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Cinelli fully-sloping crowns- Mr. Brandt?

Started by Thomas Hood · · Last activity · 33 posts · 3,696 views

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Cycling Equipment
Published
1 June 2003
Last activity
4 June 2003
Original author
Thomas Hood
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33
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  1. Just curiousity but could you explain what you mean by "abrupt transition" and "feathered"?

    "Cinelli sloping crowns....are failure prone at the abrupt transition from fork blade to the
    internal lug of the crown that cannot be feathered to a gradual transition as an external lug can."

    By abrupt transition I assume you meant that internal lug looked like the LCO4 shown here:
    ceeway.comFork Crowns 2.htm
    I.e. the end of the lug is perpendicular to the blades and straight.

    However it would appear the Cinelli crown's end is not like this:
    ceeway.comFork Crowns.htm The Cinelli SCA, Everest C60, C61A, C63, Columbus MAX all seem
    to share this. Do these not have 'internally feathered' ends or have I misunderstood you?

    The reason I ask is that I have just aquired an almost new Mercian fillet-brazed reynolds 653 frame
    with said crown. Stunning craftmanship; the guy I bought it off had too much money to spend and had
    just 'upgraded' to a giant carbon fibre compact!?! I'm not complaining he sold it to me for £75
    including a record f/mech and titanium seatpost. However after reading your 'colostomy' incident
    story I'm a bit wary of that bit....

    TIA,

    Thomas Hood

  2. "Thomas Hood" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Just curiousity but could you explain what you mean by "abrupt transition" and "feathered"?

    "Cinelli sloping crowns....are failure prone at the abrupt transition from fork blade to the
    internal lug of the crown that cannot be feathered to a gradual transition as an external
    lug can."

    By abrupt transition I assume you meant that internal lug looked like the LCO4 shown here:
    ceeway.comFork Crowns 2.htm
    I.e. the end of the lug is perpendicular to the blades and straight.

    However it would appear the Cinelli crown's end is not like this:
    ceeway.comFork Crowns.htm The Cinelli SCA, Everest C60, C61A, C63, Columbus MAX all
    seem to share this. Do these not have 'internally feathered' ends or have I


    misunderstood

    Quoted message said:

    you?

    The reason I ask is that I have just aquired an almost new Mercian fillet-brazed reynolds 653
    frame with said crown. Stunning craftmanship;


    the

    Quoted message said:

    guy I bought it off had too much money to spend and had just 'upgraded' to


    a

    Quoted message said:

    giant carbon fibre compact!?! I'm not complaining he sold it to me for £75 including a record
    f/mech and titanium seatpost. However after reading


    your

    Quoted message said:

    'colostomy' incident story I'm a bit wary of that bit....

    Most Mercians I've seen, as most British bikes with that style crown, used a Canetti rather than the
    Cinelli crown. ( You may know them best from Raleigh Professionals, Raleigh Competitions and
    Holdsworth Pros) Canetti crowns are thinner across the top between the blade and column. Cinellis
    are more arched viewed from the front. Cinellis are "waisted" when viewed from above, Canettis are
    not, there being a flat face across the front and back. Canettis end more abruptly inside than the
    later Cinelli which is shaped such that there is more penetration in front and back than in the
    center of the blade.

    --
    Andrew Muzi yellowjersey.orgyellowjersey.org Open every day since 1 April 1971

  3. Thomas Hood said:

    Just curiousity but could you explain what you mean by "abrupt transition" and "feathered"?

    The fork crown that Cinelli among others made popular due to its aesthetic shape, is solid steel
    (not hollow) as most fork crowns previously were. Typically the steer tube and fork blades
    overlapped and had a band-like structure that enveloped all three tubes as we see on a Masi for
    instance. The detail of that crown had features that even without feathering the crown to a smooth
    transition, made it in effect the same, similar to the filigree on Singer lugs. These in effect make
    a soft transition.

    The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end abruptly
    (because no one can see this) and out of sight out of mind. However, fork blades fail in fatigue at
    this transition, breaking off after an insignificant life duration. As I said, I had tow of these
    failures and insisted on an external crown that was filed to have a zero thickness transition. This
    has worked for many more miles than any of my Cinelli forks survived.

    Quoted message said:

    "Cinelli sloping crowns....are failure prone at the abrupt transition from fork blade to the
    internal lug of the crown that cannot be feathered to a gradual transition as an external
    lug can."

    Quoted message said:

    By abrupt transition I assume you meant that internal lug looked like the LCO4 shown here:

    Quoted message said:

    ceeway.comFork Crowns 2.htm

    Quoted message said:

    I.e. the end of the lug is perpendicular to the blades and straight.

    Only LC19 has a reasonable shape, and crowns of this design were made for road bicycles. Fork blades
    are thinner and lighter than any of these other designs that shorten the fork blade and reach down
    to [censored] with a heavy steel crown. It's all fashion BS.

    Quoted message said:

    However it would appear the Cinelli crown's end is not like this:

    ceeway.comFork Crowns.htm

    Quoted message said:

    The Cinelli SCA, Everest C60, C61A, C63, Columbus MAX all seem to share this. Do these not have
    'internally feathered' ends or have I misunderstood you?

    Not at all. The SCA stops abruptly and that is where fork blades fail.

