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  1. #1
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    need replacement for Promax 85mm mini-V

    I have a Schwinn Super Sport flat-bar road bike.

    After 1600 miles, the brakes feel mushy. Probably housing/cables need to be replaced.

    It comes with Promax 85mm mini-V (V brake). So, I had this idea to replace the brakes with Avid SD7 (100mm, $19 per). One problem..they don't fit!! Or, can I replace the stud that screws into the boss?

    Or, can someone recommend a good replacement mini-V?

    I did some research, & the Tektro RX5 have good reviews.

    http://www.bikeforums.net/archive/in.../t-417670.html

    Would the Tektro 926A be a candidate?

    http://www.jensonusa.com/store/produ...ni+L-Pull.aspx

    Another option is just to keep the Promax 85mm.

    I ended up getting the Alligator Super Fortress cable kit (stainless mesh reinforced). I figure I should upgrade the brakes for this fancy cable (i.e., go with a Tektro rather than keep the Promax)

  2. #2
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    Quote Originally Posted by SilverStar
    How is it that the replacement brakes don't fit? All of those studs are the same, as far as I know...in other words, mini-Vs aren't designed to go on special studs.
    The replacement brake (Avid SD7) is different:

    1) less recess (to go over the stud's "mound")
    1/8" vs 3/16"

    2) the pin for the spring is "raised at the base"

    as the result (due to 1), the arm won't seat flush to the boss.

    vbrake..jpg
    Last edited by chimpanzee; 05-05-10 at 05:00 PM.

  3. #3
    Death fork? Naaaah!! top506's Avatar
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    Quote Originally Posted by chimpanzee View Post
    Would the Tektro 926A be a candidate?

    http://www.jensonusa.com/store/produ...ni+L-Pull.aspx
    The Tektros work well for me on a Miyata Triplecross.
    Top
    You know it's going to be a good day when the stem and seatpost come right out.

  4. #4
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    Quote Originally Posted by chimpanzee View Post
    The replacement brake (Avid SD7) is different:

    1) less recess (to go over the stud's "mound")
    1/8" vs 3/16"

    2) the pin for the spring is "raised at the base"

    as the result (due to 1), the arm won't seat flush to the boss.

    vbrake..jpg
    I went to 4 bike shops, & they told me the gap wouldn't affect operation. However, the pin for the spring would seem be a weak point (there would be leverage at the end of the tip, where it seats into the boss).

    Suppose I ground down the brake boss stud from 3/16" to 1/8", so the Avid arms would fit flush to the boss. Would I weaken the stud? A bike shop claimed it would.

  5. #5
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    Quote Originally Posted by chimpanzee View Post
    I went to 4 bike shops, & they told me the gap wouldn't affect operation. However, the pin for the spring would seem be a weak point (there would be leverage at the end of the tip, where it seats into the boss).

    Suppose I ground down the brake boss stud from 3/16" to 1/8", so the Avid arms would fit flush to the boss. Would I weaken the stud? A bike shop claimed it would.
    when you remove metal it weakens it, especially in a critical place like a brake stud

  6. #6
    Senior member Dan Burkhart's Avatar
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    Quote Originally Posted by chimpanzee View Post
    I went to 4 bike shops, & they told me the gap wouldn't affect operation. However, the pin for the spring would seem be a weak point (there would be leverage at the end of the tip, where it seats into the boss).

    Suppose I ground down the brake boss stud from 3/16" to 1/8", so the Avid arms would fit flush to the boss. Would I weaken the stud? A bike shop claimed it would.
    That gap is not unusual. Any Tektro Oryx brakes, ( sometimes branded as Cane Creek) will have that gap, even when supplied as original equipment on a new bike.
    I would not grind anything, just mount the brake and be happy.

  7. #7
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    Quote Originally Posted by Dan Burkhart View Post
    That gap is not unusual. Any Tektro Oryx brakes, ( sometimes branded as Cane Creek) will have that gap, even when supplied as original equipment on a new bike.
    I would not grind anything, just mount the brake and be happy.
    +1. The brakes will work, it just might look a little different then what it was before.. All modern cantilever-style (centre-pull cantilever style, Vs and Mini Vs) all fit on the same standard studs and spring holes.

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