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  1. #1
    vasbear
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    "V" Brake Pad Centering

    Old guy herewith single speed crank and coaster brake mentality. I have A Schwinn Avenue Hybrid with V or linear brakes (semantics I guess), and one of the rear [pads drags. I have removed wheel and it is straight, moved springs to upper limit holes, loosened the cable adjust barrel fully out and then released 5 MM pinch bolt. I grip the pad arms together so the pads almost contact the rim (pads are straight on rim), pull cable up and tighten pinch bolt and then turn barrel adjuster full in but, now I cannot contact rim with pad even if I turn the set screws fully in. I definitely need help, and yes I have visited Sheldon Brown's site as well as You Tube tutorials and still I am lost.

    As they down South, HEP!

  2. #2
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    Not sure I understand the question, so I'll cover both.

    Brake centering in the open position, is controlled via the small spring tension adjusting screws down near the pivots. They change the return spring tension and you want to achieve balance. Loosening one side or tightening the other is equal, so don't take either to the end, but use them together for best balance. BTW- pivot bolt friction affects balance so put a drop of light oil on each pivot. so you know the friction is equal on both arms.

    Brake closing is via the cable. It's self centering because once one shoe touches that arm stops and the other continues to move until both shoes are engaged. make sure the shoes are correctly positioned on the rim then pinch both arms together at the top to check that all is working. Then it's a matter of cable length. If the lever doesn't have enough throw to close the brake, the cable needs to be shortened via the adjusting barrel. If you run out of travel, than you need to pull the wire through the pinch bolt some more.

    Before adjusting at the pinch bolt, return the barrel all the way down so you have the ability to tighten more later. Loosen the pinch bolt, and while squeezing both arms together t the top pull the wire through until tight, then tighten the pinch bolt slightly and see if the arms open roughly the right amount. You may also tighten the bolt a bit more and give a gentle squeeze of the lever to check if it's about right overall, then you can tighten the pinch bolt the rest of the way to lock it in place. Now if you need to tighten a bit more use the adjuster.
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  3. #3
    vasbear
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    Okay understand and will try your suggestions. One more question or maybe two, is there any set start position for the pad set screws (fully in,fully out or mid-way). And if one pad is dragging will releasing tension on opposite pad set screw shift tension to the dragging brake spring?

  4. #4
    coprolite fietsbob's Avatar
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    Adding a bit of bend to the weak return spring, increases its force.
    they are not tempered.
    you might get the screw to give you that , screwing it in more.

  5. #5
    Junior Mint jimn's Avatar
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    I may be misunderstanding your question, but when you say

    now I cannot contact rim with pad even if I turn the set screws fully in.
    it makes me wonder if you have somehow got a pair of normal (short-pull) brake levers for your linear (long-pull) brakes. Some brake levers I have seen even have two positions for the cable end - one for normal and one for linear pull.

    Just another thing to check if you haven't already.

  6. #6
    vasbear
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    I will try all of your suggestions tomorrow and report back. But again is there a staring point for the adjust screws, should they be out a great deal before staring the cable adjustment so that if the pads drag after that procedure there is room to screw them in.

    The Old Confused Guy

  7. #7
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    Quote Originally Posted by VABEAR View Post
    Okay understand and will try your suggestions. One more question or maybe two, is there any set start position for the pad set screws (fully in,fully out or mid-way). And if one pad is dragging will releasing tension on opposite pad set screw shift tension to the dragging brake spring?
    There's no absolute starting point, but all things being equal, the starting point might be half way in for both, so you have the most room for adjustment. Following that logic, if you need to increase the tension on the side where the screw is already in most of the way, then you should loosen the opposite screw.

    That answered the second question, tightening one spring has the same effect as loosening the opposite. Imagine a seasaw with the kid at one end heavier than the one at the other. To get the seesaw level, you can push down the light kid's end, or lift the heavy kid's. Likewise for centering V-brakes.
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    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

  8. #8
    vasbear
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    V brake Centering

    Got it, off top the races

  9. #9
    vasbear
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    V brake pad centering complete, thanks to all for your advice. Now I can do" "V Brakes, Rear Coaster Brake cones and single speed crank bottom brackets, what will be my next challenge?

  10. #10
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    Welcome to the bike tech lottery. Ride the bike and something will happen, then you'll learn to deal with it. Odds are it'll be something gear cable related, but you never know what's around the corner until you turn it.
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    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

    “One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

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