Ritchey OCR Wheels

Discussion in 'Cycling Equipment' started by Greg Sackett, Mar 4, 2003.

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  1. Greg Sackett

    Greg Sackett Guest

    I recently purchased a Jamis Aurora for my wife. While replacing a few components, namely the
    brakes, I noticed that the rear wheel didn't appear centered. So I checked it with both my truing
    stand as well as my dishing tool, and sure enough, it is several mm (like 5 or so) off center (rim
    closer to drive side).

    This wheel is a Ritchey OCR Comp 700 coupled with a Ritchey ZER System hub (8/9 speed). Because this
    is an off center rim and hub, was the wheel built incorrectly? To fix the problem do I need to
    completely rebuild the wheel with shorter spokes on the non-drive side?

    Suggestions?

    Greg
     
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  2. David Ornee

    David Ornee Guest

    "Greg Sackett" <[email protected]> wrote in message
    news:[email protected]...
    > I recently purchased a Jamis Aurora for my wife. While replacing a few components, namely the
    > brakes, I noticed that the rear wheel didn't appear centered. So I checked it with both my truing
    > stand as well as my dishing tool, and sure enough, it is several mm (like 5 or so) off center (rim
    > closer to drive side).
    >
    > This wheel is a Ritchey OCR Comp 700 coupled with a Ritchey ZER System hub (8/9 speed). Because
    > this is an off center rim and hub, was the wheel built incorrectly? To fix the problem do I need
    > to completely rebuild the wheel with shorter spokes on the non-drive side?
    >
    > Suggestions?
    >
    > Greg

    Greg,

    The OCR aspect of the rim has nothing to do with correct centering. OCR is a design that allows the
    drive spokes to have a greater spoke support angle and therefore making the side to side spoke
    tension closer to even. If the correct spoke lengths were selected for the build you should be able
    to re-dish the wheel to make it properly centered without changing any spokes. You will be able to
    tell if you look at the spoke thread engagement at the back end of the nipples. When you are done
    re-centering, don't forget to stress relieve the spokes again. I don't want to insult your
    intelligence, but make sure you are using the dishing tool correctly, with the gauge resting on the
    locknut and the ends resting on the rim. I have seen cases of the gauge resting on the axle end and
    others where one end was touching a spoke. David Ornee, Western Springs, IL
     
  3. Jim Edgar

    Jim Edgar Guest

    Greg Sackett at [email protected] wrote on 3/4/03 6:32 AM:

    > I recently purchased a Jamis Aurora for my wife. While replacing a few components, namely the
    > brakes, I noticed that the rear wheel didn't appear centered. So I checked it with both my truing
    > stand as well as my dishing tool, and sure enough, it is several mm (like 5 or so) off center (rim
    > closer to drive side).
    >
    > This wheel is a Ritchey OCR Comp 700 coupled with a Ritchey ZER System hub (8/9 speed). Because
    > this is an off center rim and hub, was the wheel built incorrectly? To fix the problem do I need
    > to completely rebuild the wheel with shorter spokes on the non-drive side?

    The OCR wheel I have uses the same size spokes for drive and n/d sides. Tension is virtually
    identical on both sides. The hub needs to have the correct orientation with respect to the OC rim.
    Wheel should be centered.

    hope that helps,

    -- Jim
     
  4. "Greg Sackett" <[email protected]> wrote in message
    news:[email protected]...
    > I recently purchased a Jamis Aurora for my wife. While replacing a few components, namely the
    > brakes, I noticed that the rear wheel didn't appear centered. So I checked it with both my truing
    > stand as well as my dishing tool, and sure enough, it is several mm (like 5 or so) off center (rim
    > closer to drive side).
    >
    > This wheel is a Ritchey OCR Comp 700 coupled with a Ritchey ZER System hub (8/9 speed). Because
    > this is an off center rim and hub, was the wheel built incorrectly? To fix the problem do I need
    > to completely rebuild the wheel with shorter spokes on the non-drive side?
    >
    > Suggestions?
    >
    > Greg

    Unfortunately, it's not that unusual for a bike to have the wheel dish off out of the box. As others
    have said, make sure you're using the dishing tool properly, with the center gauge/bolt on the
    locknut, not the axle end, and the ends resting on the outer edges of the rim. Let the dishing tool
    be your benchmark, as it doubles the error and gives you the most accuracy. Whatever the gap is with
    the tool, the actual offset is half that much. To fix it, just back off all the spokes a bit on the
    side the rim's offset towards and tighten the other side by the same amount. Once it's close, you
    can do only one side's spokes to get the rim centered.

