brake pads
 

how do you achieve the toe-ins and why do you want to have that instead of a pad perpedicular to the brake surface?

By toeing in your brakes you can reduce the oscillation that cause audible squealing.

i have ultegra 6700 brakeset. is there a way to adjust toe on the pads?

are there a set of concave,& convex washers on the brake pad posts?

Toe-in was used for older brake systems specifically cantileves, on modern brakes, like V's and dual pivot calipers like the 6700's there isn't really any need,

Having run 6700's for about 10000 Km, have never used toe-in, and never seen the need for it.

Haven't found a way to quietly stop without toe-in with Tektro V-brake on Velocity Aeroheat rim (front wheel) - have tried a variety of Kool-Stop and Avid pads.

The idea is that when the brake pads grab the rim, they are pulled forwards, twisting the brake pads so that they are toe-out. This reduces brake friction, letting the pads twist back slightly etc etc. This causes oscillations of audible frequencies, leading to brake squeal. Setting the pads toe-in slightly prevents this by using the brake forces to pull the pads straight, increasing brake force.

To set the toe-in, there should be a set of concave/convex washers on a threaded brake pad, which allows it to be rotated slightly before tightening. Smooth studs as found on cantilevers should have a similar adjustment in the fixing bolt.

You toe in brake shoes for the same reason that car mechanics toe in front wheels. They move slightly under load and you're compensating.

When you apply a brake, the motion of the rim pushes the shoe forward. Since the point of attachment is out from the rim that causes the shoe and brake arm to twist bringing the toe out, and the heel in. This can cause vibration, or the classic new-brake squeal or, in some cases, the extreme pulsing that front brakes sometimes exhibit. With increased pressure the shoes are forced flat, so this is mostly a problem in mid range brake use, like when managing speed on descents.

The right amount of toe-in depends on the rigidity of the brake system. Over time the shoe will naturally wear into a slight toe-in pattern, so what you do is only the starting place. I usually use a dime under the tail end to get a good approximation, and rarely have to change it.

One way to see if you have it right is to apply the brake moderately and push the bike against it. Ideally you'll see the shoe rotate to a flat contact with the rim.

On caliper brakes I wrap a disassembled matchbook cover over the tire and under the rear facing edge of the brake pad on each side. I squeeze the brake lever and hold it firmly then loosen the two brake pads and re-tighten them.

So I get this right, on the front rim, I would have the front-most part of the brake pad slightly closer to the rim than the rearward part of the pad?

Also, while we're on the subject, why exactly would SwisStop pads cost so much more than Bontrager pads (for carbon)? I need to replace the pads and I do not understand why there is that kind of cost difference? I am unworthy, but I have a set of Bontrager XXX Lite rims which I got at a great price.