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Title: HR Discs
Post by: Glenn 'Stinky' Stankevicius on November 19, 2005, 09:49:40 AM

Can anyone confirm the minimum thickness for HR Discs?
According to the DBA catalogue, original minimum thickness is 9mm.
One disc on the ute is 9mm, does this mean I have to change or can I wait until they are under 9mm?

Title: Re: HR Discs
Post by: Dr_Terry on November 20, 2005, 05:20:03 AM

Hi Sticky.

The original thickness of a new HD/HR rotor is 3/8", which is between 9mm & 10 mm. I think the the 9mm minimum thickness is somebody's guess as there is/was no official minimum as there is for modern cars.

I think 9mm would be minimum safe & 8.5mm would be throw away.

Dr Terry

Title: Re: HR Discs
Post by: Glenn 'Stinky' Stankevicius on November 20, 2005, 06:01:54 AM

Thanks Doc.

Title: Re: HR Discs
Post by: Trevor_B on November 20, 2005, 09:15:37 AM

Hi Stinky,
The DBA Catalogue states 9.7mm original thickness & 9mm minimum - check here http://www.dba.com.au/DBAcat_012005.pdf

Regards,
Trevor_B

Title: Re: HR Discs
Post by: nicko on November 20, 2005, 12:23:30 PM

My HR Manual says .375inch(NOMINAL)
MAX RUN OUT .004 inch THEN REPLACE
dont know what that is in mm

Title: Re: HR Discs
Post by: Glenn 'Stinky' Stankevicius on November 20, 2005, 12:39:36 PM

Thanks Nicko, 0.375" (3/8") is 9.525mm (25.4mm to 1 inch).
That makes .004" 0.1mm which is pretty bloody small.
Isn't runout something to with straightness/tolerance, not wear?

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Technical Board => Modification Help => Topic started by: Glenn 'Stinky' Stankevicius on November 19, 2005, 09:49:40 AM