Brake Disc Thickness

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tasroadster
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Brake Disc Thickness

Postby tasroadster » Sun Apr 09, 2006 5:31 pm

What's the min. thickness for 1990 NA front Disc's ?

What's the thickness of the NA8 front disc's..... are they the same as the NA6 ? They are 255 mm right ?

Any help greatly appreciated.

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Inf3ct0R
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Postby Inf3ct0R » Sun Apr 09, 2006 8:35 pm

na8/nb8a are 255mm, na6 are smaller.
min thickness for the 255mm should be 20mm... i think.

the figure should be casted onto the disc, around the hub area on the inner side

tasroadster
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Postby tasroadster » Sun Apr 09, 2006 8:39 pm

So I can use 255mm disc's which are 21 mm thick ?

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Inf3ct0R
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Postby Inf3ct0R » Sun Apr 09, 2006 8:41 pm

yup, I had mine machined down to 19mm

tasroadster
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Postby tasroadster » Sun Apr 09, 2006 8:50 pm

So.... what happens if I just run then at 21 mm thick ?

Is there any problems with that ?

Thanks

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Inf3ct0R
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Postby Inf3ct0R » Sun Apr 09, 2006 9:12 pm

nope, once you hit 20mm, i'd be looking at buying new rotors, they are at a higher risk of cracking/overheating

tasroadster
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Postby tasroadster » Sun Apr 09, 2006 9:19 pm

So leave them as is ?

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Inf3ct0R
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Postby Inf3ct0R » Mon Apr 10, 2006 1:05 am

depends on how hard your driving and what pads your running, but once you get them machined and hit 20mm then replace them..

tasroadster
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Postby tasroadster » Mon Apr 10, 2006 1:14 am

machine them to what thickness?

20.5 mm ?

Thanks

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Craig
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Postby Craig » Mon Apr 10, 2006 1:20 am

Here's some disk info to assist.

Image
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Inf3ct0R
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Postby Inf3ct0R » Mon Apr 10, 2006 1:20 am

the machinist should be machining to whatever thickness is needed for a smooth consistent surface.

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Postby Inf3ct0R » Mon Apr 10, 2006 1:24 am

well, there ya go min thickness 18mm

must have my stock disc @ 17mm or something then LOL

btw, if your disc are 21mm, then they sound brand new!!


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