[ZR1] 2012/13 rotors vs pre 2012
11-01-2012, 06:47 PM
#1
Safety Car
Thread Starter
2012/13 rotors vs pre 2012
This, will answer that question that some of us were wondering (I've posted it in my shimmy thread too):
2013 Z06/Z07, see the added screwed on weight to balance the rotor (both side have them).
Problem is: my dealer does not know how or where to get those weights from nor has any instructions pointing to balancing using those screw on weights....so if anyone knows, please post or PM me.
2013 Z06/Z07, see the added screwed on weight to balance the rotor (both side have them).
Problem is: my dealer does not know how or where to get those weights from nor has any instructions pointing to balancing using those screw on weights....so if anyone knows, please post or PM me.
11-01-2012, 06:58 PM
#2
Drifting
My new rotors came with the weight already attached, balanced at the factory.
BTW, for those wondering, the old rotors can't easily be balanced like that as the new rotors are drilled and tapped with screw holes all around the hub surface for that weight you see. Meaning, there are holes all around that hub just where that weight is attached, all but the one you see there with the weight are unused.
The old rotors are not drilled like that to accept a weight.
BTW, for those wondering, the old rotors can't easily be balanced like that as the new rotors are drilled and tapped with screw holes all around the hub surface for that weight you see. Meaning, there are holes all around that hub just where that weight is attached, all but the one you see there with the weight are unused.
The old rotors are not drilled like that to accept a weight.
Last edited by jft69z; 11-01-2012 at 07:31 PM.
11-02-2012, 02:09 PM
#3
Le Mans Master
I can't hardly believe what I'm seeing!!! After everything I have been thru, up and down the road.......back and forth to the specialty tire shop for the balance and RFB and then back again and all the time the fix was right on my 2012 rotors? I called my service dept and they had never heard about it and could not find any type of bulletin regarding this. I went out and looked at my rotors and sure enough I have those drilled and tapped holes. This is obviously something our "Chevy Cust Service" was not told about as well. 
Thanks for the post
Thanks for the post
Last edited by ufaj26; 11-02-2012 at 02:14 PM.
11-02-2012, 07:37 PM
#6
Drifting
The weight on my new rotor was a little bigger than the one in the previous picture from mirage2991. It's near the bottom. Guessing it's only available from Brembo & if you have the new rotors drilled to accept the weights, they already balanced it at the factory.
With use down the road though, who knows if the balance will change. Time will tell. Then we'll just have to get creative...
With use down the road though, who knows if the balance will change. Time will tell. Then we'll just have to get creative...
Last edited by jft69z; 11-02-2012 at 07:40 PM.
11-02-2012, 07:38 PM
#7
Race Director
Produce advanced composite, light weight rotor and don't put effort into properly balancing them while machining. Then, add weight to advanced composite, light weight rotor and call it good.
Nice fix
Shame on GM and Brembo.
Nice fix
Shame on GM and Brembo.
11-02-2012, 08:18 PM
#8
Safety Car
Thread Starter
The weight on my new rotor was a little bigger than the one in the previous picture from mirage2991. It's near the bottom. Guessing it's only available from Brembo & if you have the new rotors drilled to accept the weights, they already balanced it at the factory.
With use down the road though, who knows if the balance will change. Time will tell. Then we'll just have to get creative...
With use down the road though, who knows if the balance will change. Time will tell. Then we'll just have to get creative...
11-02-2012, 08:52 PM
#9
Drifting
How much are they off? One of my new rotors doesn't have a weight & the car rides smooth. At the time I asked if they were going to check the new ones & they said no, just put them on & see what happens. I guess I got lucky.
Did you put them on & test drive it, or just reject the new rotors outright after testing the balance?
Did you put them on & test drive it, or just reject the new rotors outright after testing the balance?
11-02-2012, 11:05 PM
#10
Safety Car
Thread Starter
How much are they off? One of my new rotors doesn't have a weight & the car rides smooth. At the time I asked if they were going to check the new ones & they said no, just put them on & see what happens. I guess I got lucky.
Did you put them on & test drive it, or just reject the new rotors outright after testing the balance?
Did you put them on & test drive it, or just reject the new rotors outright after testing the balance?
Tech called me earlier and said to test the active handling, as he said he had heard of a vette that was doing the vibration and was related to the active handling/ABS being bad...I will give that a shot but won't hold my breath either...
Last edited by mirage2991; 11-02-2012 at 11:12 PM.
11-06-2012, 09:45 PM
#12
Why can't the rotors be balanced by removing material at the periphery of the rotor?
11-07-2012, 08:03 AM
#14
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11-07-2012, 11:17 AM
#15
Racer
Question.
I know my rotors are off 0.5 and 0.25 oz off balanced and are marked at the spot. (this was done to Aston Martin Bulletin instructions with A hunter Machine)
My rotors have been tapped so I could potentially make my own weights.
Can I use the same weight value to attach on the rotor? Should it be significantly larger since the weight is attached at a much shorter radius?
I know my rotors are off 0.5 and 0.25 oz off balanced and are marked at the spot. (this was done to Aston Martin Bulletin instructions with A hunter Machine)
My rotors have been tapped so I could potentially make my own weights.
Can I use the same weight value to attach on the rotor? Should it be significantly larger since the weight is attached at a much shorter radius?
11-08-2012, 06:50 AM
#17
Race Director
Looks like GM/Brembo have finally recognized the problem without publicly saying so. Took them long enough to do so. No problems with my 2011. Going to look for those screw holes tonight but not likely my mid year will have them.
No problems with my 2011. Going to look for those screw holes tonight but not likely my mid year will have them.
11-08-2012, 08:11 AM
#18
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Thanks for all the updates JB! I think when I have mine done in the Spring they should do it at Milford so the Engineers are right there and I can test it on the track 
11-11-2012, 01:05 AM
#19
Team Owner
Question.
I know my rotors are off 0.5 and 0.25 oz off balanced and are marked at the spot. (this was done to Aston Martin Bulletin instructions with A hunter Machine)
My rotors have been tapped so I could potentially make my own weights.
Can I use the same weight value to attach on the rotor? Should it be significantly larger since the weight is attached at a much shorter radius?
I know my rotors are off 0.5 and 0.25 oz off balanced and are marked at the spot. (this was done to Aston Martin Bulletin instructions with A hunter Machine)
My rotors have been tapped so I could potentially make my own weights.
Can I use the same weight value to attach on the rotor? Should it be significantly larger since the weight is attached at a much shorter radius?
Because the factory supplied them to us out of balance?
Why not use a stick-on wheel weight, otherwise you need to allow for the weight of the fastner.
