Funky crankset

Kerry Montgomery said:

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

Quoted message said:

Kerry Montgomery said:

Carl,
The rope just causes the treadle that's being pressed down to pull the
other
treadle back up, no? Was wondering if the front sprockets having teeth
all
the way around meant that the ratchet mechanism is between the treadle
crank
arm and the sprocket? If the ratchet mechanism was at the rear wheel, the
front sprockets could be sectors, not full circles.
Thanks for the great photo,
Kerry

Dear Kerry,

It's a treadle mechanism, but the details are a mystery to me.

I _think_ that the pedal arms are pushed down through about 90 degrees
and that they engage the inner track of tiny teeth on the huge
chain-rings with an arm whose end lets it ratchet back up at the end
of the down-stroke.

If so, the pair of huge full-circle chain-rings may advance endlessly,
but I can't really see how the hellish invention worked, what the
purpose of the mammoth chain rings was, or why on earth it was
created:

http://i9.tinypic.com/4taqys4.jpg

Weird old bicycle transmissions often stump me.

Here's a once-popular version that gave one forward gear ratio if you
pedalled forward and a different forward gear ratio if you pedalled
backward:

http://en.wikipedia.org/wiki/Retro-Direct

The page has links to other pages that usually increase my confusion,
but the basic idea is that you pedal forward to go fast on the flats
and pedal backward to climb hills.

Cheers,

Carl Fogel

Carl,
Looked more closely at the photos - I believe that you are right, the pedal
arms are the long end of an L-shaped piece that rotates about the "BB" axis.
The short end of that L-shaped piece points roughly toward the ground in the
photo, and clearly has a ratchet mechanism at its end that looks to engage
the tiny internal teeth. So, the chain-rings would advance endlessly, and
wouldn't need ratchets at the rear wheel. If that is the design, when
coasting, both the chain-rings would be spinning, and making quite the
ratchet sound, I'd think. Don't know why the high ratio, though.
Kerry

Dear Kerry,

The treadle arm has some gearing that engages the tiny teeth on the
inside of the huge chain rings.

There may be even more gearing concealed.

That unseen gearing may connect the pedal to the tiny teeth on the
inside of the chain ring at a ratio that reduces the monster chain
ring to a fairly normal ratio.

I like the coiled-wire protector that keeps the treadle-rope from
fraying on the chain and sprockets.

Someone could stop by the Metz museum in Freehold, New Jersey, take a
peek at the beast, and reveal its secrets:

http://www.metzbicyclemuseum.com

Cheers,

Carl Fogel

Quoted message said:

Quoted message said:

Quoted message said:

<[email hidden]> wrote
> This crazy thing is pure quackery. No marketing involved! Reminds me
> of the guy I knew who said he wanted a fixed gear bike with chainrings
> and cogs on both sides so he could get power with each stroke. Maybe
> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

Carl Sundquist said:

I recall seeing a Pinarello brochure showing atrackbike with a
drivetrain on both sides* Mind you, the hub would not be a flipflop, but
RH threads on the right side and LH threads on the left side of the hub.
The left side cog would need to be threaded LH as well. The left side
lockring (for those who would choose to use it) would need to have RH
threading.
*This has been done in the past as a two speed setup for kilo riders. A
larger cog is used to facilitate quicker acceleration, the cog on the
other side is used as a top end gear.

Quoted message said:

A Muzi said:

How does that work ? One side can be disengaged?
I remember the '75 Masi catalog with a photo-reverse track bike, but I've
never seen a reverse thread track cog. In the 20" world there are
reverse freewheels and matching left-drive hubs, but not track
AFAIK.

Quoted message said:

Here's a twin rear-cog and twin-front-sprocket monster:
http://i9.tinypic.com/4taqys4.jpg
I really like the rope that does something-or-other to the treadles
and fine gear teeth on the front.
It's from Gilbert King's "The Bicycle" photos of the Metz bicycle
museum.

