TakingMyTime

I just put together my new Canyon and the front disc sounds like a roaring elephant. This was a brand new build, I was careful not to touch or contaminate anything and the disc is "true". Help! Everything I read online is either the rotor is bent or the brakes are dirty (which neither is).

Mojo31

Did you bed them in?

rydabent

Everyone knows about toeing in rim brakes, and the calipers on disc brakes need a slight toeing in also on their mounts.

cxwrench

You don't actually know what you're talking about, do you? This is one of the most ridiculous things I've ever read here. No, the caliper does not need to be, nor can they be 'toed' in or out. They need to be dead straight/parallel to the rotor and perfectly centered over it.
For the OP: generally the noise comes from contamination. You can sand/clean the rotor. I use a Mavic abrasive block and then alcohol. Once pads are contaminated there is nothing you can do except replace them. You can try sanding the surface with sandpaper or drywall screen but they are so porous that if anything get on them it goes through them very quickly, especially if they get hot. One last thing, metallic compound pads are noisier than resin/organic...to the point that SRAM describes metallic pads as 'powerful/wet conditions' and organic pads as 'quiet'...right on the package.

BTinNYC 

Cxwrench is a reliable source of fix info. I like the bedding video too, wished I knew that before.

On my recent Canyon, early on I heard a brake rub and did a 3 min re-align and done. Might work for you too.

Loosen both bolts enough so the brake can move (4mm hex) but not loosey goosey. Squeeze and hold the brake lever, re-tighten while holding the brake. Alignment fini.

Rick

If after all the cleaning, adjusting and even replacing brake pads ,you still have squeaky brakes. Replace the rotors with ebike rated rotors.

TakingMyTime

I'll be pulling the front wheel later today and do a thorough inspection, cleaning and then a quick alignment to ensure I've covered everything. These started screaming almost immediately before any mileage was put on the bike. I can't think they got that dirty just on the street in front of my house. Anyway, we'll see. I'd hate to think I'm going to have to purchase new pads for a bike that is only hours old.

cxwrench

Take it to your local Canyon dealer...oh wait...

rydabent

Damn strange when I changed the caliper mount by less than 10 thousands of an inch my squeal was gone.

I have found that there are a lot of know it alls or claim to know it all about bikes, really dont!!!

Rick

Disk brakes are high maintenance and very touchy. They added many new complications to an otherwise simple machine.

cxwrench

I'm quite sure that I have forgotten more about disc brakes in general and bicycle disc brakes in particular than you'll ever come close to knowing. What you're talking about is not 'toeing' It's 'adjusting' or more properly 'centering'. You cannot physically 'toe' a disc brake.

Rogerogeroge

You figure you've gotten all of the mileage you can out of the Cycling Pants thread?

rydabent

Just different adjustments. There really isnt anything on a bike that is hard to adjust or do.

BTW some of the machines I worked on before I retired require adjustments down to 5/10,000ths or even less, so adjusting a bike is a piece of cake for me.

rydabent

Since you posted that, I would say you are right about forgetting how to totally and properly adjust the calipers on a disc brake bike. As I posted on another thread, I worked on machines that required adjustment down to 5/10,000th of an inch or less.

Lets do caliper adjustment 101. Center them with washers or shims, and then shim for a very slight wider entry of the disc into the caliper. As I posted it got rid of my squealing discs that way. There you are, if you read that and understood that sentence you passed disc brakes 101, send me your $100 and I will send you your diploma.

Rolla

You’re either doing it wrong or you have lousy brakes. I haven’t touched mine in months, and they’re silent, strong, and dialed.

TakingMyTime

During closer inspection I noticed that mineral oil was weeping from the intake nipple of the disc caliper. The bleed screw was torqued properly but when squeezing the brake lever a drop would begin to appear at the nipple. Canyon first suggested I take it and have it bled and new pads put on (on their dime) but my LBS said they do not think that was going to fix the leak. I called Canyon back and they agreed and will be treating the caliper as a warranty claim and sending me a new one, including pads and rotor to be installed at my LBS on their dime.

I have to say that Canyon handled this like champs. Their customer service is nothing short of incredible.

cxwrench

How about this...there haven't been shims used to adjust disc brakes for 15 years. It really appears you know little to nothing about disc brakes. You're just steering people the wrong way talking about things that haven't been the norm for years and years.

Koyote

Complete and utter nonsense. It's not even possible to 'toe in' the pads in a disc brake caliper.

PS: I'm STILL waiting for you to show is this mythical bike that has "36 or more" speeds.

Koyote

Have you ever owned a bike that has disc brakes?

Rick

[QUOTE][Have you ever owned a bike that has disc brakes?/QUOTE]

I have three disk brake bicycles.

Have you ever owned a bicycle with hydraulic rim brakes?

Canker

Well I'll just throw this out there to cause more controversy since that is what this thread has turned into
You can clean contaminated pads. You just have to heat them up to using a propane/map torch to burn off any contamination. Done it multiple times. I'm sure there is some risk of melting whatever glue, epoxy, whatever holds the pad material to the backing plate but they are made to stand up to serious heat anyway so for me it is worth the risk. And worst comes to worst and ones fails during a ride I have have two brakes. I also sand the top layer of pad material off whether I need to or not, doesn't hurt.

Koyote

What sorts of complications have you experienced with disc brakes? I'm genuinely curious.


​​​​​​That's got nothing to do with the thread topic.

rydabent

There are washer on disc brake caliper mounts. They can also be known a shims. Time to up you knowledge on disc brakes.

Koyote

Oh, good grief. Those are mounting washers, and they don't allow you to toe-in the pads.

This is beyond ridiculous. You're parodying yourself.

cxwrench

I'm not normally the kind of person that reports posts but I'm very close with you. You genuinely have no idea how disc brakes work yet you continue to post bad advice. I'm not the only one that's commented on this. Face facts...you're wrong, very wrong.