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Disque Break Pads: Ware them down to the boan?

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Disque Break Pads: Ware them down to the boan?

Old 03-16-22, 11:50 AM
  #26  
Polaris OBark
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Originally Posted by surak View Post
Not based off any casual search I've done, and that's also forgetting that there's a 3x price difference between pads vs rotors.
On Amazon, L03A pads are $80, which is more than I have ever paid for an Ultegra rotor.

(I have a backup stash of rotors, too. I wrongly wrote J03A, which are currently available at a semi-reasonable price.)
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Old 03-16-22, 11:57 AM
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Here is the problem. I am taking these off while they still technically have a bit of life left in them, and it seems kind of wasteful in a time of scarcity.


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Old 03-17-22, 02:48 PM
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whatsa boan
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Old 03-17-22, 03:40 PM
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Originally Posted by BikeLite View Post
whatsa boan
It's Bad 2 Da Boan.
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Old 03-17-22, 03:54 PM
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Originally Posted by Polaris OBark View Post
Here is the problem. I am taking these off while they still technically have a bit of life left in them, and it seems kind of wasteful in a time of scarcity.


So how are you measuring those to determine they are worn? It's only the pad thickness that you go by. With calipers, zero them out on the base the pads are mounted to, then measure the entire thing which will give you the pad thickness relative to where you zeroed the calipers.


https://si.shimano.com/pdfs/dm/DM-R8050-01-ENG.pdf

What do you do to get that many worn out pads? That's like 24 years of cycling for me! <grin>
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Old 03-17-22, 04:18 PM
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Originally Posted by Iride01 View Post
What do you do to get that many worn out pads?
Long downhills.

The ones that can take you well over 30 mph.

And folks that don't want broken bones.
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Old 03-17-22, 06:17 PM
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Originally Posted by Iride01 View Post
So how are you measuring those to determine they are worn? It's only the pad thickness that you go by. With calipers, zero them out on the base the pads are mounted to, then measure the entire thing which will give you the pad thickness relative to where you zeroed the calipers.


https://si.shimano.com/pdfs/dm/DM-R8050-01-ENG.pdf

What do you do to get that many worn out pads? That's like 24 years of cycling for me! <grin>
About 90% are mine. The sick thing is I've gone through many more. I do about 3000 ft of steep downhill (up to 22% grade) and 3000 ft of uphill on my usual ride/commute (just did so today, about 25 miles), on narrow winding roads in the redwoods, so I brake a lot. Couple that with sub-clinical paranoia, and I have personally depleted the word's supply of J03A and its predecessors.


I am measuring the pad + backing and subtracting from that sum the backing only, using digital calipers (the functional equivalent of re-zeroing, but mine don't do that). I've been changing them at about 0.9mm net thickness, which is what the instructions I read said to do. They must have revised the instructions, which would make sense, because the bone-shaped wear pattern is visible at 0.5mm.

The good thing about that collection/hoard is I can go back and put them in and wear down about 0.3 or 0.4 mm more in many instances. (I would put them in the back so as not to die.)

That pretty much answers my question, if they have revised the advisory to change when worn to a net thickness of 0.5mm.

Last edited by Polaris OBark; 03-17-22 at 06:28 PM.
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Old 03-18-22, 02:27 AM
  #33  
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Originally Posted by soyabean View Post
It's Bad 2 Da Boan.
i shoulda noan that
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Old 03-18-22, 08:05 AM
  #34  
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Polaris OBark

Just notice that I was only showing that as a reference for how to measure. And that my example is from the DM for the Ultegra R8050 series which covers my BR-R8070 brakes. So find the manual for your brakes to get the minimum recommended pad thickness.

https://si.shimano.com/

If you go through that many pads, then maybe you'd be better off wearing them down to nothing and just accepting that you might have to replace the entire brake every so often. Or find someone that can give you a really good deal if you buy brake pads by the gross. <grin>
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