Cycling & bikes - Ultimate low-spoke-count rear wheel

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Ultimate low-spoke-count rear wheel

wrote:
http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
http://www.gizmag.com/spokeless-bicy...icture/110818/
http://www.gizmag.com/spokeless-bicy...icture/110819/
http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

Those pedals better be held in with Loctite. Because they probably
didn't spend the money on a tandem front crank.

--
- Frank Krygowski

Ultimate low-spoke-count rear wheel

On Oct 2, 4:31*pm, Frank Krygowski wrote:
wrote:
http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
*http://www.gizmag.com/spokeless-bicy...icture/110818/
*http://www.gizmag.com/spokeless-bicy...icture/110819/
*http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

Those pedals better be held in with Loctite. *Because they probably
didn't spend the money on a tandem front crank.

--
- Frank Krygowski

There is such a thing as a pedal spanner. Stand on it to tighten the
pedal then bounce a little to crack it on full whack. It never shifts
from this installed position in either direction despite your
unfounded fears.

Ultimate low-spoke-count rear wheel

In article ,
wrote:

http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
http://www.gizmag.com/spokeless-bicy...icture/110818/
http://www.gizmag.com/spokeless-bicy...icture/110819/
http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

I do like the way they glued a toothed belt to the inside of the wheel
for drive purposes. That was ingenious. The rest of the design seems
like making your life difficult just for fun.

Ultimate low-spoke-count rear wheel

On Sun, 02 Oct 2011 11:31:18 -0400, Frank Krygowski
wrote:

wrote:
http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
http://www.gizmag.com/spokeless-bicy...icture/110818/
http://www.gizmag.com/spokeless-bicy...icture/110819/
http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

Those pedals better be held in with Loctite. Because they probably
didn't spend the money on a tandem front crank.

Dear Frank,

The "Shimano" on the crank is upside-down, so they must have used an
ordinary crank that was handy:
http://www.gizmag.com/spokeless-bicy...icture/110820/

There is indeed a reason why pedals come with left-hand and right-hand
threads, but this oddball probably won't be pedalled far enough to
reveal the problem.

Cheers,

Carl Fogel

Ultimate low-spoke-count rear wheel

On Oct 2, 7:00*pm, wrote:
On Sun, 02 Oct 2011 11:31:18 -0400, Frank Krygowski

wrote:
wrote:
http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
*http://www.gizmag.com/spokeless-bicy...icture/110818/
*http://www.gizmag.com/spokeless-bicy...icture/110819/
*http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

Those pedals better be held in with Loctite. *Because they probably
didn't spend the money on a tandem front crank.

Dear Frank,

The "Shimano" on the crank is upside-down, so they must have used an
ordinary crank that was handy:
*http://www.gizmag.com/spokeless-bicy...icture/110820/

There is indeed a reason why pedals come with left-hand and right-hand
threads, but this oddball probably won't be pedalled far enough to
reveal the problem.

Cheers,

Carl Fogel

It's for speed of assembly. With the bike held in the air by the seat
pin, the pedals are threaded on together by turning the cranks
backward. It's a simple single operation used to cut production
time. A pedal spanner is applied with the wheels on the ground and
cracked tight, leaving the cycle safe to operate. The direction of
thread is unimportant, a pedal may still come off if it is not cracked
tight. I have seen this happen with steel axles in steel cranks.

Ultimate low-spoke-count rear wheel

On Oct 2, 3:13*pm, thirty-six wrote:
On Oct 2, 7:00*pm, wrote:

On Sun, 02 Oct 2011 11:31:18 -0400, Frank Krygowski

wrote:
wrote:
http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
*http://www.gizmag.com/spokeless-bicy...icture/110818/
*http://www.gizmag.com/spokeless-bicy...icture/110819/
*http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

Those pedals better be held in with Loctite. *Because they probably
didn't spend the money on a tandem front crank.

Dear Frank,

The "Shimano" on the crank is upside-down, so they must have used an
ordinary crank that was handy:
*http://www.gizmag.com/spokeless-bicy...icture/110820/

There is indeed a reason why pedals come with left-hand and right-hand
threads, but this oddball probably won't be pedalled far enough to
reveal the problem.

Cheers,

Carl Fogel

It's for speed of assembly. *With the bike held in the air by the seat
pin, the pedals are threaded on together by turning the cranks
backward. *It's a simple single operation used to cut production
time. *A pedal spanner is applied with the wheels on the ground and
cracked tight, leaving the cycle safe to operate. *The direction of
thread is unimportant, a pedal may still come off if it is not cracked
tight. *I have seen this happen with steel axles in steel cranks.

Assembly speed? Maybe so, or at least that might be one consideration.
At what point does the chain get put on?

I've seen a Campy steel axle pedal come out of a Campy alu crank arm
in use-- a new pedal and crank, maybe 20 miles max into the first
ride, and the pedal was not, according to the post-accident
investigation, tightened "tight". It was a right-side pedal btw.

When I used to rent track bikes at Alkek Velodrome, one "overseer"
took me to task for using the leverage available in the pedal wrench.
Um, corrected later in the infield while supervision was supervising
elsewhere, thank you very much. I always just figured the pedal
spanner had an unusually long handle on it, compared to the other
"hand tools" for good reason. Only one of which "good reasons" was
getting tight pedals off g. After Reading Jobst, I would think that,
while a very tight pedal spindle might still fret a crank (arm) (g)
around the pedal eye, it should fret less than a looser one.
--D-y

Ultimate low-spoke-count rear wheel

On Oct 3, 10:55*am, " wrote:

Assembly speed? Maybe so, or at least that might be one consideration.

