars, from OEM types to performance pads. It's probably the most important thing you can do besides making sure the calipers and pins are functioning properly. IMO, even rotor choice is way less important than properly bedding in the pads.

 

Thanks for posting.

That is true. So many people play the rotors have to be bad deal that often they spend a lot of money on expensive drilled, dimpled and slotted rotors only to get the same conditions.

Also with pads the higher more expensive pads use less cheap fillers. Fillers are often what causes a uneven grip surface on a rotor. Add that to not seating them is and it created the shudder.

This is what happens if you fail to seat pads. Your rotor surface is just steel and the pad material is not even on the surface. You make hard stops from the freeway off ramp or in traffic. the fillers and material stick to the place where you stop and the pad material sticks to the spot the caliper clamps at a stop.

Now that one spot has more material on it vs the rest and when you stop the car will feel like a warped rotor with uneven stopping force.

Note if the rotor was warped the caliper is foating and it would follow the rotor anyways.

Bedding in the pads makes a even surface where material will not build in one spot creating the issue.

Few tech seat in pads and they are not done on cars from the factory at delivery. It is up to the owner to do so in most cases. In fact I would say even most here who have changed pads themselves have not done this based on the comments I have read.

This is something even good long time mechanics fail to do as in years past the pads were not as sensitive. Today it is a must or you could have issues you may have a hard time resolving.

 

ATE rotors with Hawk pads.

 

When I do brakes it will be Bendix rotors and either Hawk or EBC Red. It may come down to what we have in stock. I have used both and have had good results with each.

If we don't have them Hawk is only about 20 Miles from me so I can get them fast if we don;t have them.

 

Brakes were pulsating and dealer turned rotors at 6,000 only lasted a few weeks At 8,000 miles I installed drilled and slotted rotors. Have 130,000 miles now, never any pulsating. I do hear a slight noise from rotors do to the slots and holes. Went on a trip to Ca. and the mountain grades in Utah and Colo. never bothered them. They sure worked great for me.

 

Just don't confuse the holes and slots with solving the issue. Holes are just cosmetic. Slots can clean a pad and rotor surface. Too many people solve the real issue and credit the wrong part.

Often when they put these rotors on they also install better quailty pads on the vehicle and they solve the issue. Also they miss the issue of caliper issues too.

The drilled ones do look nice but that is all they do.

 

Does anyone know if this FNC process includes Factory replacements yet?

 

Brake threads always contain some level of misunderstanding about holes, slots and warpage.

Holes and slots in rotors are ALL cosmetic. A long time ago, drilling and slotting rotors was done by racers as a strategy to mitigate the effects of brake pads "outgassing" when they got really hot. Today, it's seldom necessary as improved brake pad technology and reduced problems with outgassing

The performance aftermarket, capitalizing on some enthusiasts beliefs that if it's done by racers it must be good for the street, has convinced many that drilled rotors/slotted rotors are necessary to address outgassing. Also, some believe the slots "clean" pads and rotors. Fact is, if the grooves/slots are machined such that they'll "clean" the pads then they are done wrong. If you absolutely must groove rotors, they need to be machined by someone who knows how to make the grooves such that they do not remove or scrape the pads. The grooves cannot "clean" the rotors as they are IN the rotors. Bottom line: rotor grooving was developed as another way to deal with outgassing but do it in a way that doesn't remove as much material from the rotor as does drilling. It follows that is your truly believe you need a hedge against brake pad outgassing then groove rather than drill your rotors.

As for warpage, many cases of "warped" rotors causing "pulsations" are not really warpage. Some rotors, depending on material and useage, develop "hard spots" or deposits of cementite in the cast iron. Those deposits have a different coefficient of friction than does normal iron. As the pad sweeps across areas of varying friction, the deceleration the brake generates changes. The rapidly varying change in friction causes a rapid variance in braking and that sets up a vibration with a fore/aft vector. If both sides of the car have the problem, the variance can either be in synch or out of synch on a per side basis and if it's partially or all out of synch, the steering wheel will shudder. You'll actually have shudder in two directions, fore/aft and left/right. Our bodies have an easier time feeling the side to side rather than the fore/aft vibration and, in fact, our brains fool us sometimes with the fore/aft shaking.

The end result which you may feel is two things. The steering wheel may shudder under braking and, if the brakes are applied, just as the car rolls to a stop, the variance in friction and decel sets up a rapid fore/aft sort of shaking feeling.

All this is not to say rotors do not warp. They can and when they do you'll get steering wheel shudder under braking and you may get brake pedal pulsation. You can measure the rotor and determine if it's warped or not. If you've got brake shudder/pedal pulsation and you measure warpage then...the rotors are warped, but if you've got brake shudder but no warpage is measured, then hard spots or cementite is probable.

Machining the rotors can temporarily eliminate the problem and dealers love to do it because then they don't have to replace the rotors under warranty.

The problem with machining rotors is most of these problems which cause "pulsations" and "shudder" are caused or at least made worse by heat. When you machine the rotor, you remove material. That reduces the rotor's mass and it is mass which is your heat sink, ie: the more you machine the rotors and remove iron, the more liable they become to develop heat-related problems.

Machining or "turning" the rotors may actually be more effective if the rotor is truly warped but only warped slightly. If the rotor is warped a lot and you have to machine it to near minimum thickness to clean it up you might as well scrap it and buy new ones.

If the rotor has hard spots, machining may temporarily solve the problem, but it's likely the problem will come back.

When you get down to it, crappy cast iron used by OEs is one reason there is so much trouble with brake rotors. Rotors which are good designs and use good materials seldom warp except under the most extreme conditions. Rotors which are poor designs (lacking adequate mass) or poor materials (crappy cast iron) a likely to warp, even under normal conditions.