rotora rotors - 2nd thoughts
#1
rotora rotors - 2nd thoughts
I replaced my rotors and pads with rotora rotors / pads at 90kmiles. Now I am at 103K and they are warped already. Every time I brake, the steering shakes non-stop. I followed the break in procedure very carefully. I don't I can turn these rotors since they are slotted.
#4
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How did you break them in originally? You can try and re bed the pads again. You can also turn slotted rotors. Some shops do do it. For the rotors to last that long and then warp though you must have done something extreme to warp them if they are in fact warped. Any ridiculous braking like 125 to 30 mph stop?
#5
Originally Posted by Excelerate
How did you break them in originally? You can try and re bed the pads again. You can also turn slotted rotors. Some shops do do it. For the rotors to last that long and then warp though you must have done something extreme to warp them if they are in fact warped. Any ridiculous braking like 125 to 30 mph stop?
When I first put them on, everything was fine. I took it easy with them for the first 1000 miles. No hard braking at all. I commute to work everyday, mostly all highway never really need to brake much. Hardly gone over 80mph. Couple of weeks ago, I started getting the pulsation feeling when pressing the brakes. Everyday it got a little bit worst and now, the steering wheel wobbles constantly. I will check to see if anyone can turn slot rotors.
#7
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From: www.ExceleratePerformance.com
Originally Posted by TypeSDragon
When I first put them on, everything was fine. I took it easy with them for the first 1000 miles. No hard braking at all. I commute to work everyday, mostly all highway never really need to brake much. Hardly gone over 80mph. Couple of weeks ago, I started getting the pulsation feeling when pressing the brakes. Everyday it got a little bit worst and now, the steering wheel wobbles constantly. I will check to see if anyone can turn slot rotors.
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#8
^ That's not what it says to do when I bought EBC pads. It says to drive regularly, and not to brake hard for the first 200-500 miles. Wait, I guess taht would be the same thing haha nevermind.
#9
Originally Posted by MurkyRiversTL
^ That's not what it says to do when I bought EBC pads. It says to drive regularly, and not to brake hard for the first 200-500 miles. Wait, I guess taht would be the same thing haha nevermind.
Have your wheels been off lately? where the rims torqued properly?
#10
Do as Excellerate says and rebed the pads.
Driving them gently at first is good- THEN do a bed in
High performance brakes must be driven harder than OE brakes- in order for
them to come up the operating temp across the surface of the pad
Since you drive them gently most of the time- a glaze has formed and
by heating the pads as directed above- the repeated SLOW DOWN- NOT STOP
with increasing pedal effort each time, that causes a proper transfer of layer of pad material to the rotor- this makes for better braking and should clear the shimmy shake problem
Make sure to drive around without using the brakes for 20 minutes to let the rotors cool completely before you do a full stop and then park.
If they are still hot- you will make a new problem that must then be cleaned.
Good Luck
Driving them gently at first is good- THEN do a bed in
High performance brakes must be driven harder than OE brakes- in order for
them to come up the operating temp across the surface of the pad
Since you drive them gently most of the time- a glaze has formed and
by heating the pads as directed above- the repeated SLOW DOWN- NOT STOP
with increasing pedal effort each time, that causes a proper transfer of layer of pad material to the rotor- this makes for better braking and should clear the shimmy shake problem
Make sure to drive around without using the brakes for 20 minutes to let the rotors cool completely before you do a full stop and then park.
If they are still hot- you will make a new problem that must then be cleaned.
Good Luck
#12
Originally Posted by pmptx
Not going to glaze a pad on a slotted rotor, the rotor should be shaving the pad slighly with each stop.
#15
TypeSDragon, my first pair of Rotora slotted fronts were also warped after been through one set of Axxis Ultimate pads and 1/3 of the way throught a set of EBC green pads. I did the stop-go break-in/bed-in procedures when they were new.
Same as you, no local shop can machine slotted rotors. Deglazing them got rid of the grab-release, grab-release jerking movement whenever I applied the brakes, but not the warpage.
So I bought a new set of Rotora slotted fronts and new EBC greens F/R, because I want to keep my Rotora rears which were still reasonably good. This time I didn't do the stop-go break-in thing, but to go easy on them for the first few hundred kms. I'll wait and see how long before the front will warp again, so I can determine how necessary is the stop-go break-in recommendation.
