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StopMeansStop
10-27-2011, 10:59 PM
My front brake pads are not equidistant from the rim. One pad is extremely close to the rim and buzzes all the time. My LBS seems unable or unwilling to do what it takes to correct this. I'd like to figure out how to fix this myself. Any suggestion on where I can take this and get me some education?

Thanks

Dirt
10-27-2011, 11:44 PM
Phoenix bikes shop night might be a good place to start. http://phoenixbikes.org/

Dirt
10-28-2011, 04:52 AM
Leonard Zinn has written a few good books on bicycle repair. Google will find them and they're available locally. Rock on, sir.

DismalScientist
10-28-2011, 08:51 AM
First step: Is your wheeled centered? If not, undo quick release, center wheel and tighten QR.
Second step: What kind of brakes do you have? Some brakes may require moving the brake relative to the frame. Others require adjusting the relative strength of the springs.
Third step: Denial: yell obscenities at the offending component.
Fourth step: Acceptance. Rubbing brake pads mean getting more exercise. More exercise means consuming more beer.

baiskeli
10-28-2011, 08:55 AM
My front brake pads are not equidistant from the rim. One pad is extremely close to the rim and buzzes all the time. My LBS seems unable or unwilling to do what it takes to correct this. I'd like to figure out how to fix this myself. Any suggestion on where I can take this and get me some education?

Thanks

We need to know what kind of brakes. Can you pick them out from here? There are pictures: http://en.wikipedia.org/wiki/Bicycle_brake#Types_of_rim_brakes

Joe Chapline
10-28-2011, 09:22 AM
Third step: Denial: yell obscenities at the offending component.

I had a friend who used to say, "You have to call it by its right name."

StopMeansStop
10-28-2011, 09:33 AM
Wheel is centered. Linky goes to brake

http://www.jensonusa.com/store/product/BR307B00-Tektro+Cr720+Cantilever+Brake.aspx

americancyclo
10-28-2011, 09:35 AM
sometimes the tightening of the screw near the spring of the pad that is rubbing will help it pull away from the rim.

paulg
10-28-2011, 09:44 AM
Try this: The two small allen head bolts that screw up into the arms of the brake calipers (they are almost vertical) should be for making adjustments to the brake return spring tension on each side.

On the side that has the pad touching the rim tighten that allen head bolt to increase the return spring tension in the caliper. You you should notice the pad moving away from the rim as you tighten the bolt. squeezing the brake lever after each adjustment helps the brakes move to their new position. Keep doing this until the pads are equal distance from the rim on both sides.

Tightening the bolts will increase the tension but you can also loosen them if one bolt has run out of adjustment. Wherase tightening the bolts moves the pad away from the rim loosening the bolt will move the pad close as the tension on the other caliper pulls it over.

Don't be afraid of making these adjustments, you can't really break anything. Just be gentle and don't over tighten the bolts. Play with them until you get to where they need to be.

If this does solve the problem then I'm surprised your LBS didn't know how to do it.

Good luck and let us know how you get on.

baiskeli
10-28-2011, 09:55 AM
Wheel is centered. Linky goes to brake

http://www.jensonusa.com/store/product/BR307B00-Tektro+Cr720+Cantilever+Brake.aspx

Ah, cantilever brakes.

The solution is to buy a new bike. ;)

Failing that, does the cable that pulls them together (the straddle wire) connect with a bolt to the main cable, or is it loose and wrapped around a little metal yoke attached to the main cable? If it is attached by a bolt, adjusting the position of that bolt may do the trick. It doesn't show the straddle wire in the picture, but in a review on that site, someone writes "straddlewire can be set not to slide on the clamp." So it sounds like it can be done, maybe even if it uses a yoke.

Or does it look like this?

http://www.treefortbikes.com/images/raw/TFB10_BR7462-2.jpg

In this picture, the bolt on the right brake lets you adjust the length of the straddle wire and therefore the total space from rim to pads to work with. The top bolt adjusts brake tension, but that will also affect the spacing. The two lower ones hold the straddle wire in the place where you get the right space on each side. You'd probably need to keep working on all these bolts a few times to get it just right. Also, a pivot bolt may need to be loosened to tightened to equalize the tension when the brakes are resting - maybe one is simply stuck too tight. And the distance the pad sticks out from the brake arm may also be adjustable. To get the adjustment right, you may need to hold the other side of a bolt with a wrench, since the cable or arm may move as you turn it.

Best to adjust and then ride a little and squeeze the brakes, then adjust again if necessary, since they sometimes kind of settle into a new spot after use.

Hope I'm not telling you something you don't already know.

elcee
10-31-2011, 06:39 PM
Cantilevers ... what can I say? Too many degrees of freedom, meaning that it's all too easy to mess things up.

It helps to have another set of hands to hold the brake arms or pads in position while you tighten the bolts.

Believe me, when you get those cantilevers adjusted right, you'll feel such a warm glow of satisfaction that you'll want to do it all over again.