robertj298 

I put some cool stop pads on Miyata 615 and they vastly improved braking but now my brakes squeal like a stuck hog..I can't figure out how to toe then in

TenGrainBread 

There are two methods...

1. The proper way with post mount brakes: file a deeper divot into the eye-bolt washer under the brake pad, on the side facing the wheel. The deeper the divot filed, the more the brake pad will toe when tightened.

2. Bend the brake pad posts. Might break. Not recommended.

oneclick 

Brake squeal is a result of the stick-slip frequency of the pad/rim interface being sympathetically resonant with some part of the brake structure.

You can attempt to change the resonance point by stiffening up the structure (loosening it may work but is not recommended for other more important considerations).

You can attempt to change the stick-slip frequency by altering the contact surface - toe-ing in may do this, but more usually what's done is to just put up with it until the pads and rim surface wears.

Salamandrine 

Yep, stick with #1 ...

There is a 3rd way. Sand the toe in into the pad. There's enough meat on these. Oftentimes just a very shallow sanding of the back 1/3 of the pad or so is enough.

Salmon pads work great in the wet, but they are prone to squealing, they just are. Sorry salmon fans. You may need to use all the tricks in the book to quiet them, but I've never run into any that couldn't be quieted. You may want to take the brakes apart to clean and regrease the posts etc. Toe-in and sanding the rims are the main techniques mechanics used BITD. I realize people are afraid of sanding rims now. Oh well.

TenGrainBread 

Yep. I have heard people say use a file instead of sandpaper for shaping the pads so as not to get ultra-hard sandpaper grit on the pads and into the rims.

I have used red Scotchbrite to clean muck off rims, followed by a wipe with alcohol. I find that sometimes brake noise is due to grease or oil on the rim.

Charles Wahl

I don't know if your Dia-Compe cantilever shoe shafts and shoe-to-arm studs have the same diameters as those on Mafac (French) centerpulls (7 mm and 10 mm respectively) but if they do, then you can buy seating washers for them that are pre-toed (using grooves of unequal depth, as TenGrainBread recommends above -- from ReneHerseCycles.com (Jan Heine's outfit). But it seems to me that it would be simple enough to do this carefully with a rat-tail file.

My experience with Kool-Stop shoes like those pictured is that the rear of them (that is, the end that the rim surface meets first as it turns) have a bit of a "lip" curling toward the rim, which is intended to enforce a bit of toe-in by reducing the surface area of the rear of the shoe, and let the front end do the real work -- but that's based on shoes that have the threaded studs (like for a Weinmann centerpull, or the cantilever brakes designed for a similar shoe, and Kool-Stop provides them with sets of convex/concave washers to make toe-in easy.

I have just refurbished an ATB, replacing the original canti brakes (Shimano, I think, with shoes like yours) with a set of Tektro Oryx brakes that use the threaded-stud type of shoe. They seem to work really well, and came with (non-Kool-Stop) shoes that have the concave/convex washers. I found these to be very satisfactory.

Salamandrine 

Brain fart. These are Dia Compe 983. I think they may actually have adjustable toe-in. There was or may be a convex or concave washer at the back of the brake post attachment bolt. 981 had one. If you loosen it, you will be able to change the position of the pad - ie, toe it in. TRY THIS FIRST!

Loosen the bolt and see if pads will shift angle.

I adjusted 5 zillion of these BITD, but that was a long time ago now. Hard to keep them all straight.

The Golden Boy 

One thing Shimano really got right was the toe-in adjustment on the cantilever brakes-

Even after Dia Compe got a good system- the Shimano adjustment is better.

Sorry I can't be of substantive help...

JohnDThompson 

Those brakes actually have spherical washers where the pad posts attach. Those allow you to set toe-in by loosening the nut holding the post, re-positioning the pad for the toe-in, and then tightening the nut to hold it in place.

There are tools to facilitate setting toe-in; some people just use a piece of cardboard under the leading edge of the pad to set the angle. I just hold the pad in place while tightening. You can stick an Allen key into the socket to help keep the angle you want while tightening the nut.

Salamandrine 

Toe in method #4 , use the actual toe in adjustment that's built into the brakes.

Thanks for that confirmation. Sorry I missed it in my first post. Forgot that these 2nd generation DC brakes had toe in adjustment.

IMO it will be easier to use the adjustment feature if the mechanism is taken apart and cleaned, and a light film of grease put on everything. I bet it's all a bit corroded and sticky now.

steelbikeguy

this reminds me a lot of my SunTour XCD canti's... the bike was new, the rims were new, and the Koolstop pads were new! Beautiful, but all of that newness led to lots of noise!

Eventually, the rims got roughened up from riding in the rain, so the pads didn't stick to them so much.
Also, the pad material got harder and less sticky as they aged. Getting filthy from riding in the rain probably helped too.

Other than this sort of break-in period, I do like to file a bit of material off of the back half of the pads. This is especially useful for brakes with no toe-in adjustment.

Steve in Peoria

mechanicmatt

To add to this an old trick to learn toe in was to put a rubber band around the back tail end of the pad and adjust it flat against the rim with the rubber band on. Take the rubber band off and you should have proper toe in.

Glennfordx4

I myself have used a old credit card cut into strips to set toe in canti brakes & it worked good enough that I kept them in my bike tool box.

Glenn

madpogue 

Oh, you're supposed to use an old one? Oops....


(But yes, credit card thickness seems to be about right. Who doesn't have an old Blockbuster Video rental card in a drawer somwhere?)

Salamandrine 

With those big soft salmon pads on vintage cantilevers, I'd be inclined to go a little more aggressive with the toe in. A credit card thickness is only ~ .030". First guess would be around a penny thick.

I've always done it by eye, and used as much as needed and not more. On these vintage calipers, inserting an object of known thickness and tightening the pad down flat rarely works as well as it can with modern pads. The pads will tend to shift around as they are tightened.

Toe in alone is not usually enough.

canklecat

If those are Kool Stop Eagle 2 (Eagle Claw) pads, they're easy to toe-in. Just mash the pad flat against the rim, align, and crank the locking bolt. Done. The wedge tip aligns the toe-in.

If there's any squealing just bomb down a hill while riding the brake -- the slight wear and glazing will stop the squealing. I do that during/after wet rides due to rain or puddles. It'll squeal briefly until I've braked a couple of times.

As someone else noted it's mostly due to a resonance/vibration quirk and some setups will squeal very little, if at all. When I switched my Univega from the original plain aluminum low profile single wall rims to slightly higher profile double wall rims, there was little or no squealing. It just coincidentally changed the resonance that caused some squealing with the original wheels.

The tricky part with most canti brakes is setting the distance and angle so the pads are square against the rim when closed. It'll look way off when the brakes are open, but that's normal. I usually wrap some cord or bungee around the brake levers to hold 'em partially closed while making those adjustments.

With other pads that don't have the wedge/plow tip of some Kool Stops, ditto the tricks for creating a little gap: zip tie, rubber band, credit card, penny, whatever. I use zip ties.

robertj298 

Thanks guys

gugie 

That's my method. The one problem with it is the stigma of low price.

63rickert

Last ditch when toe-in does not work——reverse the process. Do toe-out instead. Can’t explain that but it has worked and the brakes function just as well.