harihari

I am having trouble getting rid of massive brake squeal ont he front brake sof my 'cross bike, a Jake with carbon forks. I have carefully aligned the pads-- they are not pressing air or tire, and they are lined up right. No wobble int he wheels or fork.

Any suggestions on hwo to get rid of the immensely loud squeal?


chris

AEO

have you toed in the pads?
what make is the canti?
avid cantis are notorious for squealing.

harihari

The pads are aligned, ie when you pull on the brakes, they press on the rim. They aren't at any angle, they don't hit the tire, there isn't a part of them that misses the rim, etc.

The brakes are avid shorty 4s and I have shimano pads on them.

AEO

toe in
https://www.parktool.com/repair/readhowto.asp?id=19

harihari

wow, thanks. I will put the thing up on the stand and fiddle tonight. Very much appreciated.


chris

Stealth TDI

Hello,

I just got new pads for my V-brakes. Not sure if it matters between canti and V's since aligning the pads should be similar. I followed the directions above (but found the V-brake page) and STILL get squealing from the front brakes. Do new pads sometimes squeal and then stop once bedded-in? I stopped the rear squeal with excessive toe-in. But the front ones seem hopeless. Does anyone have advice?

Thanks,

Scott

BCRider

For 99.9% of the cases some toe in will help. For some rare times and when you find that toe in seems to make things WORSE try some toe OUT. I know it sounds counter-intuitive if you consider why toe IN reduces squeal but for some cases all the factors add up and toe OUT will do the trick where nothing else helps.

The whole point is to alter the mechanical frequency and how the friction curve builds up. Sometimes you just have to go against the conceptual model to make the factors all play nicely and silently.

harihari

YOu should also clean the rims thoroughly . ALso make sure there's no looseness in the fork, hub etc. I used quite a bit of toe-in to fix mine; now they are perfect.

AEO

I find dirty rims sequel less.

ever heard of squeaky clean plates?

simplify

Some pads are just immune to all efforts at silencing them. I tried everything to quiet the squealing on a very nice set of v-brakes (Avid single-digit 7's). Changing to Kool-Stop Tectonic pads did the trick. Front and rear, best braking ever, and totally silent. Nothing I tried would stop those Avid pads from screaming.

Stealth TDI

Hello,

Sorry I hadn't thanked you for your replies earlier. I didn't receive e-mail notices from the forums right away; and then I couldn't post replies for a day or two. Weird. Anyway, some of the details I left out above: New pads are Kool-Stop black pads. The rims were quite dirty. Rubbing alcohol wasn't quite enough to clean off the contaminents. So I ran a piece of 2000-grit sand paper along the braking surface by hand (finger?). I can imagine the rims are "too clean" now. Perhaps the squealing will subside over time as the rim starts to collect material from the pads? Time will tell.

The good news is these pads are effective enough that I don't have to apply as much pressure to slow the bike (currently riding on the road). The squealing doesn't begin unless I'm really getting into the brakes.

Thanks for your thoughts.

Scott

Yan 

I solved my sqealing problem by switching to Velo Orange Sqeal Free pads. Koolstop salmons squealed even worse than stock Shimano pads. Cleaning the rim is futile because it just gets dirty again.

MichaelW

Ive just bought an "uphanger" to replace my headset-mounted down hanger. They are reputed to prevent judder in forks with bendy steerers. Im using it to clean up my cable run. I'll post a review ASAP.

Cynikal 

Specialized just started using those on the new Crux. If you read what Zinn says causes shudder/squeal, it should work.

Also, a mechanic once told me to use 2 different brake pads on each brake. Shudder/squeals are caused by the same factors but at different frequencies. Using different pads disrupts the symmetry of the frequency thus eliminating shudder/squeal. Haven't tried it my self but it's worth a shot.

