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Discussion Starter · #1 ·
It is so loud it will wake the dead. Will also keep wild animals within a 3-mile radius at bay. I am about to throw the bike over a cliff... :madman: :madmax: bud I paid too much for it to do that.:nono:

The rear is completely silent, surprisingly!


What I hear::
The front howls like a banshee as soon as the bike points downward! It is quiet under normal braking, but at moderate speeds (16 MPH or so) and under load (down a steep hill) the front brake is so loud I don't want to use it! It also creates a huge amount of vibration that I can feel through the bars and through my chest!! There are several distinct harmonics that I hear. I also hear a bit of noise from the spokes. And what's worse, when the vibration starts, I lose some braking power. It has done this for a year or so now.

Equipment:
Fox TALAS fork
XTR calipers
6" XT Rotors (not center-lock)
Shimano M06 metal pads
Mavic Crossmax SL wheelset

What I've done:
(1) replaced front pads, sanded rotors, cleaned rotors with isopropyl alcohol,

Still noisy

(2) Tightened all bolts, Tightened hub, tightened head set

Still noisy

(3) replaced pad and rotor with new (XT rotor, Shimano M06 pads)

Still noisy

(4) Replaced front pads with galfer pads. Wet-sanded rotors with 600 grit sand-paper until shiny new, sice I was changing pad compounds.

Still noisy

WTF? I give up. There's not much else I can replace. Maybe the wheel.

The fork was pushed a month or so ago it is an 04 fox talas, soit got new bushings and internals from an 05 model. No change in brake howl after getting it pushed.

Anything else I can do? The wheel is true and seems tight, but I have not had the spokes adjusted or anything. Could this come into play if the tension on some spokes was loose?

I am just going nuts about this!

Is it NOT the brakes that are at fault?

Thanks in advance....
 

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I already rode that
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1,632 Posts
Try getting the tabs on the fork faced? Or could be an issue with shims used.
Maybe one of the pistons isnt pushing out and the rotor is rubbing on the caliper itself?
Is the rotor centered in the caliper? You can tell easiest by removing the pads and looking at the caliper itself. When the pads are off it might also bea good time to clean the pistons too.

A year with it howling...you have more patience then I did when mine howled when I first got them but my howling went away after the first ride and even then it didnt last that long. Shuddering seems to happen sometime when first on a bike too. At least my other set of XTR calipers did that too on a fast downhill but only once.
 

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Meh.
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Resurface your pads by sanding in a figure 8 across course sandpaper.Resurface rotor with 600 grit and lots of water. Then douse both in alcohol. Torch the pads if you think they're contaminated.

Make sure that the pads are not grabbing the rotor arms.

You may need to have your disc tabs faced.
 

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My friend had same problem with his rear xtr. Shimano said there was a defect in the rotor design causing a vibration and the only cure is to replace it with an XT rotor. I think Shimano sent him one. Might be worth giving shimano a call.
 

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silly person
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If you do get your brake tabs faced, and reseat the caliper and feel that it is perfectly square and correct, then get some new brake pads too. The old pads will have worn to the old position and will most likely continue to howl. I managed to wear a set of XT 755 pads into a banana shape while attempting to eliminate a howling noise. In the end it was the pads causing it in an otherwise perfect setup.

If the pads have worn in a curved shape it will take you approximately forever to sand them back to flat. I estimated it would take me approximately 6 hours per pad to sand mine back to flat. (hey, they're a hard wearing part, what can I say)

A couple of other tips:
Make sure your rotor is firmly attached
Make sure there's no other loose points in the front wheel/hub

Heh, just reread your thread. Sounds like you've covered most of it already.


In your case I'd:
Get disc tabs faced
Replace pads

If that fails I'd

Look up price for new brakes

Does the front brake feel at all squishy when you just squeeze it, like there's a lack of defined contact point?
 

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EJ, you may have a good point, maybe the XTR lockring style rotors have some float that allows it to wobble slightly? I am using the XT bolt-on rotors and I don't have any noise issues.
 

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Discussion Starter · #10 ·
Hah!!! Fixed It...

After swapping to the galfer pads last Friday, I just did some parking lot braking and heard the same howling noise and thought I still had the problem.

Not so!

Just rode Cannel trail and plunge this weekend with Maddog and I did not hear a peep out of the brakes. There's enough serious downhill there to get them good and hot. No fade either, which surprised me as I am generous with the brakes on the steep stuff. I was ready to swap to a 7" or 8" front rotor too (to help keep the heat down since I thought that was part of the problem). I now realize that a 6" front rotor is enough for me!! yay! no more throwing money away on brake stuff.

At this point I am ready to say that shimano brake pads suck for serious down hill riding. I mean, I had previously swapped to a new XT rotor and new shimano pads and then went and rode skeggs point and the squealed as loud as ever.

So there you have it. I am still on shimano XTR calipers and shimano 6" XT (non center-lock) discs, but the setup is so much better with the Galfer pads. They were cheaper than shimano's too by about 40%!

Galfer pads rule! :D

Shimano's M06 metallics suck! :madman:

End of story! :cool:
 

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Excellent news. Which model of Galfer pads did you get? metal, resin? Or is there only one?

FSRguy said:
After swapping to the galfer pads last Friday, I just did some parking lot braking and heard the same howling noise and thought I still had the problem.

Not so!

Just rode Cannel trail and plunge this weekend with Maddog and I did not hear a peep out of the brakes. There's enough serious downhill there to get them good and hot. No fade either, which surprised me as I am generous with the brakes on the steep stuff. I was ready to swap to a 7" or 8" front rotor too (to help keep the heat down since I thought that was part of the problem). I now realize that a 6" front rotor is enough for me!! yay! no more throwing money away on brake stuff.

At this point I am ready to say that shimano brake pads suck for serious down hill riding. I mean, I had previously swapped to a new XT rotor and new shimano pads and then went and rode skeggs point and the squealed as loud as ever.

So there you have it. I am still on shimano XTR calipers and shimano 6" XT (non center-lock) discs, but the setup is so much better with the Galfer pads. They were cheaper than shimano's too by about 40%!

Galfer pads rule! :D

Shimano's M06 metallics suck! :madman:

End of story! :cool:
 
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