[ZR1] Carbon Ceramic Rotor Vibration fix (video)
08-21-2019, 12:43 AM
#1
Drifting
Thread Starter
Carbon Ceramic Rotor Vibration fix (video)
I've been attacking this issue for about a month now and finally nailed down a procedure that involves balancing the wheel and rotor together utilizing a wheel spacer and tire balancing machine. It took me the greater part of a few months to even get through all the threads only to have my head spinning from all the suggestions of what the dealer should do to help us out. However, now that (most of) our ZR1s aren't under warranty anymore, this issue pretty much has left as fend for ourselves. I tried a number of different methods with limited success but finally came across one that worked.
This thread is meant for new buyers that are just now discovering this issue and don't know where to start on a fix. I know I would have loved to have had something as straight forward when I started sifting through the endless threads on the topic, so that was my motivation for making it. There's a lot of redundancy in the video and repeating steps but that's only to drive home how important it is to keep everything indexed. Most of the credit for the info from this video is a culmination of everyone's input and all the threads I've sifted through. While I made this video, it's literally just a regurgitation of everything I've learned through here. For CorvetteForum, by CorvetteForum. Thanks guys, and hope this helps out some folks.
This thread is meant for new buyers that are just now discovering this issue and don't know where to start on a fix. I know I would have loved to have had something as straight forward when I started sifting through the endless threads on the topic, so that was my motivation for making it. There's a lot of redundancy in the video and repeating steps but that's only to drive home how important it is to keep everything indexed. Most of the credit for the info from this video is a culmination of everyone's input and all the threads I've sifted through. While I made this video, it's literally just a regurgitation of everything I've learned through here. For CorvetteForum, by CorvetteForum. Thanks guys, and hope this helps out some folks.
The following 8 users liked this post by Stavesacre21:
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and 3 others liked this post.
08-26-2019, 05:58 AM
#7
Great post....informative video.....you did a good job
I dont even own a ZR1 (yet) and it had me thinking about finding out how "in balance" my steel rotors are on my C6Z and other performance toys I see some solid MPH in.
When I install them (the rotors) I always wonder how much trouble the manufacturer went though (if any) to get them right.
That adapter situation makes this all to easy to verify now and is well worth the cost off buying four to make it easier and faster at the balance shop. Keeping an eye on the tire and rotor phasing is easy once this is done.
Like I said....Im not even experiencing the issue you needed to fix but found the video well done and has my gears turning.
I bet your car feels incredible at 140 or more MPH now.....
I would rather be focusing on the road than focusing on the bad vibrations in my steering wheel adding to the voice of reason in my head telling me to lift.....LOL
Kudos!
-Tony
PS.....How much weight did your wheels take? Did you keep track of that? I imagine if it was that noticeable (the vibration) it had to be a fair bit to balance unless you got lucky and offset some rotor imbalance with wheel imbalance which I also thought about. If one wheel/rotor combo was asking for alot of weight I would unbolt it and move the rotor 180 degrees ish to see if it took alot less that way. I prefer the least weight possible to still get a good balance and will move the tire on a rim at times if one of them is asking for alot more than the others. The rotor gives you something else in the mix to play with in an attempt to reduce the weights required.
I dont even own a ZR1 (yet) and it had me thinking about finding out how "in balance" my steel rotors are on my C6Z and other performance toys I see some solid MPH in.
When I install them (the rotors) I always wonder how much trouble the manufacturer went though (if any) to get them right.
That adapter situation makes this all to easy to verify now and is well worth the cost off buying four to make it easier and faster at the balance shop. Keeping an eye on the tire and rotor phasing is easy once this is done.
Like I said....Im not even experiencing the issue you needed to fix but found the video well done and has my gears turning.
I bet your car feels incredible at 140 or more MPH now.....
I would rather be focusing on the road than focusing on the bad vibrations in my steering wheel adding to the voice of reason in my head telling me to lift.....LOL
Kudos!
-Tony
PS.....How much weight did your wheels take? Did you keep track of that? I imagine if it was that noticeable (the vibration) it had to be a fair bit to balance unless you got lucky and offset some rotor imbalance with wheel imbalance which I also thought about. If one wheel/rotor combo was asking for alot of weight I would unbolt it and move the rotor 180 degrees ish to see if it took alot less that way. I prefer the least weight possible to still get a good balance and will move the tire on a rim at times if one of them is asking for alot more than the others. The rotor gives you something else in the mix to play with in an attempt to reduce the weights required.
Last edited by Tony @ Mamo Motorsports; 08-26-2019 at 06:07 AM.
08-26-2019, 12:31 PM
#9
Great post....informative video.....you did a good job
I dont even own a ZR1 (yet) and it had me thinking about finding out how "in balance" my steel rotors are on my C6Z and other performance toys I see some solid MPH in.
When I install them (the rotors) I always wonder how much trouble the manufacturer went though (if any) to get them right.
That adapter situation makes this all to easy to verify now and is well worth the cost off buying four to make it easier and faster at the balance shop. Keeping an eye on the tire and rotor phasing is easy once this is done.
Like I said....Im not even experiencing the issue you needed to fix but found the video well done and has my gears turning.
