stroker trails / magura storm sl rotors
all new with 2 rides and the first did not reveal any issues but my 2nd such 2hr ride uncovered the dreaded turkey warble on both F&R. The discs are centered and not pushed to either side when applying brakes, sintered pads that I chamfered the leading edge in an effort to cure the noise but to no avail. Is it possible the pad/disc combo just aren't compatible??
My only other thought is replacing the pads with organics....help mr wizard!!!
Did you "bed" them?
The manufacturer usually specifies a series of brake applications to break in new pads.
Something like "apply brakes at medium pressure 10 times while riding at moderate speed".
I had the same problem with my Avid X0 brakes. Bought a new set of organic pads (same as stock) and bedded them in per instructions. Didn't work for me. Then replaced the organic pads with sintered (opposite of yours). That did the trick for me. Good thing, cuz next step woulda been Hope brakes at around $500.
honestly if there's a weak link in the armour this would be it sadly and yes hayes speaks of the 'bed' process on paper and vids. I have 1 new pr for the front i'm going to try with the proper method and see if it works thanks.
Originally Posted by SmooveP
per Hayes PDF.
Disc brakes require a special burnish period to achieve maximum braking power.
This burnish period last for about 30-40 stops. During this period some noise may occur.
The method I learned for breaking in pads was from metallic moto stuff:
Get up to speed, brake hard - repeat 10 times.
What I've learned with bike stuff: The more you let them learn to sing - the more that pattern gets imprinted on the rotor and the more they sing. If, despite a good original "bed", they start to sing - don't let them! Usually the warble starts at partial/light brake loads - if it starts, shift your weight back and hit 'em hard! Don't do any "light" braking for a while if you can avoid it. Braking in hard pulses is good (not locking the wheels, weight back)
If you have let them learn how to sing well, you may need to take the rotor off and erase that music - by taking a sheet of sandpaper on a hard/flat surface and "lapping" the rotor (lightly hold it against the paper and randomly wiggle it about) until you've got a uniformly sanded surface. 200grit works well. I bought a used Hope "gothic" rotor that sang like mad - this and bedding fixt it. Quiet ever since.
Fatbikes are much more fun than they should be allowed to be!
WSS/OSS: open source sealant
imma cut the vocal cords then.... perhaps I begin anew then with diligence thank you kindly.
I have yet to run across a set of stroker trails that don't pulse or squeal with either the metallic or semi-metallic hayes pads. I've had 3 sets and I love the lever feel and braking power but I've never got them to be very smooth or quiet. I talked with Hayes about it on the first pair and they sent me a pair of semi-metallic pads and told me that should help the problem. It does but doesn't fix it. I've ran the stock Hayes Rotors and Magura Marta SL rotors.
If you clean them and try to bed them in properly you may be able to get them to a tolerable noise and pulse level but I'll be impressed if you get it to go away and I'd love to know how you did it if you do.
Woodi any thoughts about aftermarket organic pads? i.e. swiss stop, vesrah?
kind of a band aid but hitting the rotors with a little of this before each ride might help, it's a bit better than alcohol
The rotors and brake combo should not be a problem. Anytime you have noise its due to vibrations and that can be contamination on the pads or rotors or both or ..... alignment of the caliper is not accurate.
If these brakes were already on the bike and you added new pads and rotors, then you need to wear the pads into that "bias" or "plane" of the rotor until the noise stops and that depends on how much vertical descending or how much your braking needs may be.
If your typical rides are somewhat flat, then it will take forever to quite the noise but if you live and ride a lot of mountainous terrain, then the wear is quickened and the noise goes away sooner.
Otherwise, find a shop with a "disc tab facing tool" to machine the tabs on the frame and fork. Otherwise you will always fight the noise once new pads are again installed.
Per Hayes tech support moments ago:
Remove wheel, remove pads and use a flat file on a flat surface to remove the glaze from them due to my rather easy bed process then clean with alcohol, reinstall and do many hard stops from 10-15mph. His reasoning behind the file as opposed to sandpaper / emery cloth is the adhesive used can transfer to the pad therefore introducing yet another variable into the mix and end (his analogy) up like 2 pieces of glass rubbing against each other which gives a squealing sound....made sense to me.
the brakes, bike, fork etc are all new and ridden only 2 times with the 2nd ride revealing the noises. I suspect the disc tab facing tool is very much like the ones i had them use to chase/face the BB shell & steerer tube before assem yes??
Originally Posted by judemonica
Post mount (which you have) pretty much eliminates the need for this. Loosen the post mount bolts, squeeze the lever and retighten the bolts while keeping the lever squeezed. This "auto aligns" the brakes laterally.
Originally Posted by nvphatty
I've done this method with varied results, ie when applying the brakes the disc is still pushed to one side a minor amount therefor i adjust the caliper by hand so this does not happen...perhaps a mistake on my part to mess with it after the auto align??
Originally Posted by SmooveP
Yeah, you can go insane trying to get it perfect, because one piston travels more/less than the other side, some dropouts are fussy, etc. It doesn't have to be perfect, because the pads will wear and self-align somewhat.
Originally Posted by nvphatty
Pad compounds and contamination seem to cause more grief than alignment when it comes to noise and/or pulsation. I've had luck in the past with EBC brand pads, but there's no guarantee they will work for you. If you browse the Brake forum, you'll see the advice is all over the place.
They suggest 50 stops on the Prime before you go for a ride. It's a pain but it works.
I have struggled with this for some months now and while i've tried some recommended tips n tricks none worked...........until yesterday / today with a 12mi test ride....wait for it!! WAIT!!
ok i removed the organic pads and installed used sintered pads, installed a used 185 avid CS rotor i had in a box and reassembled the front wheel and headed down the driveway /street to test, after 10 stops not 1 revealed the warble squeal, ok so far so good. fast forward to todays test ride of some 12mi of varied terrain including a steep decent of roughly 1/4mi while modulating the brakes and it never faded, squealed as it had in the past on the very same trail.
So where does this leave me? well is it the increased rotor size effecting the harmonics or perhaps the avid rotor having thicker spokes than the magura storm rotor or both??
If anyone with some sort of engineering background can enlighten me and others regarding the results please do chime in.