Bicycle Mechanics - Canti-Brake Problem

Ok so this has got me a bit confused...

When I bought my Surly Cross Check I had severe squealing on the front brake. I replaced brake pads twice, took it to two shops and the second could only fix it by creating a HUGE toe-in on one of the pads (and shortening the cable a bit). It seems a bit odd but it worked at the time, even if my stopping power wasn't what it should have been.

Now that I'm riding in the rain, it seems that water and dirt are getting caught up at one of the pads since it is only about 1mm (max) away from the rim, causing one hell of an odd sound when riding and affecting stopping power when I apply the brake. The odd thing is that the other side has more than enough distance between the pad and the rim and it isn't the position of the pads or a difference in the tension of the return spring. I checked, and when I use the canti-brake, the brake arms return asymmetrically, with one being farther from the rim than the other, even if they don't start out that way.

Sorry, but I can't get any photos right now. Anyone have any ideas?

You're best to learn the art of cantilever setup yourself. Start here. http://www.sheldonbrown.com/canti-trad.html

Excessive toeing in is not a solution for squealing as it compromises the effectiveness of the brakes. Kool Stop Salmon, or similar pad helps reduce squeal, but is no sub for proper setup.

I know, I only did that as a last resort. I have read the Sheldon Brown site on setup and I worked for a LONG time on it. I did use coolstops, but black not salmon. I just got fed up and took it another shop just now, people seem to like them a lot. I will get back to ya tomorrow... mechanic thought it may be an issue with the brake mechanism itself................. oy

hmm.. grease the canti posts?? I dont actually know if that will work, but maybe its a combination of the vibration making your posts act like a tuning fork??

I'd be looking for some fault in the canti posts or the actual levers, the ones at the rim, not the handlebars. Assuming it can't be adjusted out.

The good news/bad new about canti's is they are infinitely adjustable!

I use the traditional post type pad canti, which can be sensitive to the placement of the pad along the length of the post. In general, I find if the pad has to reach more than half the length of the post, there's going to be trouble.

Then you've got the yoke cable and it's limitless possibilities of angles. This can maddening, as rules of thumb don't always work.

My go-to for trouble brakes when I need a break from it is to use my vintage Shimano wide profile canti, which never squeals. I did this when I couldn't get some Suntour XC Pro "low profile" canti's to not squeal, after years of squeal-free service. Instead of fretting anymore, I replaced it with my old wide profile cant. I've since gone back to it, with Salmon pads and a new perspective, and solved it.

So, if it's a real bear, get some wide profile canti's, either as a temporary or permanent solution. Tektro CR720 are as inexpensive as it gets, and most people like them, though I've not tried them myself.

Another cantilever brake that seems to work well, powerful and quiet, are Shimano's BR-R550. They use a V-brake type pad and holder and are very simple to set up. I have them on a Cross Check and they have been the best (and quietest) cantis I have ever installed and used. They aren't expensive either.

What headset are you using?

Try this (it worked for me):

http://www.amazon.com/Tektro-Brake-Housing-1272AF-Silver/dp/B000C14HNS/ref=sr_1_11?ie=UTF8&qid=1278708703&sr=8-11-spell

get the fork mounted cable hanger

I used this front cable hanger on my Cross Check: http://www.jensonusa.com/store/product/CA307A00-Tektro+Frt+Cable+Hanger.aspx

I installs like a spacer above the headset's top race and below the strem. It's very rigid and solid feeling with no give or flex.

Sloppy fit on the frame pivot?

cheap price point spec parts at the expense of QC...

There must be some squeal in the air ...... even my supposedly fixed rear XC Pro canti's squealed like a pig today. Switched back to my trusted wide profile canti's..... same friggin' squeal. They squeal just moving the pads a few inches when pressure is applied.

All this is very humbling, because these are brakes that I've been using for 10 years without issue. It seems the powers that be decided it's time to make some noise, and there's not a damm thing I can do about it.
I've made every type of adjustment I could to pad position, cable length and all angles. Salmon pads ..... ha ha ..... they're just as loud as any other pad. I'd call them a bust for noise reduction.

Sometimes ..... stuff happens. My last resort will be VO's squeal free pads.

The funny thing is, the front XC Pro canti still has the original Sun Tour pads installed, and it's never mad a pip. I go back to the rear brake, install the some worn original Shimano pads from 1984. Yes, they're that old. Squeal stopped. I'm thinking Kool Stop pads are much over rated. They make the Salmons idiot proof for toe in their shape, so this is never an issue with them.

I think I'll give some VO Squeal free pads a shot. http://www.velo-orange.com/vosqfrbrshan.html