That is not a fixie, it's just an Alenax with some extra emebellishments

Mr Sundquist says twin chain with two driving ratios. That sounds
horribly complex to me. I still don't 'get' it. Considering ASC
gearboxes actually work, why make a twin chain design? How is the gear
change effected?
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

On Mon, 21 May 2007 22:26:12 -0500, A Muzi <[email hidden]>

Quoted message said:

Quoted message said:

Quoted message said:

> <[email hidden]> wrote
>> This crazy thing is pure quackery. No marketing involved! Reminds me
>> of the guy I knew who said he wanted a fixed gear bike with chainrings
>> and cogs on both sides so he could get power with each stroke. Maybe
>> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

Carl Sundquist wrote:
> I recall seeing a Pinarello brochure showing atrackbike with a
> drivetrain on both sides* Mind you, the hub would not be a flipflop, but
> RH threads on the right side and LH threads on the left side of the hub.
> The left side cog would need to be threaded LH as well. The left side
> lockring (for those who would choose to use it) would need to have RH
> threading.
> *This has been done in the past as a two speed setup for kilo riders. A
> larger cog is used to facilitate quicker acceleration, the cog on the
> other side is used as a top end gear.

Quoted message said:

A Muzi said:

How does that work ? One side can be disengaged?
I remember the '75 Masi catalog with a photo-reverse track bike, but I've
never seen a reverse thread track cog. In the 20" world there are
reverse freewheels and matching left-drive hubs, but not track
AFAIK.

Quoted message said:

Here's a twin rear-cog and twin-front-sprocket monster:
http://i9.tinypic.com/4taqys4.jpg
I really like the rope that does something-or-other to the treadles
and fine gear teeth on the front.
It's from Gilbert King's "The Bicycle" photos of the Metz bicycle
museum.

That is not a fixie, it's just an Alenax with some extra emebellishments

Mr Sundquist says twin chain with two driving ratios. That sounds
horribly complex to me. I still don't 'get' it. Considering ASC
gearboxes actually work, why make a twin chain design? How is the gear
change effected?

Dear Andrew,

It's just an ultra-bizarre single speed, with no gear change.

http://i9.tinypic.com/4taqys4.jpg

A treadle action pushes down alternately on each huge chain ring,
somehow applying the force through tiny gear teeth just visible on the
_inside_ of the monster chain rings.

The rope, protected by the coiled wire from the chain, disengages and
raises one pedal and then the other.

Meanwhile, the chain rings advance endlessly.

If you look closely, you can see that one arm is not really a chain
ring arm--it's attached to the pedal at about 90 degrees and its end
somehow engages those tiny teeth on the inside of the chain ring.

The gearing involving the pedal and that weird arm is somehow so low
that it reduces the monstrous high gearing of those enormous chain
rings to normal gearing. (Don't ask me how.)

In 1898, strange designs were popular, but this one does seem to
border on lunacy, which naturally appealed to me.

Cheers,

Carl Fogel

Quoted message said:

Quoted message said:

Quoted message said:

>> <[email hidden]> wrote
>>> This crazy thing is pure quackery. No marketing involved! Reminds me
>>> of the guy I knew who said he wanted a fixed gear bike with chainrings
>>> and cogs on both sides so he could get power with each stroke. Maybe
>>> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

Quoted message said:

> Carl Sundquist wrote:
>> I recall seeing a Pinarello brochure showing atrackbike with a
>> drivetrain on both sides* Mind you, the hub would not be a flipflop, but
>> RH threads on the right side and LH threads on the left side of the hub.
>> The left side cog would need to be threaded LH as well. The left side
>> lockring (for those who would choose to use it) would need to have RH
>> threading.
>> *This has been done in the past as a two speed setup for kilo riders. A
>> larger cog is used to facilitate quicker acceleration, the cog on the
>> other side is used as a top end gear.

