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Question About Cranks

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Cycling Equipment
Published
3 September 2007
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10 September 2007
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George
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  1. email hidden said:

    Not paying to use a patent and thus not making a product is a Shimano
    trait.

    Frank Berto talks about this in The Dancing Chain, how SIS's
    introduction coincided with and was dependent upon the expiration of
    Suntour's patent on Slant-Parallellogram RDs. Shimano combined SP
    geometry with dual pivot springs to maintain constant jockey pulley
    distance. That enabled shifting without overshifting, which is
    necessary for good indexing.

  2. Quoted message said:
    Quoted post said:

    Not paying to use a patent and thus not making a product is a Shimano
    trait.

    Hank Wirtz said:

    Frank Berto talks about this in The Dancing Chain, how SIS's
    introduction coincided with and was dependent upon the expiration of
    Suntour's patent on Slant-Parallellogram RDs. Shimano combined SP
    geometry with dual pivot springs to maintain constant jockey pulley
    distance. That enabled shifting without overshifting, which is
    necessary for good indexing.

    The first DA SIS, even later New 600EX SIS were not
    slant-parallelogram. But, yes it was a big improvement.
    I think chain snap links make another instance.
    --
    Andrew Muzi
    www.yellowjersey.org
    Open every day since 1 April, 1971

  3. Ryan Cousineau said:
    Quoted message said:
    Quoted message said:

    >>> Shimano pioneered this style, with their "Hollowtech II" system,
    >>> but now most of the major crank manufacturers have followed suit.

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

    >> "Pioneered"??? Well, maybe the external bearings, but Bullseye
    >> created two-piece cranks somewhere around the Cretaceous era:
    >> http://www.bikepro.com/products/cranks/bullseye.html

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

    > Yeah, my 1950s Magistroni steel crank has a similar pinch bolt on a
    > splined spindle. The Thun crank system has a spindle integral to
    > the right crank like DA, a splined spindle like DA, a left slit
    > crank with pinch bolt like DA, c. 1950s as well.

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

    When you think about it the spindle should be integrated with the
    non-drive sided (left) crank. It is the NDS to spindle attachment
    that must transmit substantial pedaling torque, while the DS crank
    attaches itself to the spider, and thence to the chain rings. Hey!
    Who's in charge here?

    Quoted message said:
    Quoted message said:

    If you consider how to attach a spindle to a crank and what torque the
    spindle transmits you probably would do as others have and put pinch
    bolts on the left crank and permanently anchor the spindle in the
    right crank. The Campagnolo method is more complex and expensive. I
    think they ran into patent problems and came up with theirs as a way
    out.

    Quoted message said:
    Quoted message said:

    You'll note that Shimano uses two pinch bolts, showing that they gave
    this some thought and experimentation. I don't see how you propose to
    locate such hardware on the right crank, and beyond that for what
    reason. All torque that goes through the spindle is transmitted at
    both ends equally. The V-shaped spline is used because it lends
    itself to no-backlash attachment (something Octalink did not do) if
    the mating part is clamped onto it.

    Quoted message said:

    As if to baffle us all, the latest XTR design uses a non pinch-bolt
    attachment, as most clearly shown in this exploded diagram PDF:

    Quoted message said:

    http://bike.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV-FC-M970-2592_v1_m56577569830608898.pdf

    This is an Octalink attachment that unscrews the retaining bolt and
    shears the end of the 8-spline in the aluminum crank (for right foot
    forward standees). That there are many such riders and that this
    causes reverse torque in the spindle seems to have escaped the
    originator of the Octalink.

    Not only that, but the same designers assumed sheared spines were
    caused by insufficient engagement length and made a second longer
    version that suffers these same failures. The pinch bolt design for
    attachment of the crank is superior because it has no elastic backlash
    (that unscrews Octalinks) and can withstand recerse torqu that occurs
    only when standing on both pedals with the right foot forward.

    Quoted message said:

    Basically, there's a "crank arm fixing bolt unit" that screws into the
    end of the spindle, along with an "adjust nut" that apparently goes
    between the crank arm and the BB shell, and which itself is held in
    place with a pinch bolt. But note that the adjust nut is threaded
    to...the inside of the left crank arm?!

    Quoted message said:

    Deeply worrying installation instructions here:

    http://bike.shimano.com/media/techdocs/content/cycle/SI/XTR/FC-M970/15H0A_EN_v1_m56577569830600538.PDF

    Quoted message said:

    For those of you who aren't MTBers, note that XT has historically
    suffered from some of the same sorts of unique-bits weirdness that
    Dura-Ace occasionally experiences.