    Quoted message said:

    The reason I ask is that I have just acquired an almost new Mercian fillet-brazed Reynolds 653
    frame with said crown. Stunning craftsmanship; the guy I bought it off had too much money to spend
    and had just 'upgraded' to a giant carbon fibre compact!?! I'm not complaining he sold it to me
    for £75 including a record f/mech and titanium seatpost. However after reading your 'colostomy'
    incident story I'm a bit wary of that bit...

    Well, I don't know what you are planning to do with it. Most collectors items don't get a lot of
    miles and are specifically held for their beautiful workmanship.

    The colostomy incident was a seat post failure, not a fork problem.

    Jobst Brandt [email hidden] Palo Alto CA

  4. "A Muzi" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:

    "Thomas Hood" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Just curiousity but could you explain what you mean by "abrupt


    transition"

    Quoted message said:
    Quoted message said:

    and "feathered"?

    "Cinelli sloping crowns....are failure prone at the abrupt transition from fork blade to the
    internal lug of the crown that cannot be feathered to a gradual transition as an external
    lug can."

    By abrupt transition I assume you meant that internal lug looked


    like the

    Quoted message said:
    Quoted message said:

    LCO4 shown here: ceeway.comFork Crowns 2.htm
    I.e. the end of the lug is perpendicular to the blades and straight.

    However it would appear the Cinelli crown's end is not like this:
    ceeway.comFork Crowns.htm The Cinelli SCA, Everest C60, C61A, C63, Columbus MAX all
    seem to


    share

    Quoted message said:
    Quoted message said:

    this. Do these not have 'internally feathered' ends or have I


    misunderstood

    Quoted message said:

    you?

    The reason I ask is that I have just aquired an almost new Mercian fillet-brazed reynolds 653
    frame with said crown. Stunning


    craftmanship;

    Quoted message said:

    the

    Quoted message said:

    guy I bought it off had too much money to spend and had just


    'upgraded' to

    Quoted message said:

    a

    Quoted message said:

    giant carbon fibre compact!?! I'm not complaining he sold it to me


    for £75

    Quoted message said:
    Quoted message said:

    including a record f/mech and titanium seatpost. However after


    reading

    Quoted message said:

    your

    Quoted message said:

    'colostomy' incident story I'm a bit wary of that bit....

    Most Mercians I've seen, as most British bikes with that style crown,


    used a

    Quoted message said:

    Canetti rather than the Cinelli crown. ( You may know them best from


    Raleigh

    Quoted message said:

    Professionals, Raleigh Competitions and Holdsworth Pros) Canetti


    crowns are

    Quoted message said:

    thinner across the top between the blade and column. Cinellis are


    more

    Quoted message said:

    arched viewed from the front. Cinellis are "waisted" when viewed from above, Canettis are not,
    there being a flat face across the front and


    back.

    Quoted message said:

    Canettis end more abruptly inside than the later Cinelli which is


    shaped

    Quoted message said:

    such that there is more penetration in front and back than in the


    center of

    Quoted message said:

    the blade.

    Andrew, I was wondering if Jobst's problems weren't caused in part by over-cooking -- heating up a
    big internal lug and forcing brass through a small seam. I understand the whole stress-riser thing
    (and it certainly makes sense), but I used Cinelli full sloping crowns for years (and high mileage)
    and never had a problem -- even a fork that was involved in a wall impact that resulted in the usual
    kink in the down-tube but no damage to the fork. I recently broke a 25 year old set of forks with a
    Cinelli semi-sloping crown, but then I had to drive my roof-rack mounted bike into a too low garage
    to do it. -- Jay Beattie.

  5. Quoted message said:

    Most Mercians I've seen, as most British bikes with that style crown, used


    a

    Quoted message said:

    Canetti rather than the Cinelli crown. ( You may know them best from


    Raleigh

    Quoted message said:

    Professionals, Raleigh Competitions and Holdsworth Pros) Canetti crowns


    are

    Quoted message said:

    thinner across the top between the blade and column. Cinellis are more arched viewed from the
    front. Cinellis are "waisted" when viewed from above, Canettis are not, there being a flat face
    across the front and


    back.

    Quoted message said:

    Canettis end more abruptly inside than the later Cinelli which is shaped such that there is more
    penetration in front and back than in the center


    of

    Quoted message said:

    the blade.

    --
    Andrew Muzi yellowjersey.orgyellowjersey.org Open every day since 1 April 1971

    Well not this one. Its definitely a Cinelli :-) ...or should that be :-(

    Thomas Hood

  6. [email hidden] wrote in message news:<[email hidden]>...

    Quoted message said:


    The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end abruptly
    (because no one can see this) and out of sight out of mind. However, fork blades fail in fatigue
    at this transition, breaking off after an insignificant life duration. As I said, I had tow of
    these failures and insisted on an external crown that was filed to have a zero thickness
    transition. This has worked for many more miles than any of my Cinelli forks survived.

    How many miles constitute an "insignificant life duration"?

  7. K? Harper said:
    Quoted message said:

    The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end abruptly
    (because no one can see this) and out of sight out of mind. However, fork blades fail in fatigue
    at this transition, breaking off after an insignificant life duration. As I said, I had tow of
    these failures and insisted on an external crown that was filed to have a zero thickness
    transition. This has worked for many more miles than any of my Cinelli forks survived.

    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    Jobst Brandt [email hidden] Palo Alto CA

  8. [email hidden] wrote in message news:<[email hidden]>...

