Difference between mountain and road threadless stems?

Discussion in 'Cycling Equipment' started by res09c5t, Apr 16, 2004.

  1. res09c5t

    res09c5t Guest

    Hi,
    I've been looking at some of the catalogs and see that the threadless stems
    are differentiated as road or mountain stems. Is there any real difference?
    I'm only familiar with the road world. The steerer should be a standard 1"
    or 1 1/8". Are the bars generally 26.0 on the mountain stems?

    I'm looking for something that provides the extra rise that some mountain
    stems provide.

    Thanks!
    Lyle
     
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  2. res09c5t wrote:

    > I've been looking at some of the catalogs and see that the threadless stems
    > are differentiated as road or mountain stems. Is there any real difference?


    It's basically marketing.

    > I'm only familiar with the road world. The steerer should be a standard 1"
    > or 1 1/8". Are the bars generally 26.0 on the mountain stems?


    No, most bars are ISO standard size, 1" (25.4 mm) but many drop bars are
    the Italian 26.0 size.

    Two bolt "pop-top" stems are pretty forgiving about this, and can
    generally be interchanged between the two standars.

    Sheldon "Stems Don't Care What Kind Of Surface You Ride On" Brown
    +-----------------------------------------------+
    | I’m appearing as Preposteros in |
    | Gilbert & Sullivan's Thespis at M.I.T. |
    | April 9-10,15-17 http://web.mit.edu/gsp/www |
    | http://sheldonbrown.com/music.html |
    | Photos: http://sheldonbrown.org/g-s/thespis |
    +-----------------------------------------------+
    Harris Cyclery, West Newton, Massachusetts
    Phone 617-244-9772 FAX 617-244-1041
    http://harriscyclery.com
    Hard-to-find parts shipped Worldwide
    http://captainbike.com http://sheldonbrown.com
     
  3. <snip>
    >It's basically marketing.


    >Sheldon "Stems Don't Care What Kind
    >Of Surface You Ride On" Brown

    </snip>

    Actually, Mr. Brown, there may be a difference. I'm just guessing, but
    wouldn't a stem designed for off road use need to be more rugged? and
    since it doesn't need the extra toughness, wouldn't a road stem favor
    lightness over strength?

    Or am I once again imagining a perfect world that cannot possibly exist
    in reality? ;-3)

    - -

    "May you have the wind at your back.
    And a really low gear for the hills!"

    Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

    Chris'Z Corner
    http://www.geocities.com/czcorner
     
  4. buffedupboy

    buffedupboy Guest

    Hi if I am not mistaken.... MTB stem clamps are 25.4mm dia. Roadbike
    quill stems used to be the same but when changed to threadless system
    went to a 26.0mm dia. clamp. They are now doing 31.8mm dia clamps which
    are indicated as oversized.

    Regarding marketing BS or not, I don't want to comment. Regarding ISO
    standards, I don't know how to comment.

    Regards, Sean



    --
     
  5. An anonymous poster wrote:

    > Hi if I am not mistaken.... MTB stem clamps are 25.4mm dia.=20


    Yes, that is the ISO standard size for all types of bicycles, a.k.a. 1 in=
    ch.

    > Roadbike
    > quill stems used to be the same but when changed to threadless system
    > went to a 26.0mm dia. clamp.=20


    No, there's no connection with threadless, that has to do with the other =

    end of the stem, the way it fits on the fork.

    Both quill and threadless stems are readily available in both 25.4 and=20
    26 mm sizes. The selection is much better, however, in the ISO=20
    standard 25.4 size.

    Before the ISO standards were promulgated, there were a variety of=20
    national sizes for handlebar/stem clamps, and also some proprietary ones =

    used by specific manufacturers (Cinelli, Titan.)

    Because some Italian brands of stems and handlebars were popular for=20
    high-end road bikes, the Italian 26.0 mm standard is often used as a=20
    secondary size standard for drop handlebars, but most drop bars on the=20
    road are actually 25.4.