Same as you, no local shop can machine slotted rotors. Deglazing them got rid of the grab-release, grab-release jerking movement whenever I applied the brakes, but not the warpage.
So I bought a new set of Rotora slotted fronts and new EBC greens F/R, because I want to keep my Rotora rears which were still reasonably good. This time I didn't do the stop-go break-in thing, but to go easy on them for the first few hundred kms. I'll wait and see how long before the front will warp again, so I can determine how necessary is the stop-go break-in recommendation.
#17
Thanks for everyone's input. Very informative! I just went out to rebed the brakes, took a 1/2 hr break from work just to do this. I will do it again after work. It is sometimes difficult accelerating and deaccelerating on local streets. There was a cop hiding in the corner when I reach an intersection earlier. If this doesn't workout, I will go back to Irotors. I had these last time and they lasted more than 75K before I had to replace them. I am pretty sure Kris agrees with me on this one.
#18
Look at www.racingbrake.com and MrHeelToe in our sponsor forums
Heat treated
Special Alloys
Unique curved cooling vanes
The tech in brake rotors
Heat treated
Special Alloys
Unique curved cooling vanes
The tech in brake rotors
#21
Originally Posted by Studio
Get some brembo blanks. Problem solved.
I've had rotoras for a while now and they've been the best I've had so far...I've had KVR cross-drilled, aftermarket blanks, oem blanks, rotoras.. etc...
The brakes on the TL are simply too small... they overheat too often and they warp...
#22
Originally Posted by @cUr@-TL
That's not gonna solve anything. brembo blanks arent any better...
I've had rotoras for a while now and they've been the best I've had so far...I've had KVR cross-drilled, aftermarket blanks, oem blanks, rotoras.. etc...
The brakes on the TL are simply too small... they overheat too often and they warp...
I've had rotoras for a while now and they've been the best I've had so far...I've had KVR cross-drilled, aftermarket blanks, oem blanks, rotoras.. etc...
The brakes on the TL are simply too small... they overheat too often and they warp...
#23
Originally Posted by dvsxlt247
Ill Take your word on that. But if this is true, then whats the point of me buying these rotoras then anyways. For that i might as well ride my stock rotors SHAKING LIKE AN EARTHQUAKE and all, all the way until its deff time to get new stock rotors or whatever. Someone just remind me that my purchase of the rotoras which ill be getting in the mail soon was worth the buy because the performance really is better with the slotted rotors.
well to me the rotoras are worth it because the slots give them more chance of cooling down, plus the "e-coating" is nice and keeps rust away...
i was very satisfied with them, personnaly.
#25
Lifetime warranty hahahahahah
They replaced my lifetime pads 4 times in 3 years- what a great deal!
The young and uneducated consumers in the group
I am telling you from a scientific point of view as a pilot, race car builder and driver
that heat is extracted from the rotor FAR better with the www.racingbrake.com one piece replacements- the ultimate way to build a brake rotor.
get educated and solve your braking issues for good
They replaced my lifetime pads 4 times in 3 years- what a great deal!
The young and uneducated consumers in the group
I am telling you from a scientific point of view as a pilot, race car builder and driver
that heat is extracted from the rotor FAR better with the www.racingbrake.com one piece replacements- the ultimate way to build a brake rotor.
get educated and solve your braking issues for good
#26
Originally Posted by 01tl4tl
Edward
Did you do it backwards
Stop go stop go?
Its GO fast, slow down but dont stop
go fast, slow down
go fast slow down
cool by driving without using brakes
Did you do it backwards
Stop go stop go?
Its GO fast, slow down but dont stop
go fast, slow down
go fast slow down
cool by driving without using brakes
http://www.powerbrake.co.za/downloads/tech_02_bedin.pdf
#27
I have power slots and they are pretty similar to the rotoras. I did the break in as described by the EBC pads and 10k miles later everything is still great. I think the key is actually getting to a road where you can do it because in most traffic it can't be done without risk. I had to drive close to red rock mountain here to do it, you also need a long stretch of road to do it properly.
