MB Disc brakes

Discussion in 'Cycling Equipment' started by The Airman, Jul 16, 2005.

  1. The Airman

    The Airman Guest

    I was thinking of getting a replacement mountain equipped with front and
    rear disc brakes, but someone told me some time back about some safety
    issue with disc brakes and front wheels falling off?

    Is this correct? Is there a safety issue?

    Are disc brakes that much better calipers?

    Thanks
     
    Tags:


  2. Robin Hubert

    Robin Hubert Guest

    The Airman wrote:
    > I was thinking of getting a replacement mountain equipped with front and
    > rear disc brakes, but someone told me some time back about some safety
    > issue with disc brakes and front wheels falling off?
    >
    > Is this correct? Is there a safety issue?
    >
    > Are disc brakes that much better calipers?
    >
    > Thanks
    >
    >


    Try this:

    http://groups-beta.google.com/groups?hl=en&q=disc+brakes+annan


    Robin Hyooobert
     
  3. jim beam

    jim beam Guest

    The Airman wrote:
    > I was thinking of getting a replacement mountain equipped with front and
    > rear disc brakes, but someone told me some time back about some safety
    > issue with disc brakes and front wheels falling off?
    >
    > Is this correct? Is there a safety issue?
    >
    > Are disc brakes that much better calipers?
    >
    > Thanks
    >
    >

    if you ride in rain or mud, disk brakes are /way/ better than rim
    brakes. hydraulic disk brakes in particular offer very good modulation
    & ease of use, with very little, if any, fade.

    regarding "the safety issue", it's been discussed at length on this
    group many times. bottom line is that the "safety issue" scare is based
    on a flawed assumption of the force necessary to cause slippage of an
    axle in a fork as a result of disk braking forces. because that
    assumption is flawed, it "appears" that forces generated by braking can
    eject a front axle from a fork. reality however is that the force
    necessary to cause slipage is many times that assumed in the scare,
    and that's /before/ you take the fork's "lawyer lips" into account.
    hence, the real math accords with what we see in practice: wheels do not
    eject.

    to be prudent, there is some benefit in using a front skewer that is
    known to produce consistently reliable clamping such as the closed cam
    shimano & campy type skewers, but the bottom line is that unless you
    have outright skewer failure or don't follow manufacturer instructions
    on mounting the wheel, you'll have no problems whatsoever.
     
  4. "The Airman" <[email protected]> wrote in message
    news:[email protected]
    >I was thinking of getting a replacement mountain equipped with front and
    > rear disc brakes, but someone told me some time back about some safety
    > issue with disc brakes and front wheels falling off?
    >
    > Is this correct? Is there a safety issue?
    >
    > Are disc brakes that much better calipers?
    >
    > Thanks




    Been using disks for 3 years. Two different systems on three different
    forks, two frames.

    AFAIK, my wheels have not detached from the fork without me wanting then
    too!

    Ask who has returned to caliper brakes after using disks?

    --
    DTW .../\.../\.../\...

    I've spent most of my money on mountain biking and windsurfing.
    The rest, I've just wasted.
     
  5. Per The Airman:
    > and front wheels falling off?
    >
    >Is this correct? Is there a safety issue?


    There have been numerous and heated threads about the wheel ejection thing.
    My belief is that the lawyer lips make it moot.


    One other thing, though: If you're running mechs, be sure to trim the tail of
    the cable reasonably cose - like a half inch. Supposedly if the tail is long
    enough, it can jam in the brake with catestrophic results if it's the front
    brake.


    Are they "better"?

    Horses for courses. Depends on what you need are.

    For the front brake, I wouldn't want anything else but my Hope C2.

    For the rear brake, if my calf didn't bang on it all the time I might be using a
    v-brake. As it is, I'm happy with an Avid mech.
    --
    PeteCresswell
     
  6. Mykal

    Mykal Guest

    "The Airman" <[email protected]> wrote in message
    news:[email protected]
    > I was thinking of getting a replacement mountain equipped with front

    and
    > rear disc brakes, but someone told me some time back about some

    safety
    > issue with disc brakes and front wheels falling off?
    >
    > Is this correct? Is there a safety issue?
    >
    > Are disc brakes that much better calipers?
    >
    > Thanks
    >


    IMO:

    1) Don't use any of the "mechanical" disc brakes. They are all crap
    because they require the rotor to bend with every actuation. Thus,
    with the mech disc brakes, an evenly distributed friction over the
    braking surface is impossible and damage by proper use is normal.



    2) If using QRs, use closed cam QR. Open-cam QR requires a grossly
    inconsistent amount of actuation force to attain clamping force
    adequate for front wheel with disc brake. As a result, what may be
    good for one wheel installation may allow the wheel to eject after
    another installation.



    3) Front wheel ejections caused by disc brakes are being prevented by
    the retaining lips on fork dropouts. That is, catastrophic
    consequences are averted because the axle is kept in the dropouts even
    after the QR mechanism has failed. If bikes didn't come with the
    so-called lawyer tabs on the dropouts, I think we'd be seeing a lot of
    serious injuries caused by the now well-published design flaw that you
    have referred to.