Stealth TDI

Update: Something I read above compelled me to check the fit between the brake arms and the mounting studs. There was a little slop. These brakes are old Shimanos with no trim level. I was unable to "tighten up" the fit. I found a set of XTR V-brakes on sale for $35ea. So I made the jump and replaced the brakes altogether. Squeak-free and good stopping power.

34505838

i have dia-compe 987 cantilever brakes and with the original pads they were always squealing i switched to kool stop dual compound thinline pads (also might have used other pads before that) and i was getting shuddering and squealing i read somewhere that shorter pads do this less often (for brake shudder) so i switched to short block shimano pads from a cheapo bike (50mm in length) and the shuddering stopped i could get the squealing to stop but would never last more than a few weeks at most starts squealing again so i would keep adjusting them but even with toe in still there they would squeal - one thing i noticed through all this is it doesn't make a difference whether i place the pads forward or backwards in direction sometimes backwards would be better so i started removing the pads when i adjusted and checking the shape of the pad wear for which way to place them so then after reading this i was going to try toe out but i noticed my pads hadn't worn the same on both pads (switching back and forth) so i did it like this one toe in and one side toe out and so far so good (ois quiet) i will see how long it lasts

Daniel4

Zombie thread.

I like squealing brakes. They warn the pedestrians who don't pay attention to my bell. And I like to think it gives motorists who cut me off a little scare.

capnjonny 

Make sure the rims are clean . Wipe with alcohol and a clean white rag till it stays white.

Sand the rim with 1000 grit wet/dry paper then clean again with alcohol.

Clean off the brake pads. Take some 400 grit wet/dry paper and scuff them up then wipe with alcohol.

Toe in the brake pads by inserting a credit card between the back of the pad and the rim while adjusting.

Make sure the pad is angled properly to make full contact with the rim in front with the credit card wedged between the rim and pad in back.

make sure the wheel bearings are adjusted perfectly

Make sure the wheel is centered in the fork.

That is all I can think of.

corrado33

I agree here. I've found that on some cheap brakes (with excessive slop or arms that are easily bent) tend to do well with toe OUT. Dunno why. I've never noticed the same thing on nice brakes.

34505838

update: i did the one pad toe in the other pad toe out and it was completely quiet it has been completely quiet but now my front brake has started shuddering mostly when i brake with only one hand on the handlebars - this is a pretty regular event for me i brake and drink from my water bottle at the same time - and also started shuddering with both hands too, and shuddering never happened before with these brake pads

Bill Kapaun

Reduce the amount of toe out on that pad.
I think if you just visualize what is happening, you'll see the problem.
The rim is "grabbing" the pad with it, because it's kind of "wedging in".
Pad can only go so far and "snaps" back.

Ghazmh

Do new rim/brakes squeal normally? Will it go away as the pads wear in? I have a new Boon 7 with TRP canti's, approx 50 miles. The rears are quieting down but the fronts are as frighteningly loud as ever.

Ferrouscious 

My Kool Stops took about 3 descents down my local steep hill to be silent. I would say that if they are good quality pads, then as soon as the original manufacturing coatings and residues wear off they should be silent. Sanding them slightly (the pads in my experience) helps speed that up. Avid brake pads are notorious for squealing like a dying pig.

34505838

okay so i mentioned above in the update that i did one side toe in and one side toe out then they started shuddering one handed but being lazy i didn't actually do anything after that and then the shuddering went away (after about two or three rides) and they have been fine since i haven't adjusted anything since (supposedly these brakes are common for front brake squeal shudder) this is by far the longest i've ever gone without any problems on this bike (brakes)

Andrew R Stewart 

Any carbon steerers involved with the squealing/shuddering ft brake? It's a well known issue of the steerer flexing then rebounding. This effectively is pulling then releasing the cable tension causing the pads to grab and release then grab again in very short time intervals. This is actually the same pad/rim interaction that causes squealing with all bikes that do so. Just the steerers (that are stiffer) don't contribute as much to the problem. Andy