#28
Originally Posted by dvsxlt247
Ill Take your word on that. But if this is true, then whats the point of me buying these rotoras then anyways. For that i might as well ride my stock rotors SHAKING LIKE AN EARTHQUAKE and all, all the way until its deff time to get new stock rotors or whatever. Someone just remind me that my purchase of the rotoras which ill be getting in the mail soon was worth the buy because the performance really is better with the slotted rotors.
This is the major motivation for me to buy slotted rotors and matching high performance brake pads. The benefit of having slots is that they cut into the pads and clean out the pads' contact surface, thereby increasing friction and so braking performance. The harder pad compound also helps. I'll stay away from drilled rotors because of their tendency to crack and with less mass to dissipate heat.
#29
Originally Posted by Billy Sacco
I have power slots and they are pretty similar to the rotoras. I did the break in as described by the EBC pads and 10k miles later everything is still great. I think the key is actually getting to a road where you can do it because in most traffic it can't be done without risk. I had to drive close to red rock mountain here to do it, you also need a long stretch of road to do it properly.
#31
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From: www.ExceleratePerformance.com
You need not be worried about ROTORA rotors. They are of great quality and they are durable. There are many many members running these discs without a single issue and for a number of miles. The slots will help by constantly cutting into the pad and preventing the pad from glazing. There is better dissipation of heat and therefore less chance of warping than the stock rotors.
Keep this in mind. The Acura CL/TL disc is ROTORA's #1 selling slotted disc. So imagine how many are out there. And what do you see? A few posts a year about someone warping their rotors? And I'm not saying the OP did anything wrong but think of how many ppl abuse their brakes or dont' torque the lugs down properly or in the correct pattern or don't bed the pads properly And yet there are only a few cases a year. ROTORA rotors are high quality rotors. They are very functional and combined with a good pad they will improve braking. I noticed a substantial difference after I installed them on my CL-S.
Keep this in mind. The Acura CL/TL disc is ROTORA's #1 selling slotted disc. So imagine how many are out there. And what do you see? A few posts a year about someone warping their rotors? And I'm not saying the OP did anything wrong but think of how many ppl abuse their brakes or dont' torque the lugs down properly or in the correct pattern or don't bed the pads properly And yet there are only a few cases a year. ROTORA rotors are high quality rotors. They are very functional and combined with a good pad they will improve braking. I noticed a substantial difference after I installed them on my CL-S.
#32
I have to agree with Josh/Excellerate- on the point of lug torque being a major
issue with brake rotor warpage.
People need to understand the dynamic involved (putting on Mr Science coat)
Look at the rotor hub- it is small and has holes drilled in it for the wheel lugs.
Now that part goes against the axle hub which drives the wheels
The wheel goes on and the bolts go into the middle of all of this
Now the stress loads of each wheel lug need to be gently and EVENLY applied when the wheel is bolted on. The lugs actually hold everything behind them securley to the vehicle.
If you blast on one lug then zap the others and go blast the first one again
Congratulations- thats a great way to warp rotors and have no known lug torque value.
If you want to do it really right - just short of OCD, but as we do it in the race car
Place wheel in position
Install bottom lug snug while holding wheel inplace
Then the top snugged
Now the sides.
Rotate tire to make sure everything is centered
Tighten each lug 20 ft lbs at a time in the star pattern
Repeat until 80 ft lbs or spec for your rims
Keep those expensive rotors safe from chump tire changers hands
Do everything you can yourself- armed with knowledge and TORQUE WRENCH
issue with brake rotor warpage.
People need to understand the dynamic involved (putting on Mr Science coat)
Look at the rotor hub- it is small and has holes drilled in it for the wheel lugs.
Now that part goes against the axle hub which drives the wheels
The wheel goes on and the bolts go into the middle of all of this
Now the stress loads of each wheel lug need to be gently and EVENLY applied when the wheel is bolted on. The lugs actually hold everything behind them securley to the vehicle.
If you blast on one lug then zap the others and go blast the first one again
Congratulations- thats a great way to warp rotors and have no known lug torque value.
If you want to do it really right - just short of OCD, but as we do it in the race car
Place wheel in position
Install bottom lug snug while holding wheel inplace
Then the top snugged
Now the sides.
