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Discussion Starter · #1 ·
Is it common for disc brake rotors to make a high pitched metallic sound when you are turning at speed? I am guessing it's the rotor hitting the pads.
I do have my brake pads adjusted really close against the rotors. In fact, they're as far as it will go on the Elixir 9s adjustment on the lever.
The rotors are fully tightened to spec. I checked when putting it together and also double checked it after it was making that sound.
It will only make the sound when turning the bike. I cannot reproduce the sound unless I am on it, going over about 10 mph and turning.
 

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My Elixir 3s make this horrible intermittent squeal when I'm riding. I've adjusted the calipers, many, many times, and tried to true the rotors as best as I can. The most frustrating thing is that they don't make any noise at all when I'm off the bike and spinning the wheels, only when I'm riding the bike, and not all the time.

After a lot of frustration, I began to suspect that it might not be the rotors that are the problem at all. To confirm my suspicion, I carefully put a thin film of grease on brake pad spreader where it contacts the two brake pads and voila! I had my first quiet, peaceful ride for a long, long time. I've never been out to ride again since then so I'm not yet a hundred percent sure but I suspect that since the pads do move around a little bit as you are riding, they will somehow rub against the rotors; I think that this makes the brake pad spreaders in the Elixirs resonate and squeal.

Bear in mind that I still have to really prove that this is the problem with my brakes but it's something you might want to look into with yours.
 

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I've got the exact same situation as OP. It happens when I turn going fast but I also hear it when I let off the brake after a hard brake. It took me a while to figure out what it was until, like you said, I flicked the rotor with my finger nail and it made the exact noise.
 

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Is it common for disc brake rotors to make a high pitched metallic sound when you are turning at speed? I am guessing it's the rotor hitting the pads.
I do have my brake pads adjusted really close against the rotors. In fact, they're as far as it will go on the Elixir 9s adjustment on the lever.
The rotors are fully tightened to spec. I checked when putting it together and also double checked it after it was making that sound.
It will only make the sound when turning the bike. I cannot reproduce the sound unless I am on it, going over about 10 mph and turning.
Not uncommon at all. As long as everything is tight, wheel bearings, mounting bolts, etc. Then what you are experiencing is frame and/or fork flex. All frames and forks flex under stress, some more, some less. If they didn't they'd break. When you are cornering hard you are simply flexing the frame or fork (or both) enough for the brake pads to make light contact with the rotor that will usually produce an intermittent clang or pinging sound.

Nothing to worry about, and certainly not uncommon. It just means you ride hard. :thumbsup:

Good Dirt
 

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I sometimes get this same sound as the OP. Its more of a "Zing!" as the rotors brushes a pad occasionally while turning hard. I have also been told it may be more common on the larger size rotors as they have more room to "flex". Nothing to be too worried about.
 

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Or maybe your front pads and rotor are oiled or greassy.
Try to clean it up with cocacola
are you serious? how about something that won't leave a sticky residue?

If the fork is flexing, you're more likely to have problems here. I occasionally hear this on my Fox Float RL with regular QR. A 9mm RWS thru will stiffen things up more. This is one reason why 15mm thru axles are becoming more common for AM/XC bikes and why 20mm is common for even burlier bikes.
 

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Discussion Starter · #13 ·
Try to clean it up with cocacola
Soda? No way, I use grape kool-aid for tough cleaning jobs :p Seriously though, the cocacola trick is supposed to degrease engines. I remember reading the mechanics that work on the Coke trucks use it. It sounds funny but maybe it's true. Most likely it's just Pepsi doing some defensive marketing warfare.

I think it's the flexing fork thing as that makes the most sense. Tonight I will loosen back on the brake pads from the rotor with that adjustment knob and see if it goes away. It doesn't bother me really, I just didn't know if it was doing harm.
Now that I know it's harmless, even if it goes away, I would probably still adjust the pads back to being close again as I like that instant grip I get from the pads being so tight to the rotors.
 

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I always clean the rotors with alcohol (non-malted barley type); wear gloves or do your best to not touch the outer braking edge of the rotors.

I'd also lean towards the rotor being out of true; that certainly has happened to me.
 
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