    Sounds interesting. Please fill me in.

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

    > I think Sheldon's choice of 'pioneered' wasn't the best word but
    > his meaning was otherwise clear.

    Jobst Brandt

  4. On Wed, 05 Sep 2007 05:04:40 +0000, Ryan Cousineau wrote:

    <snip>

    Quoted message said:

    As if to baffle us all, the latest XTR design uses a non pinch-bolt
    attachment, as most clearly shown in this exploded diagram PDF:

    http://bike.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC
    /EV-FC-M970-2592_v1_m56577569830608898.pdf

    Basically, there's a "crank arm fixing bolt unit" that screws into the
    end of the spindle, along with an "adjust nut" that apparently goes
    between the crank arm and the BB shell, and which itself is held in
    place with a pinch bolt. But note that the adjust nut is threaded
    to...the inside of the left crank arm?!

    Deeply worrying installation instructions here:

    http://bike.shimano.com/media/techdocs/content/cycle/SI/XTR/FC-M970/15H0A
    _EN_v1_m56577569830600538.PDF

    For those of you who aren't MTBers, note that XT has historically
    suffered from some of the same sorts of unique-bits weirdness that
    Dura-Ace occasionally experiences.

    I'm not sure where I saw this, but one of the sites covering Eurobike said
    that Shimano's new carbon-fiber crank is going to use the same setup as
    the new XTR.

  5. A Muzi said:
    Quoted message said:
    Quoted post said:

    Not paying to use a patent and thus not making a product is a Shimano
    trait.


    Hank Wirtz said:

    Frank Berto talks about this in The Dancing Chain, how SIS's
    introduction coincided with and was dependent upon the expiration of
    Suntour's patent on Slant-Parallellogram RDs. Shimano combined SP
    geometry with dual pivot springs to maintain constant jockey pulley
    distance. That enabled shifting without overshifting, which is
    necessary for good indexing.

    The first DA SIS, even later New 600EX SIS were not
    slant-parallelogram.

    But they *were* slant parallelogram. I had a D-A RD-7400 from '85 to
    '90. It was basically identical to the D-A RD-7402 that is still on
    one of my bikes.

  6. Quoted message said:
    Quoted message said:
    Quoted message said:

    "[email hidden]" <[email hidden]> wrote:
    > Not paying to use a patent and thus not making a product is a Shimano
    > trait.

    Quoted message said:
    Quoted message said:
    Hank Wirtz said:

    Frank Berto talks about this in The Dancing Chain, how SIS's
    introduction coincided with and was dependent upon the expiration of
    Suntour's patent on Slant-Parallellogram RDs. Shimano combined SP
    geometry with dual pivot springs to maintain constant jockey pulley
    distance. That enabled shifting without overshifting, which is
    necessary for good indexing.

    Quoted message said:

    A Muzi <[email hidden]> screwed up:

    Quoted message said:

    The first DA SIS, even later New 600EX SIS were not
    slant-parallelogram.

    Ozark Bicycle said:

    But they *were* slant parallelogram. I had a D-A RD-7400 from '85 to
    '90. It was basically identical to the D-A RD-7402 that is still on
    one of my bikes.

    I was off a by a year. Earlier I looked at the 1983 New 600 6207 which
    like all Shimano rears though 1983 (Deore XT too) are "Servo Pantograph"
    not slanted.

    I just found the later book. The autumn 1983 for 1984 model year book
    shows the first SIS system 7400, as Hank noted, Slant bodied. The New
    600 moves to a slant 6208 design along with everything else after that.
    --
    Andrew Muzi
    www.yellowjersey.org
    Open every day since 1 April, 1971

  7. A Muzi said:
    Quoted message said:
    Quoted post said:

    Not paying to use a patent and thus not making a product is a Shimano
    trait.


    Hank Wirtz said:

    Frank Berto talks about this in The Dancing Chain, how SIS's
    introduction coincided with and was dependent upon the expiration of
    Suntour's patent on Slant-Parallellogram RDs. Shimano combined SP
    geometry with dual pivot springs to maintain constant jockey pulley
    distance. That enabled shifting without overshifting, which is
    necessary for good indexing.