Rotate tire to make sure everything is centered
Tighten each lug 20 ft lbs at a time in the star pattern
Repeat until 80 ft lbs or spec for your rims
Keep those expensive rotors safe from chump tire changers hands
Do everything you can yourself- armed with knowledge and TORQUE WRENCH
#33
I too agree that properly torqueing the wheel nuts is important. But I have learnt about that proper torque trick from the Integra forum back in 1992, when I was driving a heavily modded Integra. Since then, everytime someone (including Acura dealership) removes and reinstalls my wheels, I'll go striaght home and retorque all nuts to the proper 80 ft-lbs in the proper tightening pattern before I do any serious driving. No exception. I guess this takes improper wheel nut torqueing out from explaining my case of Rotora rotor warpage.
Invest in a high quality torque wrench, and check how uniform wheel shops and dealerships torque the wheel nuts. You'll be surprise by how hard some nuts are torqued and how loose others are. This is a recipe for rotor warpage for those fast drivers.
I must also give credit to Rotora because my Rotora's have lasted many thousand kms of hard driving, having gone through one and ~1/3 set of performance brake pads. The first set was worn right down to the screeching warning clips. Even when warped in my case, I only have small shaking movement from the steering wheel during braking, in contract to some warped OEM Honda rotors that I have experienced which shaked so violently that my hands hurt from grabbing the steering wheel. Paint finish is another story.
Invest in a high quality torque wrench, and check how uniform wheel shops and dealerships torque the wheel nuts. You'll be surprise by how hard some nuts are torqued and how loose others are. This is a recipe for rotor warpage for those fast drivers.
I must also give credit to Rotora because my Rotora's have lasted many thousand kms of hard driving, having gone through one and ~1/3 set of performance brake pads. The first set was worn right down to the screeching warning clips. Even when warped in my case, I only have small shaking movement from the steering wheel during braking, in contract to some warped OEM Honda rotors that I have experienced which shaked so violently that my hands hurt from grabbing the steering wheel. Paint finish is another story.
#34
"Since then, everytime someone (including Acura dealership) removes and reinstalls my wheels, I'll go striaght home and retorque all nuts to the proper 80 ft-lbs in the proper tightening pattern before I do any serious driving. No exception. I guess this takes improper wheel nut torqueing out from explaining my case of Rotora rotor warpage."
UMMMM NO it doesnt!
If the lugs are put on with uneven distribution of torque/pressure, thats how the warpage occurs, initial stress loading.
The fact that everytime- you must retorque the wheels means they were not put on correctly.
Fixing it at home does not withdraw the stress already applied
UMMMM NO it doesnt!
If the lugs are put on with uneven distribution of torque/pressure, thats how the warpage occurs, initial stress loading.
The fact that everytime- you must retorque the wheels means they were not put on correctly.
Fixing it at home does not withdraw the stress already applied
#35
Originally Posted by 01tl4tl
"Since then, everytime someone (including Acura dealership) removes and reinstalls my wheels, I'll go striaght home and retorque all nuts to the proper 80 ft-lbs in the proper tightening pattern before I do any serious driving. No exception. I guess this takes improper wheel nut torqueing out from explaining my case of Rotora rotor warpage."
UMMMM NO it doesnt!
If the lugs are put on with uneven distribution of torque/pressure, thats how the warpage occurs, initial stress loading.
The fact that everytime- you must retorque the wheels means they were not put on correctly.
Fixing it at home does not withdraw the stress already applied
UMMMM NO it doesnt!
If the lugs are put on with uneven distribution of torque/pressure, thats how the warpage occurs, initial stress loading.
The fact that everytime- you must retorque the wheels means they were not put on correctly.
Fixing it at home does not withdraw the stress already applied
If this is the case, then it doesn't really matter what rotors (such as Brembo, Rotora, etc.) you put on because they are prone to warpage due to our reliance on mechanics to torque them evenly. Even if a mechanic promise you to hand-torque the wheel nuts evenly, there is no guarantee that he is carefully enough to tighten all 20 nuts to exactly 80 ft-lbs, unless it's his car.
#36
Well to start with
Auto assembly plants use a special multi head TORQUE spec tool to install all the lugs evenly at the same time. 5 at once- amazing to watch!
Since we do not have that tool, the best we can do is 20 lbs at a time method
Dont you watch How Its Made?
If was an imaginary problem- why do some many have issues- especially after rotation or new tires?
