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Author Topic: Warped my rotors?  (Read 955 times)

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Offline exponent

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Warped my rotors?
« on: January 14, 2021, 09:11:42 am »
Pretty sure I warped my rotors on my cb550. My guess is either it happened when I was drilling them, or when I leaned the wheel with rotors against my workbench. I can't get these true again right? I have not balanced or trued my wheel yet but the amount of side to side is way off.
https://youtube.com/shorts/HsUyq7oT0zs
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Offline calj737

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Re: Warped my rotors?
« Reply #1 on: January 14, 2021, 09:21:46 am »
That video clip is pretty inconclusive. There could be many factors contributing to the runout. If you are determined to know for certain, unmount the rotor, clamp it to a known "axle" and use an indicator to measure the runout. But also be certain to measure the bolt face area as the rotor surface may no longer be parallel to the mount surface (on the rotor or the hub).
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Offline 754

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Re: Warped my rotors?
« Reply #2 on: January 14, 2021, 01:03:00 pm »
 I can see runout on the one.  Get it off and check mounting surface... these are pretty hard to bend. .
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Offline exponent

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Re: Warped my rotors?
« Reply #3 on: January 14, 2021, 01:43:41 pm »
Quote from: 754 on January 14, 2021, 01:03:00 pm
I can see runout on the one.  Get it off and check mounting surface... these are pretty hard to bend. .

Would wheel trueness affect the runout of the rotor?

Also when the rotor is removed and I lay it flat side down on another flat surface I can tip the rotor. Like when pressing down around the edge I can rock it back and forth in a certain place.
« Last Edit: January 14, 2021, 01:48:34 pm by exponent »
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Offline bryanj

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Re: Warped my rotors?
« Reply #4 on: January 14, 2021, 02:07:54 pm »
If you have warped one of those you are the first in 40 yrs but i suppose drilling could weaken it
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Offline seanbarney41

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Re: Warped my rotors?
« Reply #5 on: January 14, 2021, 02:19:42 pm »
Quote from: bryanj on January 14, 2021, 02:07:54 pm
If you have warped one of those you are the first in 40 yrs but i suppose drilling could weaken it
Ha ha, yeah, I was talking on the phone to my guy who drills, thins and surfaces them on the phone before I sent him some to do his magic.  And he said he has seen one out of literally hundreds that had been made unserviceable.  He said it must have been involved in a very severe crash.
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Offline jonda500

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Re: Warped my rotors?
« Reply #6 on: January 14, 2021, 03:51:41 pm »
wheel trueness can't affect rotor trueness.
the left one looks fine, take the RH one back off and work out why it's not mounting totally flat. post a pic of the bolt hole area inner side - it should be flat!
John
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Offline exponent

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Re: Warped my rotors?
« Reply #7 on: January 14, 2021, 04:23:35 pm »
Gonna sand them to smooth out the holes I drilled and see if that does anything, hopefully I'm just paranoid and once everything comes together it'll brake smoothly but...
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Offline 754

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Re: Warped my rotors?
« Reply #8 on: January 14, 2021, 07:38:03 pm »
It is not the drill holes in the video, the disc appear to be mounted with something between it and the wheel..
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My next bike will be a ..ANFOB.....

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Offline scottly

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Re: Warped my rotors?
« Reply #9 on: January 14, 2021, 09:30:28 pm »
Is the center of the rotor directly against the hub? Are you trying to use the speedometer drive?
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Offline exponent

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Re: Warped my rotors?
« Reply #10 on: January 14, 2021, 09:53:49 pm »
Quote from: 754 on January 14, 2021, 07:38:03 pm
It is not the drill holes in the video, the disc appear to be mounted with something between it and the wheel..

I'm using spacers as I messed up my speedo drive, I wanted to keep it but the holes I drilled were off and I didn't get around to fixing it. It should be the rotor against the hub but I could clean and brush both surfaces
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Offline scottly

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Re: Warped my rotors?
« Reply #11 on: January 14, 2021, 10:07:10 pm »
There are spacers the correct length to replace the speedo drive gearbox. The gearbox is driven from a plate that sits against the surface where the rotor carrier now sits. Just what do you mean by "messed up the speedo drive"? Please post more pics. 
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Offline exponent

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Re: Warped my rotors?
« Reply #12 on: January 15, 2021, 06:32:02 am »
Speedo drive holes were misaligned
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