    The first DA SIS, even later New 600EX SIS were not
    slant-parallelogram. But, yes it was a big improvement.
    I think chain snap links make another instance.
    --
    Andrew Muziwww.yellowjersey.org
    Open every day since 1 April, 1971

    I have the book open, and the exploded diagram sure looks like a slant
    parallelogram; Berto also makes a big deal about what a breakthrough
    the RD-7400 was, and how every RD made today is rooted in its design.

    I'm gonna side with Berto, here.

  8. Quoted message said:
    Quoted message said:
    Quoted message said:

    "[email hidden]" <[email hidden]> wrote:
    > Not paying to use a patent and thus not making a product is a Shimano
    > trait.

    Quoted message said:
    Quoted message said:
    Hank Wirtz said:

    Frank Berto talks about this in The Dancing Chain, how SIS's
    introduction coincided with and was dependent upon the expiration of
    Suntour's patent on Slant-Parallellogram RDs. Shimano combined SP
    geometry with dual pivot springs to maintain constant jockey pulley
    distance. That enabled shifting without overshifting, which is
    necessary for good indexing.

    Quoted message said:

    A Muzi <[email hidden]> erred:

    Quoted message said:

    The first DA SIS, even later New 600EX SIS were not
    slant-parallelogram. But, yes it was a big improvement.
    I think chain snap links make another instance.

    Hank Wirtz said:

    I have the book open, and the exploded diagram sure looks like a slant
    parallelogram; Berto also makes a big deal about what a breakthrough
    the RD-7400 was, and how every RD made today is rooted in its design.
    I'm gonna side with Berto, here.

    mea culpa, I was in the 1983 book and you're right.
    --
    Andrew Muzi
    www.yellowjersey.org
    Open every day since 1 April, 1971

  9. In article <[email hidden]>,

    Quoted message said:
    Ryan Cousineau said:
    Quoted message said:

    >>>> Shimano pioneered this style, with their "Hollowtech II" system,
    >>>> but now most of the major crank manufacturers have followed suit.

    Quoted message said:
    Quoted message said:

    >>> "Pioneered"??? Well, maybe the external bearings, but Bullseye
    >>> created two-piece cranks somewhere around the Cretaceous era:
    >>> http://www.bikepro.com/products/cranks/bullseye.html

    Quoted message said:
    Quoted message said:

    >> Yeah, my 1950s Magistroni steel crank has a similar pinch bolt on a
    >> splined spindle. The Thun crank system has a spindle integral to
    >> the right crank like DA, a splined spindle like DA, a left slit
    >> crank with pinch bolt like DA, c. 1950s as well.

    Quoted message said:
    Quoted message said:

    > When you think about it the spindle should be integrated with the
    > non-drive sided (left) crank. It is the NDS to spindle attachment
    > that must transmit substantial pedaling torque, while the DS crank
    > attaches itself to the spider, and thence to the chain rings. Hey!
    > Who's in charge here?

    Quoted message said:
    Quoted message said:

    If you consider how to attach a spindle to a crank and what torque the
    spindle transmits you probably would do as others have and put pinch
    bolts on the left crank and permanently anchor the spindle in the
    right crank. The Campagnolo method is more complex and expensive. I
    think they ran into patent problems and came up with theirs as a way
    out.

    Quoted message said:
    Quoted message said:

    You'll note that Shimano uses two pinch bolts, showing that they gave
    this some thought and experimentation. I don't see how you propose to
    locate such hardware on the right crank, and beyond that for what
    reason. All torque that goes through the spindle is transmitted at
    both ends equally. The V-shaped spline is used because it lends
    itself to no-backlash attachment (something Octalink did not do) if
    the mating part is clamped onto it.

    Quoted message said:

    As if to baffle us all, the latest XTR design uses a non pinch-bolt
    attachment, as most clearly shown in this exploded diagram PDF:

    Quoted message said:

    http://bike.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV
    -FC-M970-2592_v1_m56577569830608898.pdf

    This is an Octalink attachment that unscrews the retaining bolt and
    shears the end of the 8-spline in the aluminum crank (for right foot
    forward standees). That there are many such riders and that this
    causes reverse torque in the spindle seems to have escaped the
    originator of the Octalink.

    Well, it may be Octalink-style, but Shimano will assure you that it is
    "XTR Hollowtech II" or some such.

    Quoted message said:

    Not only that, but the same designers assumed sheared spines were
    caused by insufficient engagement length and made a second longer
    version that suffers these same failures. The pinch bolt design for
    attachment of the crank is superior because it has no elastic backlash
    (that unscrews Octalinks) and can withstand recerse torqu that occurs
    only when standing on both pedals with the right foot forward.