    > They are now doing 31.8mm dia clamps which are indicated as oversized.


    a.k.a. 1 1/8"

    Sheldon "Can't Kill Inch-based Standards" Brown
    +-----------------------------------------------+
    | I=92m appearing as Preposteros in |
    | Gilbert & Sullivan's Thespis at M.I.T. |
    | April 9-10,15-17 http://web.mit.edu/gsp/www |
    | http://sheldonbrown.com/music.html |
    | Photos: http://sheldonbrown.org/g-s/thespis |
    +-----------------------------------------------+
    Harris Cyclery, West Newton, Massachusetts
    Phone 617-244-9772 FAX 617-244-1041
    http://harriscyclery.com
    Hard-to-find parts shipped Worldwide
    http://captainbike.com http://sheldonbrown.com
     
  6. Sheldon Brown <[email protected]> wrote:
    > Because some Italian brands of stems and handlebars were popular
    > for high-end road bikes, the Italian 26.0 mm standard is often
    > used as a secondary size standard for drop handlebars, but most
    > drop bars on the road are actually 25.4.


    Is that really the case in the US? At least here in continental
    Europe 25,4m is not common for drop bars.


    --
    MfG/Best regards
    helmut springer
     
  7. Chris Zacho "The Wheelman" <[email protected]> wrote:
    > Actually, Mr. Brown, there may be a difference. I'm just guessing,
    > but wouldn't a stem designed for off road use need to be more
    > rugged? and since it doesn't need the extra toughness, wouldn't a


    Visualize the road cyclist climbing and sprinting hard, hitting a
    pothole at hight speed with high pressure tires from time to time.

    --
    MfG/Best regards
    helmut springer
     
  8. Rick Onanian

    Rick Onanian Guest

    On Sat, 17 Apr 2004 10:52:25 -0400, [email protected] (Chris
    Zacho "The Wheelman") wrote:
    >>It's basically marketing.
    >>Sheldon "Stems Don't Care What Kind
    >>Of Surface You Ride On" Brown

    >
    >Actually, Mr. Brown, there may be a difference. I'm just guessing, but
    >wouldn't a stem designed for off road use need to be more rugged? and
    >since it doesn't need the extra toughness, wouldn't a road stem favor
    >lightness over strength?


    According to Nashbar (see below), that's all true; but it doesn't
    make Sheldon wrong. The stem still doesn't care, and the issue is
    still _basically_ marketing. There's a little bit of weight savings:
    Easton EA70XC off-road stem: 135gm
    Easton EA70 road stem: 130gm
    Same manufacturer, on and off road variation of same model, 5 gram
    difference.

    $20 ITM road stem: 193gm (120mm)
    $20 Nashbar off-road stem: 178gm (105mm)
    Given the length difference, probably almost exactly the same at
    equal length.
    --
    Rick Onanian
     
  9. > > They are now doing 31.8mm dia clamps which are indicated
    > > as oversized.


    "Sheldon Brown" <[email protected]> wrote:

    > a.k.a. 1 1/8"


    Trust an American fraction to be twice the size of a British one.

    :eek:/

    James Thomson
     
  10. DRS

    DRS Guest

    Sheldon Brown <[email protected]> wrote in message
    [email protected]

    [...]

    > Sheldon "Can't Kill Inch-based Standards" Brown


    Yes, even when it sounds longer in metric.

    --

    A: Top-posters.
    Q: What is the most annoying thing on Usenet?
     
  11. dianne_1234

    dianne_1234 Guest

    Sheldon Brown <[email protected]> wrote in message news:<[email protected]>...
    > res09c5t wrote:
    >
    > > I've been looking at some of the catalogs and see that the threadless stems
    > > are differentiated as road or mountain stems. Is there any real difference?

    >
    > It's basically marketing.
    >
    > Sheldon "Stems Don't Care What Kind Of Surface You Ride On" Brown


    There are different test standards for racing and mountain bikes, and
    the loads differ. Whether the stems we buy are actually different in
    practice I don't know.

    Here's one mountain standard:
    http://web.uni.com/stampa/articoli_2003/mount_bicycles.pdf

    Maybe someone can find the racing bike standard, I couldn't.
     
  12. Ed Cory

    Ed Cory Guest

    Sheldon Brown <[email protected]> wrote in message news:<[email protected]>...
    <SNIP>
    >
    > > They are now doing 31.8mm dia clamps which are indicated as oversized.

    >
    > a.k.a. 1 1/8"
    >


    1 1/8" is about 28.6mm, not 31.8mm.

    31.8mm is much closer to 1 1/4".

    Ed
     
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