The frame resonance theory is not suspect, and in many cases the cause of the shudder that you get from brakes.
Take the Fluid LTs from 2008 for example. Norco acknowledged the issue, and warrantied the seatstay assemblies. Correctly aligning the caliper is important, but if that has been done then it's time to look at the bearings, bushing and eventually the frame itself. Changing pad compound is a band aid solution.
Thanks for all the replies! I will continue to play with the alignment and hope I can find the sweet spot.
I've tried my usual method of loosen the calipers, squeeze the brake and re-tighten the bolts a few times with no success. This has worked for my other brakes but obviously its not accurate enough for the elixirs. I'll try and get them centered by eye and let you know how I go.
throw some wd-40 on there
Damn, the answer was so obvious I should have thought of it myself! I better give the front brake a spray while I'm at it.
I had the same problem with my elixir Rs on my Blur LT2. I tried everything I could think of (checking pivots, realigning caliper ect.) and nothing working. I researched the problem and found a posting on this forum about the new rotors without vents. I went into the shop in which I bought the bike and the head tech had not heard of the new rotors. However he did try to realign them (didn't work) and offered to replace the stock pads with organic (they had to order them in). He said ride around and sometimes the problem will just disappear. I didn't really believe him, however after a few more rides the vibration and noise stopped. They still howl when the get wet but I can live with that. I still don't know what the problem was…
organics aren't as powerful and they wear out faster and they fade easy.
Tried couple in the past, never really liked organic pads much, didn't feel the "bite" as much
Guys should check out the video on the Hope site for alignment of the caliper. Hope insist that the simple method of loosening the caliper bolts, squeezing the brake lever and tightening those caliper bolts while holding the brake on is not good enough. Hope claim using your eyeballs to get the rotor absolutely centered between the pads and straight is the best way. That way you don't get the leading edge of one pad flicking along the vent holes in the rotor and the brake pistons will be coming out straight instead of a little cockeyed so power and efficiency is maximized. I don't know if it that critical but alignment jobs are free so why not do it?
this is how mine were set up. no squeaks at all. i know a few buddies set them up the same way… NO PROBLEMS!
the "blaming it on the frame" story is funny. typical whistler…
The frame resonance theory is not suspect, and in many cases the cause of the shudder that you get from brakes.
Take the Fluid LTs from 2008 for example. Norco acknowledged the issue, and warrantied the seatstay assemblies.
I had the same experience with the 2011 Brodie Mettle I was riding yesterday and thought of this issue.
Why slag free swag?:rolleyes:
ummm, as your doctor i recommend against riding with a scaphoid fracture.
organics aren't as powerful and they wear out faster and they fade easy.
Well, you got one e-fact out of three right ;)
treezz
wow you are a ass
out of curiosity, alignment of caliper / rotor any how related to the brake power/ drag? feeling a lot of drag and loss of power on my 775 xt brakes, and it squeals like chewbaca now too ugh
or maybe shimano 8" rotors are shitty =/
A little feedback for those who are interested. Alignment seems to have worked, no more squealing or vibration.
Forget the loosen the bolts, then tighten the bolts while squeezing the brake lever method. It doesn't work for the elixirs. As suggested in earlier posts, centering the rotor by eye seems to be the best method.
Thanks for everyone's suggestions, its nice to not wake the dead every time I touch the brake.
I just built up a 2010 Enduro S-Works and my rear Elixir CR is making the same horrifying reverberation sound. Fanatyk Co says it's due to a wide range of possible issues. The main ones being tab alignment and flex (2010 and 2011 Enduro rear ends are not post-mount). I suspect this is true because the same brake on my Delirium was perfectly silent.
So I'm going to double-check the tab alignment and source one of those solid rotors.
There's nothing better than an Orangina after cheating death with Digger.
Damn, the answer was so obvious I should have thought of it myself! I better give the front brake a spray while I'm at it.
When I worked in a bike shop ages ago, i met more than few customers who had oiled their rims to try to eliminate (rim) brake noise!
The Elixir Rs that I have on my flatline are dead silent. Never had a noise issue.
I just built up a 2010 Enduro S-Works and my rear Elixir CR is making the same horrifying reverberation sound. Fanatyk Co says it's due to a wide range of possible issues. The main ones being tab alignment and flex (2010 and 2011 Enduro rear ends are not post-mount). I suspect this is true because the same brake on my Delirium was perfectly silent.
So I'm going to double-check the tab alignment and source one of those solid rotors.
My '11 Enduro with Elixir R SL's has had no noise issues at all.
I would like to suggest that brake vibration is a resonance one, but that it requires frame and brake parts to conspire together to produce it. Hence, sometimes fiddling with the brake parts fixes the problem.
The main reason that I think that vibration usually involves the frame can be illustrated by the question: How often is it the REAR brake that causes the problem? My guess is that it is almost always the rear brake. Note that on the FRONT wheel, the action of the suspension is exactly perpendicular to the torques produced by the brake, and so there are no brake and suspension interference problems at the front wheel. This is why you never hear of Brake Jack on the front wheel; it doesn't exist.
I have just bought a Trek Remedy and it has rear brake vibration. Nothing serious but a little annoying. In my opinion, the Trek's ABP rear pivot sets up interesting and opposing forces in Brake Induced Suspension Interference (Brake jack). As the suspension goes through the initial part of its travel, the rear brake tries to move forward. This would normally cause brake Squat. However, that is not the end of the story, because when the brake is applied it also imposes a torque on the seat stays (because the brake is attached to the seat stays). Because of the angle that the seat stays attach to the rocker, this torque acts to deactivate the suspension (brake Jack). Presumably Trek did this on purpose; the two actions of the brake on the suspension are opposed and so cancel each other out - probably not completely, but at least in part.
Now, obviously, if there is a small amount of slack in the bushings between rear suspension parts, it is conceivable that the brake can catch and release the rotor many times a second; this is felt as vibration.
I also have a '96 Stinky, but replacement bushings are too expensive to warrant me buying them. So I jam drinking straws over the bolts that go through the bushings. Because they're only drinking straws they wear out after a while and I have to repeat the process. And here's the important bit: when I insert new straws (and so remove the slack) the vibrations stop, and when the straws wear away - like they are at present - I get lots of vibration from the rear brake.
I imagine that it is a rather hit and miss thing. Maybe you receive a frame that has a little more or less slack than the average, or maybe there is more slack on one side of your bike than the other. All of these detailed vagaries can sometimes conspire to cause brake vibration.
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