    Quoted message said:

    Basically, there's a "crank arm fixing bolt unit" that screws into the
    end of the spindle, along with an "adjust nut" that apparently goes
    between the crank arm and the BB shell, and which itself is held in
    place with a pinch bolt. But note that the adjust nut is threaded
    to...the inside of the left crank arm?!

    Quoted message said:

    Deeply worrying installation instructions here:

    http://bike.shimano.com/media/techdocs/content/cycle/SI/XTR/FC-M970/15H0A_EN_
    v1_m56577569830600538.PDF

    Quoted message said:

    For those of you who aren't MTBers, note that XT has historically
    suffered from some of the same sorts of unique-bits weirdness that
    Dura-Ace occasionally experiences.

    Sounds interesting. Please fill me in.

    First off, I must correct myself: "XTR", not XT. When Deore XT was
    introduced, it was the top MTB group. It was superseded by XTR (never
    "Deore XTR" though "XT" is still nominally "Deore XT", not to be
    confused with the lesser "Deore" and "Deore LX" groups. Even I would
    have to look it up to tell you the order of precedence of the lesser
    Altus, Acera, and Alivio groups...), which persists as the
    light-and-pricey group.

    Notable oddities:

    http://www.retroraleighs.com/cribsheet-bcd.html

    Note the XTR-only 112/68 4-bolt BCD, now superseded by a single BCD
    standard for all Shimano 4-bolt (basically, all MTB) cranks, including
    the latest XTR (think of the unique Dura-Ace triple BCD).

    Those rings are the only purely orphan part I can think of. I had
    falsely assumed that XTR was the only group that used the Dual-Control
    system (basically, shifting is incorporated into the brake lever; this
    is more weird on an MTB than on a road bike), but that has trickled down
    two groups to Deore LX and XT.

    XTR was also the

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

    >> I think Sheldon's choice of 'pioneered' wasn't the best word but
    >> his meaning was otherwise clear.

    Jobst Brandt

    --
    Ryan Cousineau [email hidden] http://www.wiredcola.com/
    "I don't want kids who are thinking about going into mathematics
    to think that they have to take drugs to succeed." -Paul Erdos

  10. Ryan Cousineau said:

    In article <[email hidden]>,

    Quoted message said:

    Those rings are the only purely orphan part I can think of. I had
    falsely assumed that XTR was the only group that used the Dual-Control
    system (basically, shifting is incorporated into the brake lever; this
    is more weird on an MTB than on a road bike), but that has trickled down
    two groups to Deore LX and XT.

    Three. Deore got them this year. I think these are gonna go the way of
    Biopace rings: some people love them, most don't, so they're gonna go
    away after this last push.

  11. Quoted message said:
    Ryan Cousineau said:
    Quoted message said:

    >>>> Shimano pioneered this style, with their "Hollowtech II" system,
    >>>> but now most of the major crank manufacturers have followed suit.

    Quoted message said:
    Quoted message said:

    >>> "Pioneered"??? Well, maybe the external bearings, but Bullseye
    >>> created two-piece cranks somewhere around the Cretaceous era:
    >>> http://www.bikepro.com/products/cranks/bullseye.html

    Quoted message said:
    Quoted message said:

    >> Yeah, my 1950s Magistroni steel crank has a similar pinch bolt on a
    >> splined spindle. The Thun crank system has a spindle integral to
    >> the right crank like DA, a splined spindle like DA, a left slit
    >> crank with pinch bolt like DA, c. 1950s as well.

    Quoted message said:
    Quoted message said:

    > When you think about it the spindle should be integrated with the
    > non-drive sided (left) crank. It is the NDS to spindle attachment
    > that must transmit substantial pedaling torque, while the DS crank
    > attaches itself to the spider, and thence to the chain rings. Hey!
    > Who's in charge here?

    Quoted message said:
    Quoted message said:

    If you consider how to attach a spindle to a crank and what torque the
    spindle transmits you probably would do as others have and put pinch
    bolts on the left crank and permanently anchor the spindle in the
    right crank. The Campagnolo method is more complex and expensive. I
    think they ran into patent problems and came up with theirs as a way
    out.