    Quoted message said:
    K? Harper said:
    Quoted message said:

    The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end
    abruptly (because no one can see this) and out of sight out of mind. However, fork blades fail
    in fatigue at this transition, breaking off after an insignificant life duration. As I said, I
    had tow of these failures and insisted on an external crown that was filed to have a zero
    thickness transition. This has worked for many more miles than any of my Cinelli forks
    survived.

    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    I'm interested in your observations on this, and I want to make sure that I've got your
    statement clear: is it your experience that a Cinelli fully sloping crown can, and often does,
    fail by breaking fork blades at or around 5000 miles? Did the ones you write of break at or near
    that mileage?

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't Cinelli
    be fending off lawsuits left and right, presumably with your testimony as Exhibit A on why these
    things are unreasonably hazardous?

    Now, of course, just because something exists in the marketplace is no real evidence at all of its
    safety, design wisdom, etc. That is obvious. But the Cinelli crown has been around a long time, a
    lot of frames have been built using it, and if these facts resulted in a disproportionately large
    number of breakages (and, presumably in many -- though not all -- cases, resulting injuries), then
    wouldn't the tort system/products liability law force Cinelli to acknowledge a design defect?

    I know that you don't like the crown, and I have no reason to debate the engineering basis for your
    dislike. In terms of the design's drawbacks, I have to assume you are correct.

    I'm just asking, is it as failure prone as you say (i.e., reasonable expectation that a reasonable
    number of these things won't last over 5000 miles)?

    Ken Harper

  9. "Scoochiro" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    [email hidden] wrote in message


    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:
    K? Harper said:

    > The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end
    > abruptly (because no one can see this) and out of sight out of mind. However, fork blades
    > fail in fatigue at this transition, breaking off after an insignificant life duration. As I
    > said, I had tow of these failures and insisted on an external crown that was filed to have a
    > zero thickness transition. This has worked for many more miles than any of my Cinelli forks
    > survived.

    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    I'm interested in your observations on this, and I want to make sure that I've got your statement
    clear: is it your experience that a Cinelli fully sloping crown can, and often does, fail by
    breaking fork blades at or around 5000 miles? Did the ones you write of break at or near that
    mileage?

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't Cinelli
    be fending off lawsuits left and right, presumably with your testimony as Exhibit A on why these
    things are unreasonably hazardous?

    Part of this could be that very many bikes never see 500 miles usage, let alone 5000.

    Tim.

    ---
    Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (grisoft.comgrisoft.com).
    Version: 6.0.487 / Virus Database: 286 - Release Date: 01/06/03

  10. "Scoochiro" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    [email hidden] wrote in message


    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:
    K? Harper said:

    > The Cinelli crown has fairly thick lug extensions that go inside


    the

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > fork blades and end abruptly (because no one can see this) and


    out of

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > sight out of mind. However, fork blades fail in fatigue at this transition, breaking off
    > after an insignificant life duration.


    As I

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > said, I had tow of these failures and insisted on an external


    crown

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > that was filed to have a zero thickness transition. This has


    worked

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > for many more miles than any of my Cinelli forks survived.

    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    I'm interested in your observations on this, and I want to make sure that I've got your statement
    clear: is it your experience that a Cinelli fully sloping crown can, and often does, fail by
    breaking fork blades at or around 5000 miles? Did the ones you write of break at or near that
    mileage?

    I got way more than that out of mine. The whole bike was trashed in a car accident, rebuilt as a
    commuter and then broke at the seat tube. The fork was alive until the end. It took the impact of
    the car accident, transmitted it into the down tube which in turn kinked. I probably had a good 20K
    on that bike. I think the fork may still be around somewhere.

    Quoted message said:

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't Cinelli
    be fending off lawsuits left and right, presumably with your testimony as Exhibit A on why these
    things are unreasonably hazardous?

    Most people who have Cinelli full-sloping crowns clean their bikes so often that they would notice a
    crack. I think a few of the De Rosas or Masis came with that crown -- or maybe it was the old
    Raleigh Pro. Anyway, I saw one somewhere in the early '70s and had to have it on my super-fine
    custom built frame. It was not spec'd on Huffys.

    Quoted message said:

    Now, of course, just because something exists in the marketplace is no real evidence at all of its
    safety, design wisdom, etc. That is obvious. But the Cinelli crown has been around a long time, a
    lot of frames have been built using it, and if these facts resulted in a disproportionately large
    number of breakages (and, presumably in many -- though not all -- cases, resulting injuries), then
    wouldn't the tort system/products liability law force Cinelli to acknowledge a design defect?

    Jobst has this Hulk thing going and breaks everything. For the usual schlub, the Cinelli full
    sloping crown is plenty safe -- although you did not hear that from me and cannot rely on anything
    that I say. It does have a built-in stress-riser, so it really is not the best design.

    Quoted message said:

    I'm just asking, is it as failure prone as you say (i.e., reasonable expectation that a reasonable
    number of these things won't last over 5000 miles)?

    Get with it man, this is the new age of disposable bicycles and components. Read your warranty (or,
    more accurately, your warranty disclaimer). -- Jay Beattie.

  11. They are Cinelli "style" crowns...

    Cinelli doesn't make them, and hasn't since the early 70s. Back then, the industry "copied" the look
    and many firms produced a look-a-like crown for all sorts of blades.

