Scraping from front disc brake
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Joined: Jul 2019
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From: TX
What year is the bike and how many miles on it? More accurately, how many miles are on the pads? See if you can get a photo of the out board brake pad where it touches the disc.
As said, it isn't uncommon for the pads to very lightly contact the disk even when no hydraulic pressure is being applied. I will say, though, that I don't hear anything like that when roll my '18 Low Rider around in the garage.
As said, it isn't uncommon for the pads to very lightly contact the disk even when no hydraulic pressure is being applied. I will say, though, that I don't hear anything like that when roll my '18 Low Rider around in the garage.
I'll try to get a picture once I get back home.
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From: Pennsylvania
Did you wash it and put it away? Sometimes the rotors will get some rust (corrosion) on them if you wash the bike and do not ride it for a mile or so before putting it away. Then you will hear the scraping sound you are talking about. Take the bike out and ride it a couple of miles and put the front & rear brakes on a couple of times. The see if you still hear the noise.
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From: TX
Did you wash it and put it away? Sometimes the rotors will get some rust (corrosion) on them if you wash the bike and do not ride it for a mile or so before putting it away. Then you will hear the scraping sound you are talking about. Take the bike out and ride it a couple of miles and put the front & rear brakes on a couple of times. The see if you still hear the noise.
Most of the time, if it gets very dirty, I use a no-rinse solution to get rid of the dirt/dust. I've probably washed it (traditional wash with suds/water) twice. Definitely not a garage queen.I rode about 150 miles yesterday and after that, as I parked it in the garage, decided to turn it around facing out for a ride today), and that's when I noticed this sound. Usually, I use a dolly to turn it around, so I don't hear it.
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From: TX
Tourer
Joined: Jun 2020
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From: Fairfax, Va
A 2019 with only 2K miles clearly hasn't worn out the pads, and your pics confirm that.
The pads sit far to close to the discs to actually get anything lodged between the two, but as mentioned above sometimes a small stone can get stuck on the top, short edge of the pad, more likely when the there is a lip between the pad material and the metal backing plate. But given the design of the front caliper on these bikes that's very unlikely I think.
If the brakes feel fine, and if you don't see any bad grooves in the disc itself, my guess it's just a spot in one of the pads. They aren't of the highest quality. It'll probably go away after a bit of riding.
The pads sit far to close to the discs to actually get anything lodged between the two, but as mentioned above sometimes a small stone can get stuck on the top, short edge of the pad, more likely when the there is a lip between the pad material and the metal backing plate. But given the design of the front caliper on these bikes that's very unlikely I think.
If the brakes feel fine, and if you don't see any bad grooves in the disc itself, my guess it's just a spot in one of the pads. They aren't of the highest quality. It'll probably go away after a bit of riding.
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From: TX
A 2019 with only 2K miles clearly hasn't worn out the pads, and your pics confirm that.
The pads sit far to close to the discs to actually get anything lodged between the two, but as mentioned above sometimes a small stone can get stuck on the top, short edge of the pad, more likely when the there is a lip between the pad material and the metal backing plate. But given the design of the front caliper on these bikes that's very unlikely I think.
If the brakes feel fine, and if you don't see any bad grooves in the disc itself, my guess it's just a spot in one of the pads. They aren't of the highest quality. It'll probably go away after a bit of riding.
The pads sit far to close to the discs to actually get anything lodged between the two, but as mentioned above sometimes a small stone can get stuck on the top, short edge of the pad, more likely when the there is a lip between the pad material and the metal backing plate. But given the design of the front caliper on these bikes that's very unlikely I think.
If the brakes feel fine, and if you don't see any bad grooves in the disc itself, my guess it's just a spot in one of the pads. They aren't of the highest quality. It'll probably go away after a bit of riding.
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From: Sandy Eggo's North County
Yep, pads do drag across the rotor's swept surfaces always.
The design rational is it keeps the rotor "clean" for immediate braking in wet/icy/cold/hot/dusty environments that any bike could be subjected to.
EDIT~ OP, it's good that you noticed this "change" in sound. We, as motorcyclists, use every sense we have to notice a "change" in our vehicles. In your case, it is simply the pads finally fully "bedding-in" for their service life.
However, sometimes, it can be a safety issue, so inspection is warranted. This, you just did. Good on you!
Sometimes corrective action is needed, sometimes it is "normal." (Read: "They all do that...")
Go ride yer bike, Grasshopper!
But, always look/listen/smell for "changes" in the future.
The design rational is it keeps the rotor "clean" for immediate braking in wet/icy/cold/hot/dusty environments that any bike could be subjected to.
EDIT~ OP, it's good that you noticed this "change" in sound. We, as motorcyclists, use every sense we have to notice a "change" in our vehicles. In your case, it is simply the pads finally fully "bedding-in" for their service life.
However, sometimes, it can be a safety issue, so inspection is warranted. This, you just did. Good on you!
Sometimes corrective action is needed, sometimes it is "normal." (Read: "They all do that...")
Go ride yer bike, Grasshopper!
But, always look/listen/smell for "changes" in the future.
Last edited by NORTY FLATZ; Jul 6, 2020 at 10:47 AM.
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From: Farmington ,MS
The only thing that backs the pads up is the run-out the rotor has..which means you will always have some contact...
How much noise you have will depend on what kind of pads you have...some are noisier than others...some are very noisy when cold but quiet down when they heat up...
How much noise you have will depend on what kind of pads you have...some are noisier than others...some are very noisy when cold but quiet down when they heat up...
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Thread Starter
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Joined: Jul 2019
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From: TX
The only thing that backs the pads up is the run-out the rotor has..which means you will always have some contact...
How much noise you have will depend on what kind of pads you have...some are noisier than others...some are very noisy when cold but quiet down when they heat up...
How much noise you have will depend on what kind of pads you have...some are noisier than others...some are very noisy when cold but quiet down when they heat up...
Brake caliper piston seals are designed to stretch a little before they slide. That way they pull the piston back from the pads just a tiny bit when hydraulic pressure is removed. The pads are loose with a metal spring that pushes in the radial direction and keeps them from rattling around. The pads are not pulled back by the pistons so they may rub a little on the rotor but the drag torque and noise should be minimal.