    Quoted message said:
    Quoted message said:

    You'll note that Shimano uses two pinch bolts, showing that they gave
    this some thought and experimentation. I don't see how you propose to
    locate such hardware on the right crank, and beyond that for what
    reason. All torque that goes through the spindle is transmitted at
    both ends equally. The V-shaped spline is used because it lends
    itself to no-backlash attachment (something Octalink did not do) if
    the mating part is clamped onto it.

    Quoted message said:

    As if to baffle us all, the latest XTR design uses a non pinch-bolt
    attachment, as most clearly shown in this exploded diagram PDF:

    Quoted message said:

    http://bike.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV-FC-M970-2592_v1_m56577569830608898.pdf

    This is an Octalink attachment that unscrews the retaining bolt and
    shears the end of the 8-spline in the aluminum crank (for right foot
    forward standees).

    no it doesn't. not only does over a decade of usage prove you wrong in
    practice, you failed to observe the radiused tooth roots on these
    interfaces which prevent this in theory too.

    Quoted message said:

    That there are many such riders and that this
    causes reverse torque in the spindle seems to have escaped the
    originator of the Octalink.

    what? like fatigue not being eliminated in non strain-aging materials
    you mean?

    Quoted message said:


    Not only that, but the same designers assumed sheared spines were
    caused by insufficient engagement length and made a second longer
    version that suffers these same failures. The pinch bolt design for
    attachment of the crank is superior because it has no elastic backlash
    (that unscrews Octalinks) and can withstand recerse torqu that occurs
    only when standing on both pedals with the right foot forward.

    but it doesn't.

    Quoted message said:


    Quoted message said:

    Basically, there's a "crank arm fixing bolt unit" that screws into the
    end of the spindle, along with an "adjust nut" that apparently goes
    between the crank arm and the BB shell, and which itself is held in
    place with a pinch bolt. But note that the adjust nut is threaded
    to...the inside of the left crank arm?!

    Quoted message said:

    Deeply worrying installation instructions here:

    http://bike.shimano.com/media/techdocs/content/cycle/SI/XTR/FC-M970/15H0A_EN_v1_m56577569830600538.PDF

    Quoted message said:

    For those of you who aren't MTBers, note that XT has historically
    suffered from some of the same sorts of unique-bits weirdness that
    Dura-Ace occasionally experiences.

    Sounds interesting. Please fill me in.

    Quoted message said:
    Quoted message said:

    >> I think Sheldon's choice of 'pioneered' wasn't the best word but
    >> his meaning was otherwise clear.


    same [censored], different day.

  12. Chalo said:
    Ryan Cousineau said:

    JeffWills wrote:

    Quoted message said:
    Quoted message said:

    Sheldon Brown wrote:

    Quoted message said:
    Quoted message said:

    > Shimano pioneered this style, with their "Hollowtech II" system, but
    > now most of the major crank manufacturers have followed suit.

    Quoted message said:
    Quoted message said:

    "Pioneered"??? Well, maybe the external bearings, but Bullseye created
    two-piece cranks somewhere around the Cretaceous era:
    http://www.bikepro.com/products/cranks/bullseye.html

    Quoted message said:

    I think external bearings may have been what Sheldon was referring to,
    along with the application to road bikes and MTBs.

    Magic Motorcycle made their cranks with big-tube spindles and external
    bearings a long time ago (early '90s?). http://patineto.smugmug.com/photos/53289989-O.jpg

    I made an external bearing BB for my own bike in 1999:http://picasaweb.google.com/chalo.colina/RedBike/photo#51067828464183...

    Shimano not only used the patented Bullseye design for their cranks,
    but they waited a long time to let Roger Durham's patent expire while
    producing a variety of inferior, sometimes defective alternatives.
    Saying Shimano pioneered any part of the Hollowtech II system is
    giving them far too much credit, and is unfair to real innovators in
    the business.

    Chalo

    Bulleye pioneered tubular steel tig welded cranks. Magic Motorcycle
    pioneered glued aluminum CNC'd clamshells. Shimano's innovation was
    forged U shaped cranks (similar to many others) but with an aluminum
    plate welded on teh backside to close the U. Thus hollow forged welded
    cranks and I think that was a true first in production. The only
    innovation they all shared is the integrated spindle.

  13. Chalo said:
    Ryan Cousineau said:

    JeffWills wrote:

    Quoted message said:
    Quoted message said:

    Sheldon Brown wrote:

    Quoted message said:
    Quoted message said:

    > Shimano pioneered this style, with their "Hollowtech II" system, but
    > now most of the major crank manufacturers have followed suit.