I bet your car feels incredible at 140 or more MPH now.....
I would rather be focusing on the road than focusing on the bad vibrations in my steering wheel adding to the voice of reason in my head telling me to lift.....LOL
Kudos!
-Tony
PS.....How much weight did your wheels take? Did you keep track of that? I imagine if it was that noticeable (the vibration) it had to be a fair bit to balance unless you got lucky and offset some rotor imbalance with wheel imbalance which I also thought about. If one wheel/rotor combo was asking for alot of weight I would unbolt it and move the rotor 180 degrees ish to see if it took alot less that way. I prefer the least weight possible to still get a good balance and will move the tire on a rim at times if one of them is asking for alot more than the others. The rotor gives you something else in the mix to play with in an attempt to reduce the weights required.
I dont even own a ZR1 (yet) and it had me thinking about finding out how "in balance" my steel rotors are on my C6Z and other performance toys I see some solid MPH in.
When I install them (the rotors) I always wonder how much trouble the manufacturer went though (if any) to get them right.
That adapter situation makes this all to easy to verify now and is well worth the cost off buying four to make it easier and faster at the balance shop. Keeping an eye on the tire and rotor phasing is easy once this is done.
Like I said....Im not even experiencing the issue you needed to fix but found the video well done and has my gears turning.
I bet your car feels incredible at 140 or more MPH now.....
I would rather be focusing on the road than focusing on the bad vibrations in my steering wheel adding to the voice of reason in my head telling me to lift.....LOL
Kudos!
-Tony
PS.....How much weight did your wheels take? Did you keep track of that? I imagine if it was that noticeable (the vibration) it had to be a fair bit to balance unless you got lucky and offset some rotor imbalance with wheel imbalance which I also thought about. If one wheel/rotor combo was asking for alot of weight I would unbolt it and move the rotor 180 degrees ish to see if it took alot less that way. I prefer the least weight possible to still get a good balance and will move the tire on a rim at times if one of them is asking for alot more than the others. The rotor gives you something else in the mix to play with in an attempt to reduce the weights required.
Regarding the last bit there highlighted in red, FWIW the way I set these up initially is by using a static balancer. These are often used for balancing motorcycle wheels/tires and if you have access to one or are comfortable spending the additional money on one or simply want to fabricate something similar, it's a way to get a good initial rotor-to-wheel/tire index prior to dynamic balancing. Here's the one that I use for example:
This type of device will allow you to identify the heavy spot on each rotor by itself and then the heavy spot for each wheel/tire by itself (obviously you'll want to strip off any previous balancing weights from the wheel prior to doing any of this). Having documented the heavy spots, you can then assemble the rotor to the wheel using an orientation that offsets the heavy spots as much as possible. This should give you the best chance at success when dynamic balancing.
08-26-2019, 03:00 PM
#10
Drifting
Thread Starter
If you can get them both ACCURATELY balanced separately (AKA Aston Martin TSB), more power to you bro. Since the video was already 17 minutes, I didn't wanna go into more detail to tell the steps I took leading up to my final soluation, but i'll gladly share them here.
First of all, I DID try to balance the rotors separately apart from the wheels. However, getting to the point where you could do so was a huge challenge. First off, you need to understand what goes into attempting to mount and spin a rotor on a wheel balancer. Unlike a wheel (which the wheel machine is made to attach and balance), the rotor isn't able to simply be thrown on the machine, screw in the wingnut and balance it. The mounting pad, surface ~~or whatever you wanna call it~~ is too large in diameter (on a Hunter RoadForce 9700 balancing machine) to even put the rotor on. It's hard to explain in words but there is no way to get the rotor flush on that surface without a spacer to move that balancing surface back about an inch and a half. The rotor's bolts stick out and lay on the mounting pad and since the bolts on the rotor are NOT flush, that can't be used. Threw the spacer on and it sits flush on the mount now...yay! You have a new problem now. hub-centric spacers have lugs on them, and if you plan to balance the rotor alone, you now have the back surface flat...BUT it leaves you all the lugs sticking out the front of the rotors which will no longer allow the wingnut to be spun onto the rotor to tighten it down. Grrr.
Once I reached that point, I wasn't about to be defeated, so what did I do? I cut all 5 spacer lugs down to 5mm, so that they wouldn't stick out the front of the rotor. So now I was able to finally mount the rotor on the balancer. Finally spun them and it came back that 3 were 1/4oz off and 1 that was 1/2oz off. So I marked on the rotors their weights and the location of the imbalance. Followed the rest of the TSB down to the last letter perfectly. Balanced the wheels perfectly alone, indexed the rotor to the wheels and placed the temporary weights, balanced the wheels with the temporary weights then removed the weights and thought I was perfect and all ready to go. At this point I still had 4 days until my calipers arrived from powder coating so I thought "hey, I've still got time and the spacers so lets just bolt everything together and spin them all. They should all come out perfectly balanced, right?".