    Cinelli crowned forks graced Cinelli bicycles. Tens of thousands of forks, made to look similarly,
    are just that: copies. No need to worry about suits nor Cinelli's "place" in all this!

    e-RICHIE www.richardsachs.com

    [email hidden] (Scoochiro) wrote in message
    news:<[email hidden]>...

    Quoted message said:

    [email hidden] wrote in message
    news:<[email hidden]>...

    Quoted message said:
    K? Harper said:

    > The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end
    > abruptly (because no one can see this) and out of sight out of mind. However, fork blades
    > fail in fatigue at this transition, breaking off after an insignificant life duration. As I
    > said, I had tow of these failures and insisted on an external crown that was filed to have a
    > zero thickness transition. This has worked for many more miles than any of my Cinelli forks
    > survived.

    Quoted message said:
    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    I'm interested in your observations on this, and I want to make sure that I've got your statement
    clear: is it your experience that a Cinelli fully sloping crown can, and often does, fail by
    breaking fork blades at or around 5000 miles? Did the ones you write of break at or near that
    mileage?

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't Cinelli
    be fending off lawsuits left and right, presumably with your testimony as Exhibit A on why these
    things are unreasonably hazardous?

    Now, of course, just because something exists in the marketplace is no real evidence at all of its
    safety, design wisdom, etc. That is obvious. But the Cinelli crown has been around a long time, a
    lot of frames have been built using it, and if these facts resulted in a disproportionately large
    number of breakages (and, presumably in many -- though not all -- cases, resulting injuries), then
    wouldn't the tort system/products liability law force Cinelli to acknowledge a design defect?

    I know that you don't like the crown, and I have no reason to debate the engineering basis for
    your dislike. In terms of the design's drawbacks, I have to assume you are correct.

    I'm just asking, is it as failure prone as you say (i.e., reasonable expectation that a reasonable
    number of these things won't last over 5000 miles)?

    Ken Harper

  12. Ken Harper said:
    Quoted message said:
    Quoted message said:

    > The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end
    > abruptly (because no one can see this) and out of sight out of mind. However, fork blades fail
    > in fatigue at this transition, breaking off after an insignificant life duration. As I said, I
    > had tow of these failures and insisted on an external crown that was filed to have a zero
    > thickness transition. This has worked for many more miles than any of my Cinelli forks
    > survived.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    Quoted message said:
    Quoted message said:

    About 5000 miles.

    Quoted message said:

    I'm interested in your observations on this, and I want to make sure that I've got your statement
    clear: is it your experience that a Cinelli fully sloping crown can, and often does, fail by
    breaking fork blades at or around 5000 miles? Did the ones you write of break at or near that
    mileage?

    I did not say that. I responded to the question above. I don't know how long such forks last on the
    average and under whose use.

    Quoted message said:

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't Cinelli
    be fending off lawsuits left and right, presumably with your testimony as Exhibit A on why these
    things are unreasonably hazardous?

    It's much like the disc brake issue being debated in this news group. There is a distinct
    probability of failure but not a predictable one. The point is that this fork crown weighs about
    twice what far more durable ones do and it has a basic flaw. Steel frames have had shaped lugs to
    prevent stress concentrations from their earliest days. The sloping fork crown is a great leap
    backwards in that respect.

    Jobst Brandt [email hidden] Palo Alto CA

  13. Quoted message said:
    Quoted message said:

    "Thomas Hood" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Just curiousity but could you explain what you mean by "abrupt


    transition"

    Quoted message said:
    Quoted message said:

    and "feathered"?

    "Cinelli sloping crowns....are failure prone at the abrupt transition from fork blade to the
    internal lug of the crown that cannot be feathered to a gradual transition as an external lug
    can."

    By abrupt transition I assume you meant that internal lug looked


    like the

    Quoted message said:
    Quoted message said:

    LCO4 shown here: ceeway.comFork Crowns 2.htm
    I.e. the end of the lug is perpendicular to the blades and straight.

    However it would appear the Cinelli crown's end is not like this:
    ceeway.comFork Crowns.htm The Cinelli SCA, Everest C60, C61A, C63, Columbus MAX
    all seem to


    share

    Quoted message said:
    Quoted message said:

    this. Do these not have 'internally feathered' ends or have I


    misunderstood

    Quoted message said:

    you?

    The reason I ask is that I have just aquired an almost new Mercian fillet-brazed reynolds 653
    frame with said crown. Stunning


    craftmanship;

    Quoted message said:

    the

    Quoted message said:

    guy I bought it off had too much money to spend and had just


    'upgraded' to

    Quoted message said:

    a

    Quoted message said:

    giant carbon fibre compact!?! I'm not complaining he sold it to me


    for £75

    Quoted message said:
    Quoted message said:

    including a record f/mech and titanium seatpost. However after


    reading

    Quoted message said:

    your

    Quoted message said:

    'colostomy' incident story I'm a bit wary of that bit....

    Quoted message said:

    "A Muzi" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:

    Most Mercians I've seen, as most British bikes with that style crown,


    used a

    Quoted message said:

    Canetti rather than the Cinelli crown. ( You may know them best from


    Raleigh

    Quoted message said:

    Professionals, Raleigh Competitions and Holdsworth Pros) Canetti


    crowns are

    Quoted message said:

    thinner across the top between the blade and column. Cinellis are


    more

    Quoted message said:

    arched viewed from the front. Cinellis are "waisted" when viewed from above, Canettis are not,
    there being a flat face across the front and


    back.