    Quoted message said:
    Quoted message said:

    "Pioneered"??? Well, maybe the external bearings, but Bullseye created
    two-piece cranks somewhere around the Cretaceous era:
    http://www.bikepro.com/products/cranks/bullseye.html

    Quoted message said:

    I think external bearings may have been what Sheldon was referring to,
    along with the application to road bikes and MTBs.

    Magic Motorcycle made their cranks with big-tube spindles and external
    bearings a long time ago (early '90s?). http://patineto.smugmug.com/photos/53289989-O.jpg

    I made an external bearing BB for my own bike in 1999:http://picasaweb.google.com/chalo.colina/RedBike/photo#51067828464183...

    Shimano not only used the patented Bullseye design for their cranks,
    but they waited a long time to let Roger Durham's patent expire while
    producing a variety of inferior, sometimes defective alternatives.
    Saying Shimano pioneered any part of the Hollowtech II system is
    giving them far too much credit, and is unfair to real innovators in
    the business.

    Chalo

    Bulleye pioneered tubular steel tig welded cranks. Magic Motorcycle
    pioneered glued aluminum CNC'd clamshells. Shimano's innovation was
    forged U shaped cranks (similar to many others) but with an aluminum
    plate welded on teh backside to close the U. Thus hollow forged welded
    cranks and I think that was a true first in production. The only
    innovation they all shared/copied is the integrated spindle.

  14. velodancer said:
    Chalo said:
    Ryan Cousineau said:

    JeffWills wrote:
    > Sheldon Brown wrote:
    >> Shimano pioneered this style, with their "Hollowtech II" system, but
    >> now most of the major crank manufacturers have followed suit.
    > "Pioneered"??? Well, maybe the external bearings, but Bullseye created
    > two-piece cranks somewhere around the Cretaceous era:
    > http://www.bikepro.com/products/cranks/bullseye.html
    I think external bearings may have been what Sheldon was referring to,
    along with the application to road bikes and MTBs.


    Magic Motorcycle made their cranks with big-tube spindles and external
    bearings a long time ago (early '90s?). http://patineto.smugmug.com/photos/53289989-O.jpg

    I made an external bearing BB for my own bike in 1999:http://picasaweb.google.com/chalo.colina/RedBike/photo#51067828464183...

    Shimano not only used the patented Bullseye design for their cranks,
    but they waited a long time to let Roger Durham's patent expire while
    producing a variety of inferior, sometimes defective alternatives.
    Saying Shimano pioneered any part of the Hollowtech II system is
    giving them far too much credit, and is unfair to real innovators in
    the business.

    Chalo

    Bulleye pioneered tubular steel tig welded cranks. Magic Motorcycle
    pioneered glued aluminum CNC'd clamshells. Shimano's innovation was
    forged U shaped cranks (similar to many others) but with an aluminum
    plate welded on teh backside to close the U.

    i don't agree that that is the fabrication route. shimano may have a
    protective patent on that fab route for legal purposes, but that doesn't
    mean they actually use it. and the ones i saw at a shop in berkeley, ca
    contradict that fab route too. they had 3 different crank blanks
    showing stages of fabrication:

    1. solid flat - wide in the middle.
    2. bent around
    3. cold pressure "welded" closed.

    but the most compelling argument against is that the most fatigue
    resistant aluminum fabrication route is cold forging - fusion welding
    destroys the microstructure that the cold forging creates. and 2000
    series alloys, which shimano say they use on dura-ace for instance, is
    /not/ typically weldable.

    Quoted message said:

    Thus hollow forged welded
    cranks and I think that was a true first in production. The only
    innovation they all shared/copied is the integrated spindle.


  15. Quoted message said:
    Michael Press said:

    When you think about it the spindle should be integrated with the
    non-drive sided (left) crank. It is the NDS to spindle attachment
    that must transmit substantial pedaling torque, while the DS crank
    attaches itself to the spider, and thence to the chain rings. Hey!
    Who's in charge here?

    Jobst Brandt said:

    If you consider how to attach a spindle to a crank and what torque the
    spindle transmits you probably would do as others have and put pinch
    bolts on the left crank and permanently anchor the spindle in the
    right crank. The Campagnolo method is more complex and expensive. I
    think they ran into patent problems and came up with theirs as a way
    out.


