Avid XX brakes = sad face emoticon
So far after 3 races and a month of training, my swank Avid Elixir 2011 XX brakes are a massive disappointment. They absolutely pale in comparison to the XT brakes .I run on my Vassago, which has made me appreciate my XT like never before.
1. Someone please tell me how to stop the chirping/squeak from hell that I hear every time I use my brakes. Whether feathering or slamming on the brakes, there is a terrible metal on metal screech. I am running the correct brake pads. I have tried rubbing alcohol on the rotors and I have scuffed up the rotors with sand paper. Doesn't seem to work. I don't exactly ride the brakes and now I am using them even less.
2. On my second ride, I was 40 minutes in and had just finished descending for about a minute when I got off and noticed the rear rotor had heated up so much it was entirely scorched black. I wasn't exactly DHilling, but spinning fire roads. I have changed out the pads and while there is no more scorching, the brakes still squeak.
Obviously these brakes are pricey and I would like to continue to use them. Other than dumping the brakes and eating the cost, any thoughts on how I might put an end to the noisy rotors?
interesting you say that you rarely ride your brakes. the dark color left on your rear rotor means you either warped the rotor or there is contamination in the system. you may be using a too small a rotor size for your type of riding or your weight.
the noise is persistent due to improper break in. i have seen avid brakes honk and screech when pads are not properly bedded to the rotors. biggest factor to howl and honks are pad or rotor contamination. check to see if you have any leaks around your calipers or pistons as even a small amount of brake fluid will ruin a set of pads/rotors. you should try scorching your pads over fire to burn off any contaminants and scuff your rotors to remove the burned on darkness.
i have a set of '12 elixir 9 brakes that have been noise and trouble free for over 3 months. they only make noise when wet and they work flawlessly with great power and modulation. I might go so far as to say they perform better than shimano's new xt that ive demoed on a SC Highball.
Thanks. The scorching occurred on the first ride and at the rear rotor. I have 160mm on the rear because the 140mm wouldn't fit (Fisher Superfly SS, first year). I am purely an xc type. The warped rotor happened very quickly, just after I tuned off a fireroad and down a steep descent that probably takes a minute max to clean. I ride this all the time and never once have my previous brakes scorched like this, neither the XT or the old Avid's I had on there. I should add that the scorched coloring faded as soon as the rotors cooled. I should also mention that this happened only one time.
I will look for contaminants and try to scorch the pads as you suggest. I have ordered new Organics as well and will make sure to bed them correctly. I even ordered that Squeal- out stuff as a last resort.
This morning I rubbed some alcohol on the rotors before my ride. For a few short, but glorious minutes the XX brakes were as quiet as can be and I absolutely loved them in those fleeting moments. Unfortunately, it didn't last. The Turkey Gobble was absent, but the screeching ever present.
Try sanding your pads back to virgin look on a large whetstone (ie remove the shine). This should help to make them more level/flat You'll need to bed the pads back into the rotor again.
If this is unsuccessful then you may have put some irreversible slant to the pad that prevents it from ever hitting the rotor in a fully flush manner.
When you bed pads in too, I've always been told that short applications but many of them is the way to go. If you just massively accelerate then jam the brakes on to stationary, then glazed pads and an overheated rotor will be the result.
Oh, and if you expect that a WW race brake will ever be as good as a much heavier XT then you may have had some unreal expectations. All superlight brakes suffer from lower braking power.....apart from Formula R1/the One of course
Rimmer - "There's an old human saying - if you talk garbage, expect pain"
The turkey gobble is a well-known issue with Avid brakes.
You can spend some time reading about it here