Dear D,

Reversed pedal threading has nothing to do with assembly speed.

"In 1900, the Wrights announced a 'bicycle pedal that can't come
unscrewed.' Pedals were mounted to the crank by threaded posts. On
early bicycles, both posts had standard right-hand threads. As the
cyclist pedaled, the action tended to tighten one pedal and loosen the
other, with the result that one pedal kept dropping off the bike.
Wilbur and Orville used right-hand threads on one pedal post and left-
hand threads on the other so the pedaling action tended to tighten
both pedals."

http://www.wright-brothers.org/Infor...t_Bicycles.htm

That's why tandem cranks are reversed on both sides. If you pedal a
normal crank backward (that's a tandem crank), both pedals would tend
to unscrew.

If you want to see a horde of posters slowly working through the
details of the light bearing friction (which isn't the problem) versus
the heavy precession effect (which is the problem), see this thread:

http://www.bikeforums.net/archive/in.../t-381225.html

When bicycles first appeared, left-hand pedals kept falling off .

The Wright brothers reversed the thread ion the left-hand pedal n 1900
and fixed the problem.

Since tandem cranks are reversed, they have both pedal threads
reversed.

The bearing friction would seem to work in the opposite direction, but
it's so light that it doesn't matter--it's the enormous effect of
precession that tends to unscrew a normally threaded left pedal.

Sheldon explained this:

Pedal Threading

Direction
The right pedal has a normal thread, but the left pedal has a left
(reverse) thread.

The reason for this is not obvious: The force from bearing
friction would, in fact, tend to unscrew pedals threaded in this
manner. It is not the bearing friction that makes pedals unscrew
themselves, but a phenomenon called "precession".

You can demonstrate this to yourself by performing a simple
experiment. Hold a pencil loosely in one fist, and move the end of it
in a circle. You will see that the pencil, as it rubs against the
inside of your fist, rotates in the opposite direction.

Ignorant people outside the bicycle industry sometimes make the
astonishing discovery that the way it has been done for 100 years is
"wrong." "Look at these fools, they go to the trouble of using a left
thread on one pedal, then the bozos go and put the left thread on the
wrong side! Shows that bicycle designers have no idea what they are
doing..."

Another popular theory of armchair engineers is that the threads
are done this way so that, if the pedal bearing locks up, the pedal
will unscrew itself instead of breaking the rider's ankle.

The left-threaded left pedal was not the result of armchair
theorizing, it was a solution to a real problem: people's left pedals
kept unscrewing! I have read that this was invented by the Wright
brothers, but I am not sure of this.

Note! The precession effect doesn't substitute for screwing your
pedals in good and tight. It is very important to do so. The threads
(like almost all threads on a bicycle) should be lubricated with
grease, or at least with oil.

http://www.sheldonbrown.com/gloss_p.html

Cheers,

Carl Fogel

Ultimate low-spoke-count rear wheel

wrote:
On Oct 2, 3:13 pm, thirty-six wrote:
On Oct 2, 7:00 pm, wrote:

On Sun, 02 Oct 2011 11:31:18 -0400, Frank Krygowski

wrote:
wrote:
http://www.gizmag.com/spokeless-bicycle/14216/

Intricate gearing:
http://www.gizmag.com/spokeless-bicy...icture/110818/
http://www.gizmag.com/spokeless-bicy...icture/110819/
http://www.gizmag.com/spokeless-bicy...icture/110820/
Cheers,

Carl Fogel

Those pedals better be held in with Loctite. Because they probably
didn't spend the money on a tandem front crank.

Dear Frank,

The "Shimano" on the crank is upside-down, so they must have used an
ordinary crank that was handy:
http://www.gizmag.com/spokeless-bicy...icture/110820/

There is indeed a reason why pedals come with left-hand and
right-hand threads, but this oddball probably won't be pedalled far
enough to reveal the problem.

Cheers,

Carl Fogel

It's for speed of assembly. With the bike held in the air by the seat
pin, the pedals are threaded on together by turning the cranks
backward. It's a simple single operation used to cut production
time. A pedal spanner is applied with the wheels on the ground and
cracked tight, leaving the cycle safe to operate. The direction of
thread is unimportant, a pedal may still come off if it is not
cracked tight. I have seen this happen with steel axles in steel
cranks.

Assembly speed? Maybe so, or at least that might be one consideration.
At what point does the chain get put on?

I've seen a Campy steel axle pedal come out of a Campy alu crank arm
in use-- a new pedal and crank, maybe 20 miles max into the first
ride, and the pedal was not, according to the post-accident
investigation, tightened "tight". It was a right-side pedal btw.

When I used to rent track bikes at Alkek Velodrome, one "overseer"
took me to task for using the leverage available in the pedal wrench.
Um, corrected later in the infield while supervision was supervising
elsewhere, thank you very much. I always just figured the pedal
spanner had an unusually long handle on it, compared to the other
"hand tools" for good reason. Only one of which "good reasons" was
getting tight pedals off g. After Reading Jobst, I would think that,
while a very tight pedal spindle might still fret a crank (arm) (g)
around the pedal eye, it should fret less than a looser one.
--D-y
thirty-six,
When do you think the pedals are installed? New bikes are shipped from the
factory with the pedals not installed, to reduce the size of the packaging.
I've never seen a bike shop mechanic install pedals in the way you
describe - all the ones I've seen install one pedal at a time. My years in
the shop happened a long time ago, though. Any current shop mechanics want
to weigh in?
Thanks,
Kerry