We're going to move this pad up, and I'm going to go ahead and take it off of there and show you how this system works on most V-brakes. This system has a stack of washers on either side of the brake arm. The brake arm is just a flat tab with a slot in it, and the brake arm for this pad can slide up and down in that slot, but the slot alone doesn't allow it to move this way, or this way, to pivot.
So that's what these washers do. On either side of the brake arm you're going to have one that's concave, and one that's convex, and they nest in each other. You can see that the one on the other side of the brake arm, convex ones are both the same but the concave ones are of two different thicknesses. That's how you adjust pad offset on this type of a brake.
If you wanted to have the brake arms more vertical, you could interchange these to the two concave ones, so that then this stack was here, and then that made the pad closer to the arm, and then the arm of course have to be more vertical when the pad is against the rim. If you have it too close, when you pull the brake, if the distance between the noodle and this arm is too short, you can bottom out the brake before the pads are against the rim.
So going with the stock set up with the thicker concave washer to the inside is a good idea, in this case. And there is one other flat washer that we're going to put on top, flat washer is what keeps the nut from throwing off the position of the concave and convex washers when you tighten it. Go ahead and reconnect the brake, and so we got the pad on there, and it's loose, pull the brake. Pad offset is set, that's the in and out, that's we did with the spacers.
Pad like this, all of the dimensions are loose at the same time, all of the twist, the toe in, the angle to the rim, so it's moving loosely until we pull the lever and hold it tight against the rim, and then loosen this up to make sure it's kind of jiggled in place. You made sure that the curvature matches the rim's curvature. We made sure the height is right that the pad is exactly flat against the rim, snugging it up a bit, and then once we get to where it's held and placed pretty well, then we release the brake and hold it with our hands, because just the friction against the rim would not be enough to allow us to hold in place while we really tighten down on it.
Now we're happy with the way this pad is hitting, and the other pad is fine too. But now we still have the problem that we've had all along, which is where this side is rubbing and that side is not. So the balance between these springs is off. Now on a V-brake like this, this is the normal spring system. It's a vertical spring. To center this, either you need more tension on this side, or less on that side, or a combination, in order that this is going to pull out more.
So for the time being we'll go with more on this side, turn this a little bit. As we turn it, this brake will start to come out. It's now returning very nicely away from the rim, and there is a low spot in the rim, and at that low spot the tire is hitting that brake pad. So we actually have our pad too high. I'm going to pull the brake tight, so that it stays basically in position, and then I can just make a very small adjustment. I'm going to scoot that pad down here, and make sure the curvature is matching.
Snug this, so it stays in place. We'll spin in again and see; now we're not hitting the tire, okay, so we're happy with that. Now we're going to hold it, and do the final tightening. Nothing is rubbing; the traction is good on both sides. That's a good brake adjustment.
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