    Quoted message said:

    Canettis end more abruptly inside than the later Cinelli which is


    shaped

    Quoted message said:

    such that there is more penetration in front and back than in the


    center of

    Quoted message said:

    the blade.

    "Jay Beattie" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:

    Andrew, I was wondering if Jobst's problems weren't caused in part by over-cooking -- heating up a
    big internal lug and forcing brass through a small seam. I understand the whole stress-riser thing
    (and it certainly makes sense), but I used Cinelli full sloping crowns for years (and high
    mileage) and never had a problem -- even a fork that was involved in a wall impact that resulted
    in the usual kink in the down-tube but no damage to the fork. I recently broke a 25 year old set
    of forks with a Cinelli semi-sloping crown, but then I had to drive my roof-rack mounted bike into
    a too low garage to do it. -- Jay Beattie.

    Are you speculating about brazing errors in a frame we've never seen, built by someone we do not
    know and cannot even name? That is silly.

    However, how many riders log as many miles as Jobst? In severe conditions like long descents
    regularly at speed? There may not have been anything "wrong" with his forks under a different rider
    who rides 500 miles per year and hangs it on the wall a lot.

    --
    Andrew Muzi yellowjersey.orgyellowjersey.org Open every day since 1 April 1971

  14. Tim Cain said:

    Part of this could be that very many bikes never see 500 miles usage, let alone 5000.

    Well, a lot of Cinellis saw more miles than that. But most of those miles were a long time ago,
    possibly predating the rush to litigation.

    --

    David L. Johnson

    __o | A mathematician is a machine for turning coffee into theorems. _`\(,_ | -- Paul Erdos
    (_)/ (_) |

  15. Quoted message said:

    It's much like the disc brake issue being debated in this news group. There is a distinct
    probability of failure but not a predictable one. The point is that this fork crown weighs about
    twice what far more durable ones do and it has a basic flaw. Steel frames have had shaped lugs to
    prevent stress concentrations from their earliest days. The sloping fork crown is a great leap
    backwards in that respect.

    Rather than calling something out of the past a "great leap backwards" I'd call it an old design
    that has flaws and has been greatly improved upon.

    As far as I know, that design is no longer in use today, and your "great leap backwards" might be
    misread by some.

    In the meantime, guess I'd better go check out my own Iron Pig (1973 Cinelli) that has well in
    excess of 50k miles on it... including some challenging rides in the Santa Cruz Mountains with some
    guy who knew all the secret roads & trails and streams to drink out of.

    --Mike-- Chain Reaction Bicycles chainreactionbicycles.comchainreactionbicycles.com

  16. [email hidden] (Scoochiro) wrote in message
    news:<[email hidden]>...

    Quoted message said:

    [email hidden] wrote in message
    news:<[email hidden]>...

    Quoted message said:
    K? Harper said:

    > The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end
    > abruptly (because no one can see this) and out of sight out of mind. However, fork blades
    > fail in fatigue at this transition, breaking off after an insignificant life duration. As I
    > said, I had tow of these failures and insisted on an external crown that was filed to have a
    > zero thickness transition. This has worked for many more miles than any of my Cinelli forks
    > survived.

    Quoted message said:
    Quoted message said:

    How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    I'm interested in your observations on this, and I want to make sure that I've got your statement
    clear: is it your experience that a Cinelli fully sloping crown can, and often does, fail by
    breaking fork blades at or around 5000 miles? Did the ones you write of break at or near that
    mileage?

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't Cinelli
    be fending off lawsuits left and right, presumably with your testimony as Exhibit A on why these
    things are unreasonably hazardous?

    Now, of course, just because something exists in the marketplace is no real evidence at all of its
    safety, design wisdom, etc. That is obvious. But the Cinelli crown has been around a long time, a
    lot of frames have been built using it, and if these facts resulted in a disproportionately large
    number of breakages (and, presumably in many -- though not all -- cases, resulting injuries), then
    wouldn't the tort system/products liability law force Cinelli to acknowledge a design defect?

    I know that you don't like the crown, and I have no reason to debate the engineering basis for
    your dislike. In terms of the design's drawbacks, I have to assume you are correct.

    I'm just asking, is it as failure prone as you say (i.e., reasonable expectation that a reasonable
    number of these things won't last over 5000 miles)?


    I don't think personal injury lawyers pay much attention to bicycles. Sure, there are some lawyers
    who advertise in the back of Velonews, etc., but they're probably suing drivers in most instances.
    If lawyers were constantly breathing down the necks of the bicycle industry, do you think we would
    be seeing ever lighter components, including things like titanium pedal spindles that we know break
    in fair numbers? How many decades did Campagnolo produce cranks that were prone to breaking? How
    many boutique companies come and go, putting ill-thought-out products on the market and then
    disappearing from view in a few summers?

    Personal injury lawyers are looking for deep pockets, quick turnaround, and the most bang for the
    buck (in other words, the biggest recovery given their investment in time and resources). Most
    bicycle accidents not involving cars are fairly minor compared to automobile accidents (and that
    automatically puts a limit on how much you can collect). If it involves a car, it's easier to go
    after the driver's insurer. Think about the effort involved in proving that Cinelli-style fork
    crowns are more dangerous than other designs. First, you'd have to get Cinelli and other fork makers
    to cough up a lot of proprietary data -- no mean effort. I believe it took months or years before
    lawyers suing Ford/Firestone realized that there was a pattern to SUV accidents. Ford and Firestone
    certainly weren't spreading the word.