    Probably a good thing, actually, as OEM Ritchey wheels are known for inadequate build quality. A bit
    of attention would likely benefit both wheels and pay dividends in wheel life.

    SB SB
     
  5. Andymorris

    Andymorris Guest

    Steve Blankenship wrote:

    > Let the dishing tool be your benchmark, as it doubles the error and gives you the most accuracy.
    > Whatever the gap is with the tool, the actual offset is half that much.

    I've always thought of it as 4 times. Twice as you have described and another twice because your
    measuring the difference between the locknut to rim distances.

    So if you have a feel for how much a 1/4 turn moves a rim when your trueing, it will remove an out
    of dish measurment of 4 times that.

    --
    Andy Morris

    AndyAtJinkasDotFreeserve.Co.UK

    Love this: Put an end to Outlook Express's messy quotes
    http://home.in.tum.de/~jain/software/oe-quotefix/
     
  6. A Muzi

    A Muzi Guest

    "Greg Sackett" <[email protected]> wrote in message
    news:[email protected]...
    > I recently purchased a Jamis Aurora for my wife. While replacing a few components, namely the
    > brakes, I noticed that the rear wheel didn't appear centered. So I checked it with both my truing
    > stand as well as my dishing tool, and sure enough, it is several mm (like 5 or so) off center (rim
    > closer to drive side).
    >
    > This wheel is a Ritchey OCR Comp 700 coupled with a Ritchey ZER System hub (8/9 speed). Because
    > this is an off center rim and hub, was the wheel built incorrectly? To fix the problem do I need
    > to completely rebuild the wheel with shorter spokes on the non-drive side?

    Disregard any marketing-speak and just center the rim over the locknuts as with all bicycle wheels.

    When you drop the wheel into the bicycle or a truing stand and note the place the rim falls,
    flipping the wheel over should exactly duplicate the rim's position. ( a wheel cenetring, aka
    "dishing", tool shows this more conveniently).

    The claimed advantage of modern asymmteric rims is spoke tension that's less differentiated from
    left to right. That effect is not significant to spoke length. Overall this design is a good thing.
    Ritchey's is a good design. But no improvement to rim design covers for sloppy building, as you
    discovered.

    You should evaluate the wheel's overall tension and either slack one side or, more likley, tighten
    one side, such that the rim is centered over the locknuts. If the nipples "klink" when you turn
    them, detension the wheel completely and lubricate the nipples. This will actually save time and
    frustration. As you bring it back to tension, centered, ensure it is round and in one plane, stress
    relieve the spokes and you're done!
    --
    Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
     
  7. greg-<< So I checked it with both my truing stand as well as my dishing tool, and sure enough, it is
    several mm (like 5 or so) off center (rim closer to drive side). << Because this is an off center
    rim and hub, was the wheel built incorrectly

    << To fix the problem do I need to completely rebuild the wheel with shorter spokes on the
    non-drive side?

    N-loosen the tension, dish, round, true on the way to proper tension and stress relieve as
    well..Many of these wheels are built poorly, along with just about every wheel I see that comes
    outta a box, or on a new bike.

    But giving these, as well as many wheels, some attention when new, can make for a good,
    reliable wheelset.

    Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
    (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"
     
  8. Andy-<< Disregard any marketing-speak and just center the rim over the locknuts as with all
    bicycle wheels.

    Ya suppose the offset rear rim was built backwards?

    Spoke holes should appear on the left side of the rim, with the cogset on the right, when looking at
    the wheel.

    Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
    (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"
     
  9. A Muzi

    A Muzi Guest

    > Andy-<< Disregard any marketing-speak and just center the rim over the locknuts as with all
    > bicycle wheels.

    "Qui si parla Campagnolo" <[email protected]> wrote in message
    news:[email protected]...
    > Ya suppose the offset rear rim was built backwards? Spoke holes should appear on the left side of
    > the rim, with the cogset on
    the
    > right, when looking at the wheel.

    Maybe a picture would be helpful. http://www.yellowjersey.org/velrim.html (The one at the top) There
    should be more rim to the right of the spokes than to the left of them.

    --
    Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
     
  10. Greg Sackett

    Greg Sackett Guest

    > Ya suppose the offset rear rim was built backwards?

    Pete,

    That was the first thing I thought of, but the orientation was fine. I took your advice and
    tightened all the spokes (3 or 4 times more on the non-drive side) and it centered up without
    any problems.

    I appreciate everyone's advice on the topic.

    Many thanks!

    Greg
     
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