High quality rotors are less subject to this- but all are suseptible to a point- some more than others
Since I am the only one to deal with my wheels, or they are done under my direct- standing over his shoulder- observation, I have less issues.
I have to teach this to tire guys all the time.
When I ran a shop for $$$$ cars- this is how we taught the guys to do it.
Is todays tech aware?- probably not, so its up to you to be proactive protecting your car.
And a good shop will require the tech to use a torque wrench to check the lugs
Its a liabilty/Insurance issue- wheel fall off- they buy your car
Sadly, most will check after using the air gun, and they hear click- ok all good.
Wrong- bring up tension until CLICK- all they know for sure is yours are over 80 and they wont fall off- send you down the road
Want real car care by Pro- find a race shop that works on imports- treat your car
in a different mindset than the average place.
Auto assembly plants use a special multi head TORQUE spec tool to install all the lugs evenly at the same time. 5 at once- amazing to watch!
Since we do not have that tool, the best we can do is 20 lbs at a time method
Dont you watch How Its Made?
If was an imaginary problem- why do some many have issues- especially after rotation or new tires?
High quality rotors are less subject to this- but all are suseptible to a point- some more than others
Since I am the only one to deal with my wheels, or they are done under my direct- standing over his shoulder- observation, I have less issues.
I have to teach this to tire guys all the time.
When I ran a shop for $$$$ cars- this is how we taught the guys to do it.
Is todays tech aware?- probably not, so its up to you to be proactive protecting your car.
And a good shop will require the tech to use a torque wrench to check the lugs
Its a liabilty/Insurance issue- wheel fall off- they buy your car
Sadly, most will check after using the air gun, and they hear click- ok all good.
Wrong- bring up tension until CLICK- all they know for sure is yours are over 80 and they wont fall off- send you down the road
Want real car care by Pro- find a race shop that works on imports- treat your car
in a different mindset than the average place.
#37
Well the way you put it makes it appear very disturbing : "If the lugs are put on with uneven distribution of torque/pressure, thats how the warpage occurs, initial stress loading."
Like I said before, even factory trained mechanics in Acura dealerships don't tighten all nuts to the exact torque spec. All you members can check it next time after tire rotations or brake services. Have you also checked it yourself ? So even factory trained mechanics can't do it right all the times, how can one expect the regular tire and wheel shops (without the amazing multi-head torqueing tool) to do it correctly ?
One can teach the guys there to do it right, but will they all have the time and heart to do what you told them to is another question, especially most mechanics don't like being told what to do. Most shops don't allow customers in the bay, so there is no way of monitoring their work on your car.
It ain't no imaginary problem if it's true that even screwing the nuts on with uneven torque may warp the rotors.
Like I said before, even factory trained mechanics in Acura dealerships don't tighten all nuts to the exact torque spec. All you members can check it next time after tire rotations or brake services. Have you also checked it yourself ? So even factory trained mechanics can't do it right all the times, how can one expect the regular tire and wheel shops (without the amazing multi-head torqueing tool) to do it correctly ?
One can teach the guys there to do it right, but will they all have the time and heart to do what you told them to is another question, especially most mechanics don't like being told what to do. Most shops don't allow customers in the bay, so there is no way of monitoring their work on your car.
It ain't no imaginary problem if it's true that even screwing the nuts on with uneven torque may warp the rotors.
#38
First I agree with you completely - People should be very disturbed
and concerned anytime some else must touch their car.
Hopefully this thread is educating members and they go forth more aware
Lets starts with factory trained mechanics- training is about car systems- ABS-electrical-fuel-smog-etc, not the smart way to put on tires. Various skill levels and backgrounds are working today, good luck even getting the tire pressure where you want it!
Overseeing the work is simple and talking to the Manager who can EDUCATE the Techs-
a new skill and procedure.
Lets use a different example
Who here had replaced an intake mainfold on a V-8 engine - especially an aluminum like Edelbrock or similar?
Theres like 12 or 16 bolts in 2 bolt segments, that MUST be tighted down 5 lbs at a time in a crazy cross bolt cross torsional load spreading pattern to 25 lbs then left overnight and retorqued the same way and they will need it. Then again in 500 miles.