    [snip]

    Both of y'all should take a look and the new Crank Bros cranks:
    Triple: http://tinyurl.com/39fdnf
    Single: http://tinyurl.com/34r7jz

    I can't quite tell how the non-drive side crank will secure itself on to
    the bottom bracket. Should be interesting to see how these perform.

    \\paul

  16. Quoted message said:
    Jay Beattie said:

    I didn't look at the advertising material, but I think that one
    problem Campagnolo was trying to solve has to do with the loose fit
    between the inner bearing races and the spindle on Shimano cranks
    which, according to some, causes wear on the spindle. Campagnolo has
    bearings that are press fit on to the spindle. I have an Ultegra
    that seems to be doing fine so far.

    As I have mentioned in earlier discussion about BB design, it's a huge
    can of worms and I don't see an easy solution to the bearing problem
    although I believe the crank attachment that Shimano has is a clean
    one that should work reliably. Their outboard bearing can't be good
    considering that inboard cups have failed on the right side from
    fretting, fretting that has a red flag on it because it requires a
    left hand thread, the best indicator of micro-motion.

    The point you mention is another headache for which I see no solution
    with the present design. This is such a high load interface that a
    slip fit bearing has got to fret and leave rouge traces from wear. I
    haven't worked with this BB but just looking at it at InterBike gave
    me reason to stay clear of it, considering how many cranks and
    spindles have withered under my feet.

    We'll have to wait and see.

    Jobst Brandt

    I'm surprised no-one has mentioned that 2008 will see the external
    bearing start to disappear.
    Shimano: http://preview.tinyurl.com/yth9j3
    Trek: http://www.trekbikes.com/madone/technology/efficiency/

    The differernce between the two systems is that the Trek 'drops' a
    bare bearing in, whereas the Shimano needs a 'press fit'. I'd be
    surprised if special tools were actually _needed_ to fit remove the
    Shimano effort though. I wonder what seals -- if any -- either system
    use.

    Thomas Hood

  17. Paul Myron Hobson said:

    I can't quite tell how the non-drive side crank will secure itself on to


    xxxxxxxxxxxxxx
    durrrrr. that should be *drive side*

  18. Paul Myron Hobson said:
    Quoted message said:
    Quoted message said:

    When you think about it the spindle should be integrated with the
    non-drive sided (left) crank. It is the NDS to spindle attachment
    that must transmit substantial pedaling torque, while the DS crank
    attaches itself to the spider, and thence to the chain rings. Hey!
    Who's in charge here?

    Quoted message said:
    Quoted message said:

    If you consider how to attach a spindle to a crank and what torque the
    spindle transmits you probably would do as others have and put pinch
    bolts on the left crank and permanently anchor the spindle in the
    right crank. The Campagnolo method is more complex and expensive. I
    think they ran into patent problems and came up with theirs as a way
    out.

    Quoted message said:

    Both of y'all should take a look and the new Crank Bros cranks:

    Triple: http://tinyurl.com/39fdnf
    Single: http://tinyurl.com/34r7jz

    Quoted message said:

    I can't quite tell how the non-drive side crank will secure itself
    on to the bottom bracket. Should be interesting to see how these
    perform.

    The single appears to be an ISIS interface, basically a multifaceted
    square taper attached with a press fit. Are you sure the spindle is
    permanently part of the left crank? I don't see what holds the right
    crank on other than an axial ISIS attachment bolt. Other than that I
    see nothing new.

    Jobst Brandt

  19. Thomas Hood said:
    Quoted message said:
    Quoted message said:

    I didn't look at the advertising material, but I think that one
    problem Campagnolo was trying to solve has to do with the loose
    fit between the inner bearing races and the spindle on Shimano
    cranks which, according to some, causes wear on the spindle.
    Campagnolo has bearings that are press fit on to the spindle. I
    have an Ultegra that seems to be doing fine so far.

    But are you goofy footed?

    Quoted message said:
    Quoted message said:

    As I have mentioned in earlier discussion about BB design, it's a huge
    can of worms and I don't see an easy solution to the bearing problem
    although I believe the crank attachment that Shimano has is a clean
    one that should work reliably. Their outboard bearing can't be good
    considering that inboard cups have failed on the right side from
    fretting, fretting that has a red flag on it because it requires a
    left hand thread, the best indicator of micro-motion.

    Quoted message said:
    Quoted message said:

    The point you mention is another headache for which I see no solution
    with the present design. This is such a high load interface that a
    slip fit bearing has got to fret and leave rouge traces from wear. I
    haven't worked with this BB but just looking at it at InterBike gave
    me reason to stay clear of it, considering how many cranks and
    spindles have withered under my feet.

