Geometry exercise

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
 http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

isn't that just basically an early model GT?

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
 http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

Should entries be mailed to:

Carl Fogel
309 Grace Ave.
Pueblo, CO
81004-1031

Or is that a phony return address you use when you send out nasty
snail mails?

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

Christ Carl, do you have to pick on that poor Andre with *every* *single*
*post*?

Scott said:

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
 http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

isn't that just basically an early model GT?

Dear Scott,

For all I know, there may be a modern GT model that looks somewhat
similar.

Some leaf-spring members may be involved in the 1899 patent, but
there's no damping or coil springs.

Plenty of pre-1900 bikes had front and rear suspension with leaf
springs, coil springs, and air-compression units, but damping wasn't
usually a feature.

Here's a scan of a gorgeous photo in Pryor Dodge's "The Bicycle" of an
1887 Whippet Spring-Frame Dwarf Safety Roadster:
http://i25.tinypic.com/vn1her.jpg

Left-click on the lower right for full-size in explorer. Take your
time figuring out which frame parts moved which way. The rear spoon
brake is tricky, and the fork-stem is just plain weird.

Basically, the top-tube and seat-tube and bottom-bracket bob up and
down in the long main frame member against the long coil spring.
Various hinge-joints take care of the details.

It's a bit closer to some kinds of modern mountain bike suspension,
but the spring is used in extension, not compression, and there's no
damping cylinder.

Nice dangling mounting pedal at the rear axle and coasting pegs on the
fork.

Alas, Dodge says that the color in the restored bike "is not in
keeping with the period." Otherwise, Jobst would be tempted to order
one as a spare in case his famous yellow-frame needs work.

Here's the Whippet in Sharp's "Bicycles & Tricycles", figure 277, page
down for text:

http://books.google.com/books?id=gFMN3-srupsC&printsec=frontcover&dq=inauthor:archibald+inauthor:sharp&as_brr=1&ei=qK8vR5ezL4GktAPMvqiwCQ#PPA296,M1

The black-and-white diagram doesn't do justice to the strange bike.

The Whippet's suspension dealt with the obvious problem of riding a
hard-tire safety on bad roads. Old bikes also had massive spring-seat
arrangements.

Dunlop's inflatable tire arrived in 1889 and soon put an end to the
more exotic suspension designs, but suspension survived in less
bizarre forms because it was useful on bad roads.

Here's a photo with detailed text about a ~1900 Pierce shaft-drive
with coil rear and spring-leaf front suspension:
http://americanhistory.si.edu/ONTHEMOVE/collection/object_299.html

If you didn't know and didn't look closely, you'd wouldn't notice the
modest suspension.

Cheers,

Carl Fogel

Quoted message said:

Christ Carl, do you have to pick on that poor Andre with *every* *single*
*post*?

Am I the only person who just doesn't get it? There's a joke somewhere...
there must be...

The only thing really worthwhile to come out of all of this is that I'm
thinking I can ID the "MI5" guy.

--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA

"_" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

Christ Carl, do you have to pick on that poor Andre with *every* *single*
*post*?

I do not see three triangles sharing a common side, not do I think it is
possible for three coplanar triangles to share a common side. So, I'm with
Mike J.

Leo Lichtman said:

I do not see three triangles sharing a common side, nor do I think it is
possible for three coplanar triangles to share a common side.

Dear Leo,

Think three-dimensional, not coplanar.

A traditional double-diamond frame is really a triple-diamond.

First, there's the front triangle.

True, the steering tube makes it technically a quadrilateral, but that
tube (particularly on modern bikes) is so short that it's a front
triangle to a first approximation.

Then there are the left and right rear triangles.

All three triangles share the common side of the seat post.
Technically, none of them are coplanar.

And--oops!--I should have written "curve the seatstays" instead of
carelessly writing "curve the chainstays."