Does anyone here recheck the wheels after 500 miles? I do, but I am also a pilot and racer so a different approach to survival. For that matter on track days they get retorqued after every on track session - thats 20 -30 minutes flat out and the wheels do loosen up.
Or oil pan bolts- same thing, specific pattern in the repair book, and every fastner on the car has a specified torque setting.
Imagine the lugs holding the wheel to the rotor to the axle and it makes sense to do it right.
So yes- I feel the way I was taught many years ago for BMWs with $$$ balanced on the car wheels- you have to put them back on with the marks or ruin the balance.
I also make sure the referance dots on my tires get mounted properly.
Too many places employ the cheapest, not the brightest workers.
There are techs who can snug the lugs a bit at a time with an air gun by feel- and check them when done.
With all that said, Have you Edward- gone back at a safe time like night and done the full bedding procedure as described before by Ecellerate, you may even have to do it twice because attempt the other day where you had to do a full stop- that loads the stuff in one place and must be fully removed.
After doing the procedure and letting the rotors cool while driving- then park and in 15 minutes should be ready to go. Retest for shudder under braking
Before warped rotors can be considered- they must be measured with a dial indicator run-out guage which measures movement laterally while the rotor spins slowly
Anything else is someones guess whats wrong.
Testing and procedure are solutions
Good Luck!~
and concerned anytime some else must touch their car.
Hopefully this thread is educating members and they go forth more aware
Lets starts with factory trained mechanics- training is about car systems- ABS-electrical-fuel-smog-etc, not the smart way to put on tires. Various skill levels and backgrounds are working today, good luck even getting the tire pressure where you want it!
Overseeing the work is simple and talking to the Manager who can EDUCATE the Techs-
a new skill and procedure.
Lets use a different example
Who here had replaced an intake mainfold on a V-8 engine - especially an aluminum like Edelbrock or similar?
Theres like 12 or 16 bolts in 2 bolt segments, that MUST be tighted down 5 lbs at a time in a crazy cross bolt cross torsional load spreading pattern to 25 lbs then left overnight and retorqued the same way and they will need it. Then again in 500 miles.
Does anyone here recheck the wheels after 500 miles? I do, but I am also a pilot and racer so a different approach to survival. For that matter on track days they get retorqued after every on track session - thats 20 -30 minutes flat out and the wheels do loosen up.
Or oil pan bolts- same thing, specific pattern in the repair book, and every fastner on the car has a specified torque setting.
Imagine the lugs holding the wheel to the rotor to the axle and it makes sense to do it right.
So yes- I feel the way I was taught many years ago for BMWs with $$$ balanced on the car wheels- you have to put them back on with the marks or ruin the balance.
I also make sure the referance dots on my tires get mounted properly.
Too many places employ the cheapest, not the brightest workers.
There are techs who can snug the lugs a bit at a time with an air gun by feel- and check them when done.
With all that said, Have you Edward- gone back at a safe time like night and done the full bedding procedure as described before by Ecellerate, you may even have to do it twice because attempt the other day where you had to do a full stop- that loads the stuff in one place and must be fully removed.
After doing the procedure and letting the rotors cool while driving- then park and in 15 minutes should be ready to go. Retest for shudder under braking
Before warped rotors can be considered- they must be measured with a dial indicator run-out guage which measures movement laterally while the rotor spins slowly
Anything else is someones guess whats wrong.
Testing and procedure are solutions
Good Luck!~
#39
And I want to be clear- when discussing the warp factor and torque
I am referring to the mauling grueling technique of a hi powered air gun without a pressure setting of 120 psi on it BLASTING on one lug then another and finally the first one again
The most extreme example of how this can easily cause a problem,
you can bend rims that way too!
So if its important to spread the load out evenly and slowly on most every other part on the car during repair assembly- why not the primary part of the system too
I am referring to the mauling grueling technique of a hi powered air gun without a pressure setting of 120 psi on it BLASTING on one lug then another and finally the first one again
The most extreme example of how this can easily cause a problem,
you can bend rims that way too!
So if its important to spread the load out evenly and slowly on most every other part on the car during repair assembly- why not the primary part of the system too
#40
I have Rotoras and EBC Green Stuff pads installed (by my Acura dealer). I have never torqued the wheels, I've never stood over anyone and watched them to make sure they do it properly. My rotors are not warped.