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  1. #1
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    Ultegra Open Pro spoke question

    I have a pair of Open Pros that were taco'd in an accident with a car, I want to buy new open pro rims and spokes and build up some new wheels with the old Ultegra hubs.
    I bought the wheels new and they were already built. I have removed some spokes from the damaged wheels and measured them and they are different sizes to what the online spoke length calculators recommend.
    Can someone please tell if I am measuring from the correct part of the spoke?
    The spoke sizes I have when measuring from here are front 294mm, rear left 293 and rear right 291mm.
    Online calculators recommend Front 296mm, rear left 296mm and rear right 294mm.
    What size should I get?
    Open Pro rims on Ultegra 6600 hubs.
    Thanks


  2. #2
    Fred-ish rogerstg's Avatar
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    Not enough info. Number of spokes? lacing pattern?

  3. #3
    Senior Member mrrabbit's Avatar
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    ERD = 602 (Screwdriver flat of nipple)
    32H
    3X

    295.42 @ 295.00

    294.63 @ 294.00
    292.86 @ 292.00

    Will result after final tension and dish with spokes coming to just a hair under the screwdriver flat of standard nipples.

    =8-)

    The calculators you are using are aiming for the top of the nipple - that's why you are seeing longer lengths.

    http://www.mrrabbit.net/wheelsbyflemingapplications.php

    Is where mine is...grab the spreadsheet after scrolling part way down...

    =8-)
    4000+ wheels built since 1984...

    Disclaimer:

    1. I do not claim to be an expert in bicycle mechanics despite my experience.
    2. I like anyone will comment in other areas.
    3. I do not own the preexisting concepts of DISH and ERD.
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    Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life

  4. #4
    LET'S ROLL 1nterceptor's Avatar
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    These folks will send you the correct length after telling
    them what hub and rim you'll be using. They only sell
    double butted Wheelsmith spokes.

    http://peterwhitecycles.com/spokes.asp

    Model
    Weight of 32, 262mm spokes w/o nipples
    Price per spoke with nipples
    Wheelsmith DB14, 14-16 gauge
    172 grams
    $1.05 each
    Wheelsmith DB14, 14-16 gauge (black)
    172 grams
    $1.36 each
    Wheelsmith XL14, 14-17 gauge
    137 grams
    $1.30 each
    Wheelsmith DH13, 13-14 gauge
    220 grams
    $1.25 each

  5. #5
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    Thank you mrrabbit that spreadsheet is awesome. Must have taken a lot of time. I feel confident in buying the same size spokes that were in my original wheels.

  6. #6
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    Yes, you measured correctly from the inside of the elbow (not on-center) to the end.

    IMO an actual built wheel trumps a calculated spoke length. Since you're using the same rims, measure the spokes as per your picture, and adjust if you wish according to how high the spokes reach into the nipples. Ideal is between the bottom of the screwdriver slot, and the you of the nipple, so add or subtract from the existing spokes to achieve that.
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    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

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  7. #7
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    If they are not kinked you can reuse the spokes. Make note of which way they were installed and use that on the new rims.

  8. #8
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    I was not sure if I could re-use them or not. There are some on the rear that are bent from where the car bumper hit me. The rear wheel is really bent, but I think I could use a lot of the spokes from the front wheel.

  9. #9
    Gear Combo Guru Chris_W's Avatar
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    Spokes can handle bending, it's just kinking that they don't like. I expect you can re-use most of your spokes.

  10. #10
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    You have to bend them to lace a wheel. A kink on the other hand is a stress riser and the point where a spoke will break.

  11. #11
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    If a rim is really bent in an accident, doesn't that put a lot of stress on the spokes, pulling them to one side? Making them weaker?

  12. #12
    Senior Member mrrabbit's Avatar
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    Quote Originally Posted by rustybucket View Post
    If a rim is really bent in an accident, doesn't that put a lot of stress on the spokes, pulling them to one side? Making them weaker?
    Spokes tension-wise are rated way beyond what most rims and hubs can handle. It's excessive flex at a given point allowed due to under tensioning, nasty single point kinking, and nasty cutting scrapes that typically do 'em in.

    I'd worry more about your rim in this case...it's a very lightweight racing clincher to begin with. Drop by a shop and get a second opinion if you are concerned, and/or post a pic here.

    =8-)
    4000+ wheels built since 1984...

    Disclaimer:

    1. I do not claim to be an expert in bicycle mechanics despite my experience.
    2. I like anyone will comment in other areas.
    3. I do not own the preexisting concepts of DISH and ERD.
    4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
    5. My all time favorite book is:

    Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life

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