Wrong. Dead wrong. EVERY ONE OF THEM were off. No idea how, because I was absolutely 110% perfect on following every detail of the TSB. And it wasn't just a little. 2 of them were 1/2oz off, one was 3/4oz off and completely unexplainably, the last one was 1.75oz off! And the real kicker is that the weight adjustments weren't even at or 180 degrees to the place I marked as imbalance on the rotor. These aren't minor differences here. I went back and double then triple checked my numbers, my technique and every step I took to make sure I did it correct and found no fault in my process. That leaves ONE factor here, and it has to be the machine. These machines simply aren't set up to properly balance rotors. Should be simple and upfront, right? I thought so too, but it's the only explanation I have. I personally watched them do every step on the machine so it wasn't a simple case of "they were ignorant or unskilled". Everything was done right, the math didn't add up.
Now...all this said and done, if you would like to go to the trouble of balancing them both separately and just assume they will work together nicely, have at. For me, it didn't work. And the proof is in the pudding with this, as the car now rides smooth as glass at all speeds up to 120 (where I stopped pushing).
PS.....How much weight did your wheels take? Did you keep track of that?
I prefer the least weight possible to still get a good balance and will move the tire on a rim at times if one of them is asking for a lot more than the others. The rotor gives you something else in the mix to play with in an attempt to reduce the weights required.
If you read the novel I just wrote above, you'll find that it's hard for me to accurately say how out of weight they were, as I don't believe the wheel balancer was giving me accurate balance numbers with the rotors alone. Somewhere between 1/4 and 3/4 oz on 3 of them and one was between 3/4 and 1.75oz.
As Fulton mentioned, you can always do a static balance to at least get an idea of where they are out of balance, but the average joe isn't going to have one of these available to do that with. If you do have access to one, it will help to reduce the number of wheel weights needed so that you can appropriately counter-index the heavier side.
First of all, I DID try to balance the rotors separately apart from the wheels. However, getting to the point where you could do so was a huge challenge. First off, you need to understand what goes into attempting to mount and spin a rotor on a wheel balancer. Unlike a wheel (which the wheel machine is made to attach and balance), the rotor isn't able to simply be thrown on the machine, screw in the wingnut and balance it. The mounting pad, surface ~~or whatever you wanna call it~~ is too large in diameter (on a Hunter RoadForce 9700 balancing machine) to even put the rotor on. It's hard to explain in words but there is no way to get the rotor flush on that surface without a spacer to move that balancing surface back about an inch and a half. The rotor's bolts stick out and lay on the mounting pad and since the bolts on the rotor are NOT flush, that can't be used. Threw the spacer on and it sits flush on the mount now...yay! You have a new problem now. hub-centric spacers have lugs on them, and if you plan to balance the rotor alone, you now have the back surface flat...BUT it leaves you all the lugs sticking out the front of the rotors which will no longer allow the wingnut to be spun onto the rotor to tighten it down. Grrr.
Once I reached that point, I wasn't about to be defeated, so what did I do? I cut all 5 spacer lugs down to 5mm, so that they wouldn't stick out the front of the rotor. So now I was able to finally mount the rotor on the balancer. Finally spun them and it came back that 3 were 1/4oz off and 1 that was 1/2oz off. So I marked on the rotors their weights and the location of the imbalance. Followed the rest of the TSB down to the last letter perfectly. Balanced the wheels perfectly alone, indexed the rotor to the wheels and placed the temporary weights, balanced the wheels with the temporary weights then removed the weights and thought I was perfect and all ready to go. At this point I still had 4 days until my calipers arrived from powder coating so I thought "hey, I've still got time and the spacers so lets just bolt everything together and spin them all. They should all come out perfectly balanced, right?".
Wrong. Dead wrong. EVERY ONE OF THEM were off. No idea how, because I was absolutely 110% perfect on following every detail of the TSB. And it wasn't just a little. 2 of them were 1/2oz off, one was 3/4oz off and completely unexplainably, the last one was 1.75oz off! And the real kicker is that the weight adjustments weren't even at or 180 degrees to the place I marked as imbalance on the rotor. These aren't minor differences here. I went back and double then triple checked my numbers, my technique and every step I took to make sure I did it correct and found no fault in my process. That leaves ONE factor here, and it has to be the machine. These machines simply aren't set up to properly balance rotors. Should be simple and upfront, right? I thought so too, but it's the only explanation I have. I personally watched them do every step on the machine so it wasn't a simple case of "they were ignorant or unskilled". Everything was done right, the math didn't add up.
Now...all this said and done, if you would like to go to the trouble of balancing them both separately and just assume they will work together nicely, have at. For me, it didn't work. And the proof is in the pudding with this, as the car now rides smooth as glass at all speeds up to 120 (where I stopped pushing).
PS.....How much weight did your wheels take? Did you keep track of that?
I prefer the least weight possible to still get a good balance and will move the tire on a rim at times if one of them is asking for a lot more than the others. The rotor gives you something else in the mix to play with in an attempt to reduce the weights required.
As Fulton mentioned, you can always do a static balance to at least get an idea of where they are out of balance, but the average joe isn't going to have one of these available to do that with. If you do have access to one, it will help to reduce the number of wheel weights needed so that you can appropriately counter-index the heavier side.
Last edited by Stavesacre21; 08-26-2019 at 05:03 PM.