Quoted message said:

Quoted message said:

Quoted message said:

A Muzi <[email hidden]> wrote:
> How does that work ? One side can be disengaged?
> I remember the '75 Masi catalog with a photo-reverse track bike, but I've
> never seen a reverse thread track cog. In the 20" world there are
> reverse freewheels and matching left-drive hubs, but not track
> AFAIK.

Quoted message said:

Quoted message said:

Quoted message said:

Here's a twin rear-cog and twin-front-sprocket monster:
http://i9.tinypic.com/4taqys4.jpg
I really like the rope that does something-or-other to the treadles
and fine gear teeth on the front.
It's from Gilbert King's "The Bicycle" photos of the Metz bicycle
museum.

Quoted message said:

A Muzi said:

That is not a fixie, it's just an Alenax with some extra emebellishments
Mr Sundquist says twin chain with two driving ratios. That sounds
horribly complex to me. I still don't 'get' it. Considering ASC
gearboxes actually work, why make a twin chain design? How is the gear
change effected?

Quoted message said:

It's just an ultra-bizarre single speed, with no gear change.
http://i9.tinypic.com/4taqys4.jpg
A treadle action pushes down alternately on each huge chain ring,
somehow applying the force through tiny gear teeth just visible on the
_inside_ of the monster chain rings.
The rope, protected by the coiled wire from the chain, disengages and
raises one pedal and then the other.
Meanwhile, the chain rings advance endlessly.
If you look closely, you can see that one arm is not really a chain
ring arm--it's attached to the pedal at about 90 degrees and its end
somehow engages those tiny teeth on the inside of the chain ring.
The gearing involving the pedal and that weird arm is somehow so low
that it reduces the monstrous high gearing of those enormous chain
rings to normal gearing. (Don't ask me how.)
In 1898, strange designs were popular, but this one does seem to
border on lunacy, which naturally appealed to me.

The bike _you_ referenced was just a pre-Alenax.
It's been done. To death. Whatever.

My question was to Mr Sundquist about a "twin chain track bike with gear
change". Can't see any reason to use twin chains for a 2-speed fixie and
moreover I still can't see how that could even work. Unlike an Alenax,
I find that intriguing.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

On Mon, 21 May 2007 23:10:20 -0500, A Muzi <[email hidden]>

Quoted message said:

Quoted message said:

Quoted message said:

>>> <[email hidden]> wrote
>>>> This crazy thing is pure quackery. No marketing involved! Reminds me
>>>> of the guy I knew who said he wanted a fixed gear bike with chainrings
>>>> and cogs on both sides so he could get power with each stroke. Maybe
>>>> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

>> Carl Sundquist wrote:
>>> I recall seeing a Pinarello brochure showing atrackbike with a
>>> drivetrain on both sides* Mind you, the hub would not be a flipflop, but
>>> RH threads on the right side and LH threads on the left side of the hub.
>>> The left side cog would need to be threaded LH as well. The left side
>>> lockring (for those who would choose to use it) would need to have RH
>>> threading.
>>> *This has been done in the past as a two speed setup for kilo riders. A
>>> larger cog is used to facilitate quicker acceleration, the cog on the
>>> other side is used as a top end gear.

Quoted message said:

Quoted message said:

> A Muzi <[email hidden]> wrote:
>> How does that work ? One side can be disengaged?
>> I remember the '75 Masi catalog with a photo-reverse track bike, but I've
>> never seen a reverse thread track cog. In the 20" world there are
>> reverse freewheels and matching left-drive hubs, but not track
>> AFAIK.

Quoted message said:

Quoted message said:

[email hidden] wrote:
> Here's a twin rear-cog and twin-front-sprocket monster:
> http://i9.tinypic.com/4taqys4.jpg
> I really like the rope that does something-or-other to the treadles
> and fine gear teeth on the front.
> It's from Gilbert King's "The Bicycle" photos of the Metz bicycle
> museum.

Quoted message said:

A Muzi said:

That is not a fixie, it's just an Alenax with some extra emebellishments
Mr Sundquist says twin chain with two driving ratios. That sounds
horribly complex to me. I still don't 'get' it. Considering ASC
gearboxes actually work, why make a twin chain design? How is the gear
change effected?