    Quoted message said:
    Quoted message said:

    We'll have to wait and see.

    Quoted message said:

    I'm surprised no-one has mentioned that 2008 will see the external
    bearing start to disappear.

    Shimano: http://preview.tinyurl.com/yth9j3
    Trek: http://www.trekbikes.com/madone/technology/efficiency/

    Quoted message said:

    The difference between the two systems is that the Trek 'drops' a
    bare bearing in, whereas the Shimano needs a 'press fit'. I'd be
    surprised if special tools were actually _needed_ to fit remove the
    Shimano effort though. I wonder what seals -- if any -- either
    system use.

    As I mentioned when the Shimano design was first shown, an aluminum
    outboard bearing cup is too weak to withstand fretting damage in its
    threads and keep a solid hold to the BB. One of my riding pals has
    one of these and it creaks with standing hill climbing... as expected.
    I came to my assessment because steel internal cups with English
    threading fret enough to erode BB threads to zero, the BB being softer
    steel than the right bearing cup.

    If internal steel cups experience failure, external aluminum cups
    cannot be reliable. Either their threads will fail or the cups will
    break off at the BB face. That's why I say, I have no easy solution
    to the bearing problem although the crank attachment seems to be well
    taken care of. As you see, Shimano realized that bearings need a
    press fit or they will fret themselves into a loose fit.

    If these guys would only test their stuff on real riders before going
    to market, we could be spared the task of field testing at our
    expense. At least Campagnolo replaced failed parts in the days of
    Tullio.

    Jobst Brandt

  20. Quoted message said:
    Thomas Hood said:
    Quoted message said:

    > I didn't look at the advertising material, but I think that one
    > problem Campagnolo was trying to solve has to do with the loose
    > fit between the inner bearing races and the spindle on Shimano
    > cranks which, according to some, causes wear on the spindle.
    > Campagnolo has bearings that are press fit on to the spindle. I
    > have an Ultegra that seems to be doing fine so far.

    But are you goofy footed?

    Quoted message said:
    Quoted message said:

    As I have mentioned in earlier discussion about BB design, it's a huge
    can of worms and I don't see an easy solution to the bearing problem
    although I believe the crank attachment that Shimano has is a clean
    one that should work reliably. Their outboard bearing can't be good
    considering that inboard cups have failed on the right side from
    fretting, fretting that has a red flag on it because it requires a
    left hand thread, the best indicator of micro-motion.

    Quoted message said:
    Quoted message said:

    The point you mention is another headache for which I see no solution
    with the present design. This is such a high load interface that a
    slip fit bearing has got to fret and leave rouge traces from wear. I
    haven't worked with this BB but just looking at it at InterBike gave
    me reason to stay clear of it, considering how many cranks and
    spindles have withered under my feet.

    Quoted message said:
    Quoted message said:

    We'll have to wait and see.

    Quoted message said:

    I'm surprised no-one has mentioned that 2008 will see the external
    bearing start to disappear.

    Shimano: http://preview.tinyurl.com/yth9j3
    Trek: http://www.trekbikes.com/madone/technology/efficiency/

    Quoted message said:

    The difference between the two systems is that the Trek 'drops' a
    bare bearing in, whereas the Shimano needs a 'press fit'. I'd be
    surprised if special tools were actually _needed_ to fit remove the
    Shimano effort though. I wonder what seals -- if any -- either
    system use.

    As I mentioned when the Shimano design was first shown, an aluminum
    outboard bearing cup is too weak to withstand fretting damage in its
    threads and keep a solid hold to the BB. One of my riding pals has
    one of these and it creaks with standing hill climbing... as expected.
    I came to my assessment because steel internal cups with English
    threading fret enough to erode BB threads to zero, the BB being softer
    steel than the right bearing cup.

    If internal steel cups experience failure, external aluminum cups
    cannot be reliable. Either their threads will fail or the cups will
    break off at the BB face. That's why I say, I have no easy solution
    to the bearing problem although the crank attachment seems to be well
    taken care of. As you see, Shimano realized that bearings need a
    press fit or they will fret themselves into a loose fit.

    If these guys would only test their stuff on real riders before going
    to market, we could be spared the task of field testing at our
    expense. At least Campagnolo replaced failed parts in the days of
    Tullio.

    fud.

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