    Just my 2 cents,

    Mykal
     
  7. "D T W .../\..." <[email protected]> wrote in message
    news:[email protected]
    > "The Airman" <[email protected]> wrote in message
    > news:[email protected]
    >>I was thinking of getting a replacement mountain equipped with front and
    >> rear disc brakes, but someone told me some time back about some safety
    >> issue with disc brakes and front wheels falling off?
    >>
    >> Is this correct? Is there a safety issue?
    >>
    >> Are disc brakes that much better calipers?
    >>
    >> Thanks

    >
    >
    >
    > Been using disks for 3 years. Two different systems on three different
    > forks, two frames.
    >
    > AFAIK, my wheels have not detached from the fork without me wanting then
    > too!
    >
    > Ask who has returned to caliper brakes after using disks?


    I have, to reap the weight savings on an XC bike.

    --
    Phil, Squid-in-Training
     
  8. Werehatrack

    Werehatrack Guest

    On Sat, 16 Jul 2005 14:26:59 GMT, "The Airman" <[email protected]>
    wrote:

    >I was thinking of getting a replacement mountain equipped with front and
    >rear disc brakes, but someone told me some time back about some safety
    >issue with disc brakes and front wheels falling off?
    >
    >Is this correct? Is there a safety issue?
    >
    >Are disc brakes that much better calipers?


    Front wheel ejection may happen in certain circumstances. Some
    incidents have been traced to improper skewer adjustment, but others
    have no such simple explanation. All such events are apparently quite
    rare, however. Although the issue has been brought to the attention
    of the USCPSC, no need had been established for a recall linked to
    disk brake wheel ejection of the last time I checked.

    As for whether disk brakes are "better", the answer is situational.
    If you do a lot of riding in wet areas, disc brakes may be more useful
    due to their greater immunity to problems in that sort of usage. Some
    rim brakes tend to lose effectiveness when wet, and some tend to
    become rim eaters when wet and/or dirty. In dry, clean conditions, a
    disc brake may still be an advantage if you make a lot of long decents
    in which you must ride the brakes hard enough that tire overheating
    could be an issue. If neither of these is an issue for you, then
    there may not be a strong reason for choosing discs. Some people just
    like the way they work (from an operational feel standpoint) better
    than rim brakes; that's a personal preference issue rather than a
    technical performance matter, though.

    Rear disc brakes are widely viewed as a waste of money, however, even
    when a front disc is deemed useful. YMMV. I've had both, and I find
    rear discs to offer no significant advantage. That's just my
    preference; others disagree, and have their own reasons.
    --
    Typoes are a feature, not a bug.
    Some gardening required to reply via email.
    Words processed in a facility that contains nuts.
     
  9. jtaylor

    jtaylor Guest

    "Werehatrack" <[email protected]> wrote in message
    news:[email protected]
    > As for whether disk brakes are "better", the answer is situational.
    > If you do a lot of riding in wet areas, disc brakes may be more useful
    > due to their greater immunity to problems in that sort of usage. Some
    > rim brakes tend to lose effectiveness when wet, and some tend to
    > become rim eaters when wet and/or dirty. In dry, clean conditions, a
    > disc brake may still be an advantage if you make a lot of long decents
    > in which you must ride the brakes hard enough that tire overheating
    > could be an issue. If neither of these is an issue for you, then
    > there may not be a strong reason for choosing discs. Some people just
    > like the way they work (from an operational feel standpoint) better
    > than rim brakes; that's a personal preference issue rather than a
    > technical performance matter, though.
    >


    Disks do not distort the rim, nor are they as likely to have variations in
    braking force due to variations of the braking surface; when steering _and_
    braking on a hard surface it is possible that those two factors will permit
    the rider to come closer to the limit of traction.
     
  10. Werehatrack

    Werehatrack Guest

    On Sun, 17 Jul 2005 09:16:58 -0300, "jtaylor"
    <[email protected]> wrote:

    >Disks do not distort the rim,


    Good rim brakes don't, either, in most cases.

    >nor are they as likely to have variations in
    >braking force due to variations of the braking surface; when steering _and_
    >braking on a hard surface it is possible that those two factors will permit
    >the rider to come closer to the limit of traction.


    From personal experience, some disks tend to warp, and some develop
    irregular wear and/or irregular surfaces, all of which can result in
    brake pulsation every bit as bad as that of a rim that's not true or
    is worn unevenly...and not all disk brakes are even as effective as an
    average rim brake in dry conditions. While a *good* disc brake will
    be better than a *poor* rim brake, the same holds true in the other
    direction. There mere fact that some disc brake systems work well
    does not mean that they're all that good, and the fact that some rim
    brakes exhibit problems does not mean that they all will. Intelligent
    choices are based on individual characteristics and needs, not blanket
    assumptions.
    --
    Typoes are a feature, not a bug.
    Some gardening required to reply via email.
    Words processed in a facility that contains nuts.
     
  11. Per D T W .../\...:
    >Ask who has returned to caliper brakes after using disks?


    I tried to for the rear brake, but my calf kept banging on the v-brake.
    --
    PeteCresswell
     
Loading...
Loading...