Quoted message said:

It's just an ultra-bizarre single speed, with no gear change.
http://i9.tinypic.com/4taqys4.jpg
A treadle action pushes down alternately on each huge chain ring,
somehow applying the force through tiny gear teeth just visible on the
_inside_ of the monster chain rings.
The rope, protected by the coiled wire from the chain, disengages and
raises one pedal and then the other.
Meanwhile, the chain rings advance endlessly.
If you look closely, you can see that one arm is not really a chain
ring arm--it's attached to the pedal at about 90 degrees and its end
somehow engages those tiny teeth on the inside of the chain ring.
The gearing involving the pedal and that weird arm is somehow so low
that it reduces the monstrous high gearing of those enormous chain
rings to normal gearing. (Don't ask me how.)
In 1898, strange designs were popular, but this one does seem to
border on lunacy, which naturally appealed to me.

The bike _you_ referenced was just a pre-Alenax.
It's been done. To death. Whatever.

My question was to Mr Sundquist about a "twin chain track bike with gear
change". Can't see any reason to use twin chains for a 2-speed fixie and
moreover I still can't see how that could even work. Unlike an Alenax,
I find that intriguing.

Dear Andrew,

Ah, I misunderstood you--sorry.

Cheers,

Carl Fogel

Quoted message said:

On 21 May 2007 00:25:32 -0700, "[email hidden]"

Quoted message said:

Quoted message said:

On Sun, 20 May 2007 23:31:03 GMT, "Leo Lichtman"

Quoted message said:

Quoted message said:

<[email hidden]> wrote:

Quoted message said:

Quoted message said:

><[email hidden]> wrote: Actually, when I think about it some, you
>can't have the pedal welded to the shaft at anything but a tangent to the
>circle, like the seat of a ferris wheel. The more the flat of the pedal
>deviates from a tangent, the more it's going to dump the rider's foot as
>soon as the rider pushes down.
>^^^^^^^^^^^^^^^^^
>Carl, picture a ring gear, teeth pointed radially inward. Now picture a
>small pinion meshed with the ring gear. Now attach a pedal rigidly to the
>pinion, at some arbitrary angle. You can now roll the pinion around the
>inside of the ring gear until the pedal is horizontal. If you now mount
>this assembly on the end of a crank, you can put your foot on the pedal.
>THIS IS IMPORTANT: The ring gear has to be free to rotate with respect to
>the crank. If you now start to pedal, the spindle pinion will drive the
>ring gear, extending or shortening the effective crank length.

Quoted message said:

Quoted message said:

Dear Leo,

Quoted message said:

Quoted message said:

I suppose that you could use gearing in the end of the crank in some
way, but you don't need any gearing.

Quoted message said:

Quoted message said:

All you need are ball bearings in the black ring, like earlier pedal
designs.

Quoted message said:

Quoted message said:

Here's a crude diagram:

Quoted message said:

Quoted message said:

http://i17.tinypic.com/66y4s53.jpg

Quoted message said:

Quoted message said:

You can get away with welding the pedals to the pedal shaft if you
weld them at a tangent to the black free-spinning rings.

Quoted message said:

Then it is just a overly complex Ramesy pedal.

Quoted message said:

Quoted message said:

But the auction pictures show the pedals at up to 90 degrees to the
tangent of the black rings, so the pedals are presumably just ordinary
free-spinning pedals.

Quoted message said:

Quoted message said:

If you welded the pedals off-tangent, they'd dump the rider's foot as
he pushed down, just as an off-tangent ferris-wheel seat would dump
passengers.

Quoted message said:

No doubt cleats, straps, and tightly laced stiff-soled shoes are a
good idea, but I don' think non-tangent welded pedals would throw
one's feet. No worse than when you pedal with only the tips of you
toes barely over the spindle of normal pedals. Since you feet are not
free-standing weights that are just plonked onto the pedals like
ferris-wheel victims, you have your ankles and calf muscles to counter
the tippieness of the non-tangent pedals. Maybe the point of this
thing isn't so much to create an elliptical pedal path or to have a
crank position dependent crank length, but rather to get the calf
muscles in on the action?

