if you wanted maximum braking, where would you sit?

(Carl Fogel) wrote in message . com...


Dear Robert,

It turns out that Colorado 226 isn't listed on the
Colorado Highway site that I mentioned--odd. From
Georgetown at around 8,470, it's supposed to be
about 12 miles to the top of Guanella Pass at
11,669--a climb of 3200 feet in 12 miles, or an
average grade of 5%. I wouldn't be surprised if
this road, paved about half-way, gets much steeper
toward the top after the pavement ends.


Carl, this number is demoralizingly low, considering how this hill has
brutalized me with decisive bitchslaps each time I have ridden it..
But then I was heartened to learn that Guanella is considered an Hors
Categorie climb on the Eurofreak scale and is the toughest hill among
many in the legendary Saturn Classic road race from Boulder to
Breckenridge. By comparison, Hoosier Pass is Category 2, as is
Kenosha. Freelancing a bit, we can extrapolate that Red Mountain,
Slumgullion, Independence, and perhaps Wolf Creek Passes would be
Category 1 climbs. These four also happen to be the most beautiful and
spectacular *paved* passes in Colorado, IMO.

Imogene and Mosquito passes are, as you point out,
4wd-type single-car dirt roads. Both are long-abandoned
wagon and stage-coach tracks.

Imogene Pass is supposed to gain about 4,350 feet
in about 7 miles, an average grade of 11.7%


This hill gave me Post Traumatic Stress Disorder.


Mosquito Pass has so far defied my efforts to find
desperately important statistics.

Mosquito Pass defied my efforts to get up it without puking.

Grades are often tricky to quantify because the initial
part of the climb is usually gentler--an average 5%
grade is one thing, while the upper part of Guanella
Pass is probably quite another. However, most of the
Colorado passes that I listed tend to be railroad
and modern-style highway cuts with unusually steady
grades. The older and often abandoned two-rut passes
used by wagons during mining days are more haphazard,
but horses hauled heavily-laden wagons and coaches up
them.


Yes, the wide highway-style passes (Monarch, Kenosha, Hoosier,
Berthoud to an extent, etc. cannot compete with the less tame ones in
my book. But the narrow paved passes can also be tricky for cycling.
Drivers are always banging their cars against the side of the mountain
coming down Independence into Aspen. It's very narrow. Same with Red
Mountain into Ouray. There are opportunities for carless paved climbs
however. The bike path over Vail Pass is a nice ride. Also, one can
sneak around the gate and ride the Mt. Evans road in the late fall
after it is closed for the year.

Here's an example of 1898 Colorado modesty:

http://www.livgenmi.com/1898denver~switzerland.htm

The pictures load slowly, but the text leaves no doubt
that the Centennial State has always been shy and
retiring--take that, Switzerland!

Carl Fogel

Colorado and Switzerland are both excellent. Swiss trails are steeper;
they don't have switchback technology there. Switzerland has many more
snails, and slightly more Nazis.

Robert

On Saturday, January 10, 2004 at 7:02:33 AM UTC-8, Sheldon Brown wrote:
Tim McNamara wrote:

Under "maximum braking" the front wheel stops dead, the bicycle
flips, and the rider is ejected. If you are talking about keeping
both wheels on the ground that is far less braking force than
maximum.

That can be circumvented. Build a bike that positions your center of
gravity below the front axle. You could lock the wheel up tight and
still not do an endo.

I replied in part:

It actually has nothing to do with the axle, since a locked-up wheel
doesn't rotate, so it effectively stops being a wheel.

The critical thing is the angle of a line drawn from the tire contact
patch to the center of mass of the bike-and-rider.

Douglas Landau wrote:

I think you are correct because the OP misstated the problem. In
reality however Tim M is correct. In practice, when we go over
the bars it is not [usually] because the front wheel stops and
the bike and rider pivot around the contact patch. More often
we go over the bars because the frame and fork and rider and rear
wheel pivot around the front axle.

'Fraid not. For that to happen, the front wheel would have to stop
moving forward, while the frame and fork did the endo. Such a scenario
would actually involve the front hub bearing reversing direction, so the
wheel would be rolling backward with respect to the frame. Where is
there a force that would cause the front wheel to rotate backwards?

If you build a bike like Tim says, you are right that it could
still endo around the contact patch. However, such a bike would
not endo around the front axle. I have seen riders endo after
dropping the front wheel in a pothole. Tim's bike would not do
that. The rider would come off the seat in an even more painful
way.

In a case where the front wheel is forcibly stopped by falling into a
deep pothole or hitting a high curb, it _is_ possible for the bike to
pivot around the front axle, but there's no way this can happen under
the influence of the brake alone.


It was actually Mr. Tezlaff's front wheel that I saw drop into a pothole, and he who went over the bars. And I -assumed- that the bike rotated around the front axle, of course, just for the fun of challenging Sheldon.

On Tuesday, November 17, 2015 at 2:33:00 PM UTC-5, Doug Landau wrote:
On Saturday, January 10, 2004 at 7:02:33 AM UTC-8, Sheldon Brown wrote:
Tim McNamara wrote:

Under "maximum braking" the front wheel stops dead, the bicycle
flips, and the rider is ejected. If you are talking about keeping
both wheels on the ground that is far less braking force than
maximum.

That can be circumvented. Build a bike that positions your center of
gravity below the front axle. You could lock the wheel up tight and
still not do an endo.

I replied in part:

It actually has nothing to do with the axle, since a locked-up wheel
doesn't rotate, so it effectively stops being a wheel.

The critical thing is the angle of a line drawn from the tire contact
patch to the center of mass of the bike-and-rider.

Douglas Landau wrote:

I think you are correct because the OP misstated the problem. In
reality however Tim M is correct. In practice, when we go over
the bars it is not [usually] because the front wheel stops and
the bike and rider pivot around the contact patch. More often
we go over the bars because the frame and fork and rider and rear
wheel pivot around the front axle.

'Fraid not. For that to happen, the front wheel would have to stop
moving forward, while the frame and fork did the endo. Such a scenario
would actually involve the front hub bearing reversing direction, so the
wheel would be rolling backward with respect to the frame. Where is
there a force that would cause the front wheel to rotate backwards?

If you build a bike like Tim says, you are right that it could
still endo around the contact patch. However, such a bike would
not endo around the front axle. I have seen riders endo after
dropping the front wheel in a pothole. Tim's bike would not do
that. The rider would come off the seat in an even more painful
way.

In a case where the front wheel is forcibly stopped by falling into a
deep pothole or hitting a high curb, it _is_ possible for the bike to
pivot around the front axle, but there's no way this can happen under
the influence of the brake alone.


It was actually Mr. Tezlaff's front wheel that I saw drop into a pothole, and he who went over the bars. And I -assumed- that the bike rotated around the front axle, of course, just for the fun of challenging Sheldon.

Why revive this TEN YEARS OLD thread especially that Sheldon's dead and can't reply?

Cheers

On Tuesday, November 17, 2015 at 6:19:16 PM UTC-7, Doug Landau wrote:
On Tuesday, November 17, 2015 at 5:03:15 PM UTC-8, wrote:
https://goo.gl/Bfy2oI

Those people are laying down not sitting

))))))))))))))

Ima primary participant, here choosing the adjectival spread of "occupying space as fixed object in danger'