J
Joe Riel
Guest
jim beam <[email protected]> writes:
> Tim McNamara wrote:
> <snip>
>> FWIW my logic goes:
>> A. A disk brake can cause an ejection force on the front wheel.
>> B. There is no need for an ejection force, as forks can easily be
>> designed to eliminate it.
>> C. Forks should be redesigned to eliminate the ejection force.
>> The background assumption, of course, is that wheel ejection is a
>> bad thing and is to be avoided.
>
> the logical flaw is amazing. illustration:
>
> 1. use of a bridge causes a collapsing force on it.
> 2. there is no need for a collapsing force.
> 3. bridges should not be used.
> the real consideration of course is how great the collapsing force is
> in relation to capacity, not whether a collapsing force exists.
> repeated failure to recognize that fundamental point is a truly
> extraordinary mental block.
Suppose the bridge were designed so that the entire structure depended
on the clamping of a quick-release to hold it together. Traffic on
the bridge would apply a force to the QR that tended to eject it,
however, if clamped with the "speced" tightness, the serrations in the
faces would provide a 3x margin to the rated load of the bridge.
Assume the QR was inspected regularly by a trained operator and access
by others was not an issue. Would anyone consider that a reasonable
design? What if the operator had the training and dedication of a
typical mountain bike rider (with respect to the proper operation of
QRs)?
--
Joe Riel
> Tim McNamara wrote:
> <snip>
>> FWIW my logic goes:
>> A. A disk brake can cause an ejection force on the front wheel.
>> B. There is no need for an ejection force, as forks can easily be
>> designed to eliminate it.
>> C. Forks should be redesigned to eliminate the ejection force.
>> The background assumption, of course, is that wheel ejection is a
>> bad thing and is to be avoided.
>
> the logical flaw is amazing. illustration:
>
> 1. use of a bridge causes a collapsing force on it.
> 2. there is no need for a collapsing force.
> 3. bridges should not be used.
> the real consideration of course is how great the collapsing force is
> in relation to capacity, not whether a collapsing force exists.
> repeated failure to recognize that fundamental point is a truly
> extraordinary mental block.
Suppose the bridge were designed so that the entire structure depended
on the clamping of a quick-release to hold it together. Traffic on
the bridge would apply a force to the QR that tended to eject it,
however, if clamped with the "speced" tightness, the serrations in the
faces would provide a 3x margin to the rated load of the bridge.
Assume the QR was inspected regularly by a trained operator and access
by others was not an issue. Would anyone consider that a reasonable
design? What if the operator had the training and dedication of a
typical mountain bike rider (with respect to the proper operation of
QRs)?
--
Joe Riel