Quoted message said:

Quoted message said:

Maybe some gearing would get around all this, but free-spinning ball
bearings are simpler. Possibly gearing would force some strange
changes in where the effective crank length changed around the pedal
cycle, but I suspect that it's all pretty much pointless.

Quoted message said:

I agree, gearing is too complex for even such silly thing as this.

Quoted message said:

Joseph

Dear Joseph & Leo,

I asked the seller:

"Hi, Can you tell me if the pedals rotate freely on the pedal shaft
and if the black ring from which the pedal shaft sticks out rotates
freely in the end of the crank? Or is there some hidden internal
gearing? Thanks, Carl Fogel"

He replied:

"The pedal is stuck onto the black ring and doesn't rotate freely.
Regards David"

I _think_ that this means that I was wrong and that the pedal, shaft,
and ring all act as a solid piece--the flat pedal stays at that angle,
across the black ring instead of at a tangent or spinning.

The reply says nothing about whether the black ring rotates or any
internal gearing, so I'm baffled.

If the ring rotates freely (no comment from seller on this point),
then pushing down on the pedal fixed across the black ring should tilt
the pedal horribly downward. But maybe the huge heel plate overcomes
the comparatively small leverage of the pedal spindle on the edge of
the circle?

I couldn't find anything about Colrout on the internet.

Cheers,

Carl Fogel

It seems I deduced correctly. You say the heel plates may help counter
the "dumping" action, but I think if there is any dumping action it
happens the other way!

Joseph

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

Quoted message said:

Quoted message said:

Quoted message said:

>>> <[email hidden]> wrote
>>>> This crazy thing is pure quackery. No marketing involved! Reminds me
>>>> of the guy I knew who said he wanted a fixed gear bike with
>>>> chainrings
>>>> and cogs on both sides so he could get power with each stroke. Maybe
>>>> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

>> Carl Sundquist wrote:
>>> I recall seeing a Pinarello brochure showing atrackbike with a
>>> drivetrain on both sides* Mind you, the hub would not be a flipflop,
>>> but
>>> RH threads on the right side and LH threads on the left side of the
>>> hub.
>>> The left side cog would need to be threaded LH as well. The left side
>>> lockring (for those who would choose to use it) would need to have RH
>>> threading.
>>> *This has been done in the past as a two speed setup for kilo riders.
>>> A
>>> larger cog is used to facilitate quicker acceleration, the cog on the
>>> other side is used as a top end gear.

Quoted message said:

Quoted message said:

> A Muzi <[email hidden]> wrote:
>> How does that work ? One side can be disengaged?
>> I remember the '75 Masi catalog with a photo-reverse track bike, but
>> I've
>> never seen a reverse thread track cog. In the 20" world there are
>> reverse freewheels and matching left-drive hubs, but not track
>> AFAIK.

Quoted message said:

Quoted message said:

[email hidden] wrote:
> Here's a twin rear-cog and twin-front-sprocket monster:
> http://i9.tinypic.com/4taqys4.jpg
> I really like the rope that does something-or-other to the treadles
> and fine gear teeth on the front.
> It's from Gilbert King's "The Bicycle" photos of the Metz bicycle
> museum.

Quoted message said:

A Muzi said:

That is not a fixie, it's just an Alenax with some extra emebellishments
Mr Sundquist says twin chain with two driving ratios. That sounds
horribly complex to me. I still don't 'get' it. Considering ASC
gearboxes actually work, why make a twin chain design? How is the gear
change effected?