    On the whole, even the biggest pockets in the bicycle world are small potatoes compared to the
    companies personal injury lawyers usually target.

    Yes, I'm aware that there are lawsuits against bike manufacturers and that some people have
    collected on frivolous claims. But I haven't seen that translate into any impact on bicycle design
    (with the possible exception of lawyer lips, and that was probably adopted as much because it was
    virtually costless as for any other reason -- just like you see warning stickers on some products
    instead of a redesign). I suspect lawsuits have their biggest impact on the bicycle industry in the
    form of higher insurance premiums, and little else.

    Have you been following the thread on James Annan's discovery regarding disk brakes? Perhaps
    there's something going on behind the scenes, but it looks like the industry wants to bury its head
    in the sand.

    I'm probably in the minority here, but I think the bicycle consumer might actually benefit from some
    well-targeted lawsuits against bicycle manufacturers. I don't expect to see it anytime soon, because
    the smart lawyers have bigger fish to fry.

    I'm not entirely hopeless about the situation though. I do think it's heartening that people like
    James Annan and the contributors to this newsgroup are trying to uncover patterns that the bicycle
    manufacturers are indifferent to or too lacking in resources to uncover. If we publicize these
    things, the manufacturers (or, perhaps more importantly, their insurers) will probably begin to
    take notice.

  17. [email hidden] wrote in message news:<[email hidden]>...

    Quoted message said:
    Ken Harper said:
    Quoted message said:

    >> The Cinelli crown has fairly thick lug extensions that go inside the fork blades and end
    >> abruptly (because no one can see this) and out of sight out of mind. However, fork blades
    >> fail in fatigue at this transition, breaking off after an insignificant life duration. As I
    >> said, I had tow of these failures and insisted on an external crown that was filed to have a
    >> zero thickness transition. This has worked for many more miles than any of my Cinelli forks
    >> survived.

    Quoted message said:
    Quoted message said:

    > How many miles constitute an "insignificant life duration"?

    Quoted message said:
    Quoted message said:

    About 5000 miles.

    Quoted message said:

    I'm interested in your observations on this, and I want to make sure that I've got your
    statement clear: is it your experience that a Cinelli fully sloping crown can, and often does,
    fail by breaking fork blades at or around 5000 miles? Did the ones you write of break at or near
    that mileage?

    I did not say that. I responded to the question above. I don't know how long such forks last on
    the average and under whose use.

    In deference to Richard, I will duly note that these are Cinelli-style crowns.

    (And I know that Richard has expressed some fondness for these types of crowns in the past. Richard:
    did you find there to be an unacceptable failure rate, or did your view of aesthetic issues change,
    or did something else cause you to adopt your now well-recognized own design?)

    Re Jobst's observations, I was just wondering if you had any basis to claim a "5000 mile life
    duration"? It would seem that you don't. Or it would seem that a "life duration" is something other
    than the point at which a fork crown fails (which is rather surprising, since these concepts seem
    quite synonymous).

    So, again granting that this is not the best designed fork crown, why wouldn't it have been just as
    accurate to claim a 10,000 mile "life duration"? If you don't know how long such forks last on the
    average and under whose use, then what would make the 5,000 mile number any more or less valid than
    a 25,000 mile number?

    I mean, I guess the whole point of my discussion is that you are well respected for your engineering
    knowledge of bicycles. Thus, I take your observations seriously, and even more so when there is a
    failure issue regarding something like a fork cown.

    So, the real question is, from my point of view, has your engineering knowledge been applied in a
    methodical way to reach the 5,000 mile number, or was that a dislike of the design coupled with a
    guess? Which is fine, too; I've certainly got my guesses on things as well.

    But a statement like "5000 mile life duration" is going to suggest to me, and the OP, at least, that
    this is not a particularly good bike to ride, at least not often.

    Is the following a valid conclusion from your statement: if I have a frame with at least 5,000 miles
    on it, and if it has such a crown, then I've already exceeded the crown's life duration, and I just
    might reasonably expect a failure at any point now?

    Ken Harper

  18. "A Muzi" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:
    Quoted message said:
    Quoted message said:

    "Thomas Hood" <[email hidden]> wrote in


    message

    Quoted message said:
    Quoted message said:
    Quoted message said:

    "]news:[email hidden]...
    > Just curiousity but could you explain what you mean by "abrupt


    transition"

    Quoted message said:

    > and "feathered"?
    >
    > "Cinelli sloping crowns....are failure prone at the abrupt transition from fork blade to the
    > internal lug of the crown that cannot be feathered to a gradual transition as an external
    > lug


    can."

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >
    > By abrupt transition I assume you meant that internal lug looked


    like the

    Quoted message said:

    > LCO4 shown here: ceeway.comFork Crowns 2.htm
    > I.e. the end of the lug is perpendicular to the blades and


    straight.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >
    > However it would appear the Cinelli crown's end is not like


    this:

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > ceeway.comFork Crowns.htm The Cinelli SCA, Everest C60, C61A, C63, Columbus MAX
    > all seem


    to

    Quoted message said:
    Quoted message said:

    share

    Quoted message said:

    > this. Do these not have 'internally feathered' ends or have I
    misunderstood
    > you?
    >
    > The reason I ask is that I have just aquired an almost new


    Mercian

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > fillet-brazed reynolds 653 frame with said crown. Stunning


    craftmanship;

    Quoted message said:

    the
    > guy I bought it off had too much money to spend and had just


    'upgraded' to

    Quoted message said:

    a
    > giant carbon fibre compact!?! I'm not complaining he sold it to


    me

    Quoted message said:
    Quoted message said:

    for £75

    Quoted message said:

    > including a record f/mech and titanium seatpost. However after


    reading

    Quoted message said:

    your
    > 'colostomy' incident story I'm a bit wary of that bit....