Cheers,

Carl Fogel

Leo Lichtman said:

I do not see three triangles sharing a common side, not do I think it is
possible for three coplanar triangles to share a common side.

Of couse they can. You just need at least one to be "inside" one of the
others.

"_" <[email hidden]> wrote: Of couse they can.
You just need at least one to be "inside" one of the others.
^^^^^^^^^^^^^^^^^^^^^^
Of course. Blush. (Carl's response: 'They are not coplanar' is more
relevant.)

Ozark Bicycle said:

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

Should entries be mailed to:

Carl Fogel
309 Grace Ave.
Pueblo, CO
81004-1031

Or is that a phony return address you use when you send out nasty
snail mails?

The owner of that address can be verified in a couple of minutes if one
knows where to look.

--
Tom Sherman - Holstein-Friesland Bovinia
"And never forget, life ultimately makes failures of all people."
- A. Derleth

Mike Jacoubowsky said:

Quoted message said:

Christ Carl, do you have to pick on that poor Andre with *every* *single*
*post*?

Am I the only person who just doesn't get it? There's a joke somewhere...
there must be...

The only thing really worthwhile to come out of all of this is that I'm
thinking I can ID the "MI5" guy.

See <http://en.wikipedia.org/wiki/MI-5_Persecution>.

--
Tom Sherman - Holstein-Friesland Bovinia
"And never forget, life ultimately makes failures of all people."
- A. Derleth

On Jan 28, 9:12 pm, Tom Sherman <[email hidden]>

Quoted message said:

Ozark Bicycle said:

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
 http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

Quoted message said:

Quoted message said:

For extra credit, curve the chainstays.

Quoted message said:

Quoted message said:

Cheers,

Quoted message said:

Quoted message said:

Carl Fogel

Quoted message said:

Should entries be mailed to:

Quoted message said:

Carl Fogel
309 Grace Ave.
Pueblo, CO
81004-1031

Quoted message said:

Or is that a phony return address you use when you send out nasty
snail mails?

Quoted message said:

The owner of that address can be verified in a couple of minutes if one
knows where to look.

Do not tarry!

Ozark Bicycle said:

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
 http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

Should entries be mailed to:

Carl Fogel
309 Grace Ave.
Pueblo, CO
81004-1031

Ozark, I live at 165 West 83rd Street in New York City. Come to see
me. Let me know when you'll be in NYC. You'd said you would be
visiting some time, then cancelled that trip. If you're passing
through or visiting, let me know. Depending on the timing I can meet
you near where you will be.

JT

Hmm. Must be an Alex Moulten design ;-3)

- -
Compliments of:
"Your Friendly Neighborhood Wheelman"

If you want to E-mail me use:
ChrisZCorner "at" webtv "dot" net

My website:
http://geocities.com/czcorner

Quoted message said:

Given three triangles sharing a single common side B in a bicycle
frame, draw five unexpected new tubes:
http://www.google.com/patents?id=SugoAAAAEBAJ&pg=PP1&dq=d31448

For extra credit, curve the chainstays.

Cheers,

Carl Fogel

A slightly earlier but clearer (?) vision of almost the same frame by
the same inventor:
http://www.google.com/patents?id=gL8oAAAAEBAJ&pg=PP1&dq=d29944

Cheers,

Carl Fogel

On Tue, 29 Jan 2008 07:23:01 -0500, [email hidden]

(It's Chris) said:

Hmm. Must be an Alex Moulton design ;-3)

- -
Compliments of:
"Your Friendly Neighborhood Wheelman"

If you want to E-mail me use:
ChrisZCorner "at" webtv "dot" net

My website:
http://geocities.com/czcorner

Dear Chris,

You say that you want an early oddball bicycle frame with elastomer
suspension?

Here you are:
http://www.google.com/patents?id=E_o-AAAAEBAJ&pg=PA23&dq=546668

The wheels are too big, but it's got the seeds of a Moulton.

Cheers,

Carl Fogel