Quoted message said:

It's just an ultra-bizarre single speed, with no gear change.
http://i9.tinypic.com/4taqys4.jpg
A treadle action pushes down alternately on each huge chain ring,
somehow applying the force through tiny gear teeth just visible on the
_inside_ of the monster chain rings.
The rope, protected by the coiled wire from the chain, disengages and
raises one pedal and then the other.
Meanwhile, the chain rings advance endlessly.
If you look closely, you can see that one arm is not really a chain
ring arm--it's attached to the pedal at about 90 degrees and its end
somehow engages those tiny teeth on the inside of the chain ring. The
gearing involving the pedal and that weird arm is somehow so low
that it reduces the monstrous high gearing of those enormous chain
rings to normal gearing. (Don't ask me how.)
In 1898, strange designs were popular, but this one does seem to
border on lunacy, which naturally appealed to me.

The bike _you_ referenced was just a pre-Alenax.
It's been done. To death. Whatever.

My question was to Mr Sundquist about a "twin chain track bike with gear
change". Can't see any reason to use twin chains for a 2-speed fixie and
moreover I still can't see how that could even work. Unlike an Alenax, I
find that intriguing.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

Andrew,
From some Google searching:
http://www.bikeforums.net/archive/index.php/t-159462.html (about half-way
down the page there is a description)
http://archives.cbc.ca/IDCC-1-41-1341-8024/sports/olympics_podium/ (at 1:44
in the video you can see the double-sided drive)
Couldn't find a copy for sale anywhere of:
Champion on Wheels: A Biography of Jocelyn Lovell
by Mary Frances Coady
paper, $4.95, ISBN 0-7725-1568-9

Kerry

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

Quoted message said:

Mr Sundquist says twin chain with two driving ratios. That sounds horribly
complex to me. I still don't 'get' it. Considering ASC gearboxes actually
work, why make a twin chain design? How is the gear change effected?

It is complex, in that you need to have the "high" gear precisely unwound a
specific number of revolutions and set the rear wheel and crank placement
exactly where you want them for the start in order for the "high" gear to
engage when you want it to. I didn't see Lovell's bike, but the
cyclingforums link describes it fairly well. Gene Samuels of Trinidad used a
two gear system, but used a conventional road crank with both chainrings on
the same side of the bike. He had fabricated a special cog that was offset
for the final drive, along with a single freewheel.

I think they got around the fixed cog rule by a slight loophole: for time
trial events on the track where there is only one bike on the track at a
time, you were not required to ride a fixed gear. Either that rule has been
amended or become moot, since many kilos are now ridden pursuit style with
two riders on the track at the same time.

On Mon, 21 May 2007 23:10:20 -0500, A Muzi <[email hidden]>

Quoted message said:

Quoted message said:

Quoted message said:

>>> <[email hidden]> wrote
>>>> This crazy thing is pure quackery. No marketing involved! Reminds me
>>>> of the guy I knew who said he wanted a fixed gear bike with chainrings
>>>> and cogs on both sides so he could get power with each stroke. Maybe
>>>> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

>> Carl Sundquist wrote:
>>> I recall seeing a Pinarello brochure showing atrackbike with a
>>> drivetrain on both sides* Mind you, the hub would not be a flipflop, but
>>> RH threads on the right side and LH threads on the left side of the hub.
>>> The left side cog would need to be threaded LH as well. The left side
>>> lockring (for those who would choose to use it) would need to have RH
>>> threading.
>>> *This has been done in the past as a two speed setup for kilo riders. A
>>> larger cog is used to facilitate quicker acceleration, the cog on the
>>> other side is used as a top end gear.

Quoted message said:

Quoted message said:

> A Muzi <[email hidden]> wrote:
>> How does that work ? One side can be disengaged?
>> I remember the '75 Masi catalog with a photo-reverse track bike, but I've
>> never seen a reverse thread track cog. In the 20" world there are
>> reverse freewheels and matching left-drive hubs, but not track
>> AFAIK.

Quoted message said:

Quoted message said:

[email hidden] wrote:
> Here's a twin rear-cog and twin-front-sprocket monster:
> http://i9.tinypic.com/4taqys4.jpg
> I really like the rope that does something-or-other to the treadles
> and fine gear teeth on the front.
> It's from Gilbert King's "The Bicycle" photos of the Metz bicycle
> museum.