    Quoted message said:

    "A Muzi" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:

    Most Mercians I've seen, as most British bikes with that style


    crown,

    Quoted message said:
    Quoted message said:

    used a

    Quoted message said:

    Canetti rather than the Cinelli crown. ( You may know them best


    from

    Quoted message said:
    Quoted message said:

    Raleigh

    Quoted message said:

    Professionals, Raleigh Competitions and Holdsworth Pros) Canetti


    crowns are

    Quoted message said:

    thinner across the top between the blade and column. Cinellis


    are

    Quoted message said:
    Quoted message said:

    more

    Quoted message said:

    arched viewed from the front. Cinellis are "waisted" when viewed


    from

    Quoted message said:
    Quoted message said:
    Quoted message said:

    above, Canettis are not, there being a flat face across the front


    and

    Quoted message said:
    Quoted message said:

    back.

    Quoted message said:

    Canettis end more abruptly inside than the later Cinelli which is


    shaped

    Quoted message said:

    such that there is more penetration in front and back than in the


    center of

    Quoted message said:

    the blade.

    "Jay Beattie" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Andrew, I was wondering if Jobst's problems weren't caused in part


    by

    Quoted message said:
    Quoted message said:

    over-cooking -- heating up a big internal lug and forcing brass


    through

    Quoted message said:
    Quoted message said:

    a small seam. I understand the whole stress-riser thing (and it certainly makes sense), but I
    used Cinelli full sloping crowns for


    years

    Quoted message said:
    Quoted message said:

    (and high mileage) and never had a problem -- even a fork that was involved in a wall impact
    that resulted in the usual kink in the down-tube but no damage to the fork. I recently broke a
    25 year old


    set

    Quoted message said:
    Quoted message said:

    of forks with a Cinelli semi-sloping crown, but then I had to drive


    my

    Quoted message said:
    Quoted message said:

    roof-rack mounted bike into a too low garage to do it. -- Jay


    Beattie.

    Quoted message said:

    Are you speculating about brazing errors in a frame we've never seen,


    built

    Quoted message said:

    by someone we do not know and cannot even name? That is silly.

    Actually, I was wondering whether this was a problematic joint -- one prone to overheating. Silly or
    not, some lugs are harder to braze than others, and it seems to me that the internal plugs would be
    a big heat sink.

    Quoted message said:

    However, how many riders log as many miles as Jobst? In severe


    conditions

    Quoted message said:

    like long descents regularly at speed? There may not have been


    anything

    Quoted message said:

    "wrong" with his forks under a different rider who rides 500 miles


    per year

    Quoted message said:

    and hangs it on the wall a lot.

    Hell, in the '70s and 80s, I logged similar mileages living in the same neighborhood riding a bike
    with a full-sloping Cinelli crown -- and about 25lbs heavier than Jobst. 5,000 miles is not that
    far, regardless of the descents or the breaking forces (which, as I understand it, Jobst used
    sparingly). For a fairly devoted Master or Cat 3 in the Santa Clara Valley in the '70s and 80s, that
    would be about one racing season. This is why I thought there might have been some contribution to
    the failure from another source besides the design. -- Jay Beattie.

  19. "Gary Young" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    [email hidden] (Scoochiro) wrote in message


    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:

    [email hidden] wrote in message


    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:
    Quoted message said:

    K? Harper writes:

    >> The Cinelli crown has fairly thick lug extensions that go


    inside the

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> fork blades and end abruptly (because no one can see this) and


    out of

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> sight out of mind. However, fork blades fail in fatigue at


    this

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> transition, breaking off after an insignificant life duration.


    As I

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> said, I had tow of these failures and insisted on an external


    crown

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> that was filed to have a zero thickness transition. This has


    worked

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> for many more miles than any of my Cinelli forks survived.

    Quoted message said:

    > How many miles constitute an "insignificant life duration"?

    About 5000 miles.

    I'm interested in your observations on this, and I want to make sure that I've got your
    statement clear: is it your experience that a Cinelli fully sloping crown can, and often does,
    fail by breaking


    fork

    Quoted message said:
    Quoted message said:

    blades at or around 5000 miles? Did the ones you write of break at


    or

    Quoted message said:
    Quoted message said:

    near that mileage?

    Maybe I have misconstrued your statement but, if not, then I find it hard to believe. Since fork
    crowns are made to be ridden, and since they are an integral part of the steering/safety of a
    bicycle, and since we have no shortage of plaintiffs lawyers in this country, why wouldn't
    Cinelli be fending off lawsuits left and right, presumably with your testimony as Exhibit A on
    why these things are


    unreasonably

    Quoted message said:
    Quoted message said:

    hazardous?

