I don't know what else to call it, but the rear brake will make a noise and cause a vibration up through the handlebars. They are Avid Juicy 7's. I've replaced the pads several times, adjusted the caliper, replaced the rotor, replaced the skewer. Nothing changes it. I took the entire wheel off and put it on another bike and it did the same thing. When I put a different wheel on my bike, no problem. Put my wheel back on, there the problem is. It's a Mavic crossmax SL with the aero spokes, and I think the problem is in the wheel somehow. I've had it trued and the spokes tightened, and the bearings adjusted, still the same problem. I'm still convinced it is the wheel but I don't know what else to do. Any thoughts?
Brake jack
- Thread starter joeba
- Start date
Don't brake so much?
Also, it might be the stiffness of the wheel.
Also, it might be the stiffness of the wheel.
Sounds like it might be a harmonics problem. Like the vibrations made by the brakes match the natural harmonics of the spokes, which then vibrate like crazy and make the whole bike shake. The spokes on that wheel probably don't touch each other? To test this, use some tape to connect pairs of spokes together and test ride.
I do think it is some sort of harmonics thing. I'll try the tape on the crossing spokes. One more piece of the puzzle, everything was fine for an entire year, second year on the bike and it starts. It's an Ellsworth Truth, and I did replace the drive train at the beginning of the season. Any more thoughts?
Thanks
Thanks
I asked my friend who uses Juicys about the "brake warble" problem that I've read about on the internet. He said that on the earlier Avid rotors the rotor's spokes swept the pad and every time a spoke came by the pad it created a vibration. The newest generation Avid rotor shortened the spokes and lowered the main rotor surface solving the problem.
When you said the problem went away while using a different wheel I assume that means you were using a different rotor, hence no spokes catching the pad.
Buy new rotors. I think they're called "G3", as in 3rd generation.
When you said the problem went away while using a different wheel I assume that means you were using a different rotor, hence no spokes catching the pad.
Buy new rotors. I think they're called "G3", as in 3rd generation.
These are only $13 each so it could be a cheap way to fix your problem. They are very light and work great with my XT and XTR brake calipers. They are pretty popular so if they don't work any better you won't have much trouble selling them.
Also, here's your chance to go up in rotor size if you've been thinking about it. I use 6" for XC, 7" for FR, and 8" for DH.
http://www.pricepoint.com/detail/16245-115_ALISR7-3-Parts-158-Brakes/Disc/Alligator-Serration-Disc-Brake-Rotor.htm
Also, here's your chance to go up in rotor size if you've been thinking about it. I use 6" for XC, 7" for FR, and 8" for DH.
http://www.pricepoint.com/detail/16245-115_ALISR7-3-Parts-158-Brakes/Disc/Alligator-Serration-Disc-Brake-Rotor.htm
They make products for motorcycles that is a sort of metallic paint that you put on the rotors to stop squeal. I have used this a couple of times very successfully and a couple of times with no change. There can only be a harmonic response if the rotors are vibrating. And the only way for them to start vibrating is if there's something up in the system. I will second the movement toward the Avid G3 rotor, it's a big improvement over the old ones (especially the clean sweep).
I just picked up an alligator front rotor the other day.
Maybe now you can keep up with me, Matt. We'll find out Sunday.
I don't want to sound dumb, but if the problem is the rotor, why has it not always been there. Also, my girlfriend has the same bike and set up, but with different wheels, same brake and rotors, but no problems. For now I have replaced the Mavic wheel with a DT Swiss/Specialized off one of my other bikes. new rotor that I already had and the exact same model as the original. So far no trouble. I'm about to say screw it and just get new wheels. Stan's Olympic's?
If you have gotten any kind of contanimation on your rotor at any time then you will continue to spread whatever it is on every set of new pads you get. It's simple as riding through a puddle that a 2 stroke had went though before you or washing chain lube off the chain and over the rotor.
There is no wheel what will cause your brakes to do that. The braking surface is what is vibrating, so you need to determine what is vibrating in your braking system. Other options is a worn rotor, poor caliper alignment, poorly faced disc tabs, you could even try putting some score lines on your pads.
Have you tried both the organic and sintered pads? Sometimes can change the way the brake behaves. Sintered comes standard on 7s in most cases, so you can look for the black organic material pads.
Remember, every time you change your pads you should be cleaning the rotor with Isopropyl alcohol. If not, you're transferring all the grime and crap to your new pads and creating the exact same problem over and over again.
Though if you continue to not believe what several people have already told you, then I can offer up my actual thought: you're dealing with Avid brakes on an Ellsworthless, things aren't looking good for you.
There is no wheel what will cause your brakes to do that. The braking surface is what is vibrating, so you need to determine what is vibrating in your braking system. Other options is a worn rotor, poor caliper alignment, poorly faced disc tabs, you could even try putting some score lines on your pads.
Have you tried both the organic and sintered pads? Sometimes can change the way the brake behaves. Sintered comes standard on 7s in most cases, so you can look for the black organic material pads.
Remember, every time you change your pads you should be cleaning the rotor with Isopropyl alcohol. If not, you're transferring all the grime and crap to your new pads and creating the exact same problem over and over again.
Though if you continue to not believe what several people have already told you, then I can offer up my actual thought: you're dealing with Avid brakes on an Ellsworthless, things aren't looking good for you.