Quoted message said:

A Muzi said:

That is not a fixie, it's just an Alenax with some extra emebellishments
Mr Sundquist says twin chain with two driving ratios. That sounds
horribly complex to me. I still don't 'get' it. Considering ASC
gearboxes actually work, why make a twin chain design? How is the gear
change effected?

Quoted message said:

It's just an ultra-bizarre single speed, with no gear change.
http://i9.tinypic.com/4taqys4.jpg
A treadle action pushes down alternately on each huge chain ring,
somehow applying the force through tiny gear teeth just visible on the
_inside_ of the monster chain rings.
The rope, protected by the coiled wire from the chain, disengages and
raises one pedal and then the other.
Meanwhile, the chain rings advance endlessly.
If you look closely, you can see that one arm is not really a chain
ring arm--it's attached to the pedal at about 90 degrees and its end
somehow engages those tiny teeth on the inside of the chain ring.
The gearing involving the pedal and that weird arm is somehow so low
that it reduces the monstrous high gearing of those enormous chain
rings to normal gearing. (Don't ask me how.)
In 1898, strange designs were popular, but this one does seem to
border on lunacy, which naturally appealed to me.

The bike _you_ referenced was just a pre-Alenax.
It's been done. To death. Whatever.

My question was to Mr Sundquist about a "twin chain track bike with gear
change". Can't see any reason to use twin chains for a 2-speed fixie and
moreover I still can't see how that could even work. Unlike an Alenax,
I find that intriguing.

Dear Andrew,

Dianne has explained two such bikes:

http://groups.google.com/group/rec.bicycles.tech/msg/9e13d82a8b094834

Cheers,

Carl Fogel

Quoted message said:

Quoted message said:

Quoted message said:

>>>> <[email hidden]> wrote
>>>>> This crazy thing is pure quackery. No marketing involved! Reminds me
>>>>> of the guy I knew who said he wanted a fixed gear bike with chainrings
>>>>> and cogs on both sides so he could get power with each stroke. Maybe
>>>>> he worked at Gipiemme in a former life! I still want it though.

Quoted message said:

Quoted message said:

Quoted message said:

>>> Carl Sundquist wrote:
>>>> I recall seeing a Pinarello brochure showing atrackbike with a
>>>> drivetrain on both sides* Mind you, the hub would not be a flipflop, but
>>>> RH threads on the right side and LH threads on the left side of the hub.
>>>> The left side cog would need to be threaded LH as well. The left side
>>>> lockring (for those who would choose to use it) would need to have RH
>>>> threading.
>>>> *This has been done in the past as a two speed setup for kilo riders. A
>>>> larger cog is used to facilitate quicker acceleration, the cog on the
>>>> other side is used as a top end gear.

-snip-

Quoted message said:

Dianne has explained two such bikes:
http://groups.google.com/group/rec.bicycles.tech/msg/9e13d82a8b094834

OK, that is clever.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

On May 20, 3:31 pm, "Leo Lichtman" <[email hidden]>

Quoted message said:

<[email hidden]> wrote: Actually, when I think about it some, you

can't have the pedal welded to the shaft at anything but a tangent to the
circle, like the seat of a ferris wheel. The more the flat of the pedal
deviates from a tangent, the more it's going to dump the rider's foot as
soon as the rider pushes down.
^^^^^^^^^^^^^^^^^
Carl, picture a ring gear, teeth pointed radially inward. Now picture a
small pinion meshed with the ring gear. Now attach a pedal rigidly to the
pinion, at some arbitrary angle. You can now roll the pinion around the
inside of the ring gear until the pedal is horizontal. If you now mount
this assembly on the end of a crank, you can put your foot on the pedal.
THIS IS IMPORTANT: The ring gear has to be free to rotate with respect to
the crank. If you now start to pedal, the spindle pinion will drive the
ring gