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Steve
02-26-2014, 10:36 AM
During these cold days, sometimes my disc brakes (Avid BB7s) are really loud. I removed the brake pads and cleaned inside to make sure it wasn't road crud inside the brake assembly, but then again today it was super loud at times. It seems like if I've been braking a lot, the noise is less (perhaps because it is warmer).

Anyways, is this normal just because of the cold? Or might I have an issue?

thanks!

jabberwocky
02-26-2014, 10:39 AM
As a longtime user of Avid discs, I'd say you're more likely to have a problem when they are being quiet. ;)

Tim Kelley
02-26-2014, 10:44 AM
My disc brakes get loud when they are wet.

It gives the pedestrians in the crosswalk a heads up that you're coming!

mstone
02-26-2014, 11:06 AM
During these cold days, sometimes my disc brakes (Avid BB7s) are really loud. I removed the brake pads and cleaned inside to make sure it wasn't road crud inside the brake assembly, but then again today it was super loud at times. It seems like if I've been braking a lot, the noise is less (perhaps because it is warmer).

Most brake rotors will start getting some surface corrosion pretty quickly, especially in this kind of weather. If you stop hard a few times and get the rotors polished to a shine they should quiet down. (Or, more than a few times. I had one bike garaged for a month or two and then went out for a ride with the kids--drove them nuts as I kept hammering the brakes like a dying goose until they were cleaned off.) The same thing happens on automobile or train brakes, but there's so much more force involved that the crud burns off almost instantly.

Edit to add: the above is for dry brakes. Wet rotors will be louder until they dry, which takes a while in the rain.

hozn
02-26-2014, 11:17 AM
My disc brakes are really loud when wet. Sometimes it's embarrassing when I terrify a pedestrian by lightly braking. I think this can also be mitigated by using different (e.g. organic) pad compounds, but at the cost of not lasting as long (esp. in extreme conditions). Anyway, I'm ok with them being loud. As mstone notes they get a bit quieter after the first few hard braking, though I find they typically remain rather loud for the entirety of my commute (~1 hour).

dasgeh
02-26-2014, 11:31 AM
had one bike garaged for a month or two and then went out for a ride with the kids--drove them nuts as I kept hammering the brakes like a dying goose until they were cleaned off.

Now I'm imagining all the things our kids would write if they had a forum like this to gripe on...

Steve
02-26-2014, 11:35 AM
Thank you all. I feel much better now.

Greenbelt
02-26-2014, 11:48 AM
My disc brakes get loud when they are wet.

It gives the pedestrians in the crosswalk a heads up that you're coming!

Loud brakes = feature, not bug.

The cantilevers on my cross bike make an ungodly racket. Just the way I like it.

jabberwocky
02-26-2014, 12:22 PM
You can try different pads. I found aftermarket pads better than the stock Avids for the most part (though all my stock pads are 5 year old vintage, so I have no idea what the pads on their newer brakes are like). My favorite pads for my various Juicys (which use the same pads as BB7s) are EBC Golds, which are a sintered metallic pad. Hard on rotors, but they do last a very long time and generate very strong braking force. They also aren't as squealy as some of the organic pads, though they can make an odd grinding noise under hard braking.

I've heard conflicting things over the years about using sintered pads in mechanical brakes; some places say its fine, some say they generate too much heat. So take that with a grain of salt.

All that said, I've learned that as long as the brakes are doing their job, I tend to ignore noise. I've had several sets of Avids (mech and hydro), Hayes, and Formula discs. They all squeal under certain circumstances.

Amalitza
02-26-2014, 01:22 PM
My disc brakes are really loud when wet. Sometimes it's embarrassing when I terrify a pedestrian by lightly braking.



My disc brakes get loud when they are wet.

It gives the pedestrians in the crosswalk a heads up that you're coming!



Edit to add: the above is for dry brakes. Wet rotors will be louder until they dry, which takes a while in the rain.


Everybody keeps saying this. My disc brakes are loud and squealy when dry and generally nice and quiet when wet. :confused::confused:

(btw, startling pedestrians is fine, but i find mine even more useful for giving the kamikaze squirrells due notice.)

mstone
02-26-2014, 01:32 PM
Everybody keeps saying this. My disc brakes are loud and squealy when dry and generally nice and quiet when wet. :confused::confused:

Maybe you should try oiling them so they're quiet all the time? Note: don't try this.

Harry Meatmotor
03-27-2014, 07:05 AM
as mentioned earlier in the thread, ponying up for some sintered metal pads will probably alleviate quite a bit of brake squawk, but to the detriment of the rotors.

general observation: Avid rotors are typically kinda crummy, but they're relatively inexpensive.

Usually, noisy (organic pad material) brakes indicate some fouling of either the rotor or the pads. First thing to check is to make sure there's no debris stuck in the pads - if there are tiny chunks of anything stuck in the pads, use a pin to pick them out. Another trick is to go down to the car parts store and pick up a can of brake cleaner (and get the not-so-safe for the environment stuff. the "safe" stuff is junk and despite the label, it isn't "safe" for anything... also, don't waste your money on any "bicycle" brake cleaner, it's hugely overpriced). With the wheels off the bike, spray down both sides of the rotor, and keep a shop rag over the hub so as to NOT spray the bearings. Then, carefully give a couple squirts of brake cleaner on the pads and let everything evaporate.

Pop the wheels back in the bike and take it for a spin. you're going to want to "bed" the pads to the rotor by getting some heat into both the pads and rotor. you'll do this by either doing several hard stops from speed, or finding a big long hill and constantly, lightly brake. what's going on here is that some of the pad material is going to stick to the rotor and some of the rotor is going to stick to the pads. when some crud gets on the rotor (especially anything with any kind of petroleum base, i.e., oil or grease) or the rotor is sparkly clean, the pads/rotor are going to make noise. Once there's a good amount of pad material that's transferred to the rotor, you're usually gonna get nice and quiet brakes. However, it only takes splashing through a puddle or two to wash some of that pad material off, and get some crud on the rotor. None of that will really negatively affect the power of the brakes, but it will make them noisier.

Pro Tip: a quick way to clean your rotors and get some pad material back on the rotors (while you're riding) is to take your water bottle and squirt some water (NOT PURPLE SPORTS DRANK) at the caliper, while you're applying some pressure to the brakes. then, keep applying light pressure until the water has evaporated due to heat.