Brakeless gear hubs

Discussion in 'Cycling Equipment' started by Adam Rush, May 9, 2004.

  1. Adam Rush

    Adam Rush Guest

    When a gear hub is manufactured without a coaster or drum brake, what
    is it usually made to do when back-pedalled? Does it freewheel for
    all eternity or does it go a few rotations before going no further?
     
    Tags:


  2. Adam Rush wrote:
    > When a gear hub is manufactured without a coaster or drum brake, what
    > is it usually made to do when back-pedalled? Does it freewheel for
    > all eternity or does it go a few rotations before going no further?


    Usually freewheels for all eternity; at least, that's what
    Sturmey-Archer ones do.
     
  3. Werehatrack

    Werehatrack Guest

    On 9 May 2004 05:11:02 -0700, [email protected] (Adam Rush) may have
    said:

    >When a gear hub is manufactured without a coaster or drum brake, what
    >is it usually made to do when back-pedalled? Does it freewheel for
    >all eternity or does it go a few rotations before going no further?


    All of the Sturmey-Archer, Shimano and Sachs non-coaster gear hubs of
    my experience simply freewheel if back-pedalled. If there's no
    coaster brake, the freewheeling sprocket on the hub should not care
    whether the speed mismatch is due to backpedalling or not pedalling;
    it will simply ratchet freely in either case.

    --
    My email address is antispammed; pull WEEDS if replying via e-mail.
    Typoes are not a bug, they're a feature.
    Words processed in a facility that contains nuts.
     
  4. Adam Rush

    Adam Rush Guest

    Zog The Undeniable <[email protected]> wrote in message news:<[email protected]>...
    > Adam Rush wrote:
    > > When a gear hub is manufactured without a coaster or drum brake, what
    > > is it usually made to do when back-pedalled? Does it freewheel for
    > > all eternity or does it go a few rotations before going no further?

    >
    > Usually freewheels for all eternity; at least, that's what
    > Sturmey-Archer ones do.


    Where I live, "Sturmey-Arch" is translated to "Sachs." Anybody with
    info on the Dreigang?
     
  5. A Muzi

    A Muzi Guest

    Adam Rush wrote:
    > When a gear hub is manufactured without a coaster or drum brake, what
    > is it usually made to do when back-pedalled? Does it freewheel for
    > all eternity or does it go a few rotations before going no further?


    Single and multiple speed hubs with no backpedal brake just
    coast. You may indeed backpedal forever just as you could
    with a Record cassette hub. Or a freewheel hub. Or a Profile
    Racing flatland single speed hub.
    Hubs which allow coasting by one means or another
    incorporate a one-way device which engages the hub shell
    when pedaling forward. That mechanism, usually a pawl in a
    ratchet ring, just does not engage the other direction

    Coaster ( backpedal) brake hubs have two mechanisms, one to
    engage and drive the hub shell (for example, a clutch
    that's pulled tight against the hub shell or a series of
    rollers which run up ramps and jam against the hub shell)
    and another to press a stationary component against a moving
    one to provide braking ( either an expanding cylinder
    against the hub shell or a series of discs engaged
    alternately to the hub and axle which all press together or
    some such). The default position, achieved by turning the
    hub but not one's pedals, is disengagement of both mechanisms.

    Andrew Muzi
    www.yellowjersey.org
    Open every day since 1 April, 1971
     
Loading...
Similar Threads - Brakeless
  1. oam3292
    Replies:
    17
    Views:
    1,503
  2. phil2
    Replies:
    2
    Views:
    488
Loading...