    Now, of course, just because something exists in the marketplace is


    no

    Quoted message said:
    Quoted message said:

    real evidence at all of its safety, design wisdom, etc. That is obvious. But the Cinelli crown
    has been around a long time, a lot


    of

    Quoted message said:
    Quoted message said:

    frames have been built using it, and if these facts resulted in a disproportionately large
    number of breakages (and, presumably in


    many

    Quoted message said:
    Quoted message said:

    -- though not all -- cases, resulting injuries), then wouldn't the tort system/products
    liability law force Cinelli to acknowledge a design defect?

    I know that you don't like the crown, and I have no reason to debate the engineering basis for
    your dislike. In terms of the design's drawbacks, I have to assume you are correct.

    I'm just asking, is it as failure prone as you say (i.e., reasonable expectation that a
    reasonable number of these things won't last over 5000 miles)?


    I don't think personal injury lawyers pay much attention to bicycles. Sure, there are some lawyers
    who advertise in the back of Velonews, etc., but they're probably suing drivers in most instances.
    If lawyers were constantly breathing down the necks of the bicycle industry, do you think we would
    be seeing ever lighter components, including things like titanium pedal spindles that we know
    break in fair numbers? How many decades did Campagnolo produce cranks that were prone to breaking?
    How many boutique companies come and go, putting ill-thought-out products on the market and then
    disappearing from view in a few summers?

    Actually, PI lawyers love a good bicycle-related products liability law suit. They do not present
    the same problems as an auto versus bicycle case (drivers are jurors) and are usually subject to
    much higher insurance limits. The "problem" is that bicycles and components do not often break in a
    way that causes serious injury. I have broken four or five cranks, and never so much as fell off my
    bike or smashed my privates.

    Quoted message said:

    Personal injury lawyers are looking for deep pockets, quick turnaround, and the most bang for the
    buck (in other words, the biggest recovery given their investment in time and resources). Most
    bicycle accidents not involving cars are fairly minor compared to automobile accidents (and that
    automatically puts a limit on how much you can collect). If it involves a car, it's easier to go
    after the driver's insurer. Think about the effort involved in proving that Cinelli-style fork
    crowns are more dangerous than other designs. First, you'd have to get Cinelli and other fork
    makers to cough up a lot of proprietary data -- no mean effort. I believe it took months or years
    before lawyers suing Ford/Firestone realized that there was a pattern to SUV accidents. Ford and
    Firestone certainly weren't spreading the word.

    This would be an easy strict liability case against Cinelli or the American distributor. One
    expert, maybe two, to testify that the internal lug creates a stress-riser which results in the
    early failure of the fork. Assuming that there is a pattern of failures, go for punitive damages.
    Put those Italians out of business ladies and gentlemen. Remember Mussolini? Remeber the Fiat? I
    am outraged!

    <snip>

    Quoted message said:

    Yes, I'm aware that there are lawsuits against bike manufacturers and that some people have
    collected on frivolous claims. But I haven't seen that translate into any impact on bicycle design
    (with the possible exception of lawyer lips, and that was probably adopted as much because it was
    virtually costless as for any other reason -- just like you see warning stickers on some products
    instead of a redesign). I suspect lawsuits have their biggest impact on the bicycle industry in
    the form of higher insurance premiums, and little else.

    Design changes are frequently made to address consumer complaints and in response to law suits.
    Changes that come to mind that were driven in part by law suits include the demise of the 5mm cap
    screw/fork crown on mountain bikes; gussets on Al frames, wheel retention devices, endless warning
    labels and disclaimers in manuals and handbooks, reflectors, lights (although this has not taken off
    after the Derby case). Think of all the recalled products. The CPSC and SNELL/ANSI have requirements
    which may result from incident reports or complaints that also turned into lawsuits.

    <snip>

    Quoted message said:

    I'm not entirely hopeless about the situation though. I do think it's heartening that people like
    James Annan and the contributors to this newsgroup are trying to uncover patterns that the bicycle
    manufacturers are indifferent to or too lacking in resources to uncover. If we publicize these
    things, the manufacturers (or, perhaps more importantly, their insurers) will probably begin to
    take notice.

    I doubt the domestic manufacturers are indifferent. I have spent a lot of time representing several
    domestic manufacturers and found that they did extensive and expensive testing on their products.
    There are some foreign OEM manufacturers who are less diligent, IMO, and absent close oversight from
    the American customer, may come up with a dangerous look-alike product. -- Jay Beattie.

  20. Gary Young said:

    I don't think personal injury lawyers pay much attention to bicycles. Sure, there are some lawyers
    who advertise in the back of Velo news, etc., but they're probably suing drivers in most
    instances. If lawyers were constantly breathing down the necks of the bicycle industry, do you
    think we would be seeing ever lighter components, including things like titanium pedal spindles
    that we know break in fair numbers? How many decades did Campagnolo produce cranks that were prone
    to breaking? How many boutique companies come and go, putting ill-thought-out products on the
    market and then disappearing from view in a few summers?

    I think you hypothesize about law suits of which you are apparently unaware. I have testified as an
    expert witness in defense of the bicycle industry against many weird claims. In most of these there
    have been other 'expert' witnesses who will testify to anything a plaintiff claims. I have testified
    against such experts in most cases of which none had any merit. These cases are generally taken
    under contingency and after I have shown that the claims are unsupportable, cases are generally
    settled, everyone getting a little payoff including the plaintiff (liar) and the game starts over.
    In contrast, most Japanese firms demand a judgment even if the legal fees are greater, in the
    interest of setting precedence. I favor that approach.

    Jobst Brandt [email hidden] Palo Alto CA

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