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      11-24-2012, 02:19 PM   #1
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Cleaning cross-drilled rotors?

I couldn't find this in a search, and it's an odd question: the cross-drilled openings in my rotors are full of brake pad dust - some are completely closed, others are half-full. Is this normal?

I understand the purpose of cross-drilling, and this doesn't seem optimal? I cleaned them out, just wondering if a) this is normal and b) requires maintenance?

Thanks!
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      11-24-2012, 03:23 PM   #2
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Happened on my OEM ones constantly. I believe it's normal. I just used a hose with pressure to clean them out each time.
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      11-24-2012, 05:25 PM   #3
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You can also use screwdriver or something similar.
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      11-24-2012, 08:48 PM   #4
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Would compressed air do the trick?
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      11-24-2012, 08:56 PM   #5
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4mm allen t-handle
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      11-24-2012, 09:57 PM   #6
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What bad advice being given here..do not "gauge" at the holes with any tools. Try washing and spraying with a hose
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      11-24-2012, 10:53 PM   #7
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Quote:
Originally Posted by Amri215
What bad advice being given here..do not "gauge" at the holes with any tools. Try washing and spraying with a hose
What he said.

Just a hose or compressed air works. The dust doesn't fuse itself in. It's relatively easy to remove and comes off with gentle force. If you wash your car yourself, just aim the water on each hole directly and the dust breaks free and your done. Proceed with the rest of the car.
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      11-25-2012, 12:55 AM   #8
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Bueno - partially cleaned them out with a bamboo skewer (bbq), will wash them out fully while washing tomorrow.

Cheers
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      11-25-2012, 08:01 PM   #9
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Quote:
Originally Posted by Amri215 View Post
What bad advice being given here..do not "gauge" at the holes with any tools. Try washing and spraying with a hose
. i think you mean "gouge" but you aren't going to hurt a steel rotor that sees 1200+ degrees and thousands of lb-ft of torque sticking something in the holes to clear them. You know the inboard face of the rotor has holes in it too, right? How well does spraying water clean the inboard side? What happens when a clod of wet brake dust gets stuck in a vane? It turns to cement as soon as it dries.
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      11-25-2012, 09:04 PM   #10
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Quote:
Originally Posted by Richbot View Post
. i think you mean "gouge" but you aren't going to hurt a steel rotor that sees 1200+ degrees and thousands of lb-ft of torque sticking something in the holes to clear them. You know the inboard face of the rotor has holes in it too, right? How well does spraying water clean the inboard side? What happens when a clod of wet brake dust gets stuck in a vane? It turns to cement as soon as it dries.
Yes I meant gouge..and yes you can damage the OEM galvanized coating on the surface of the rotor. It has nothing to do with the rotor's thermal capacity

If you have plugged up brake rotor holes you are simply not washing the car enough..as others have said simple hose will take care of it..nothing turns to cement.

On the inboard side it wouldnt matter as you cant see it..we are talking only aesthetics here.
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      11-25-2012, 10:02 PM   #11
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Galvanized!? No. The floating rotor is bare iron. Look at photos of oxidation inside the holes and inner radius on used rotors for proof, or just know what a zinc coated part looks like and realize they aren't coated...
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      11-26-2012, 08:37 AM   #12
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I used q tips with Brakleen on my Cayman, I don't think it does anything other than improves looks though. They would get full of stuff again in like 1 track day.
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      11-26-2012, 04:28 PM   #13
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It's probably about 30g of unsprung rotating weight! -0.5 seconds! +50hp!
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      11-27-2012, 11:28 AM   #14
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Quote:
Originally Posted by Richbot
It's probably about 30g of unsprung rotating weight! -0.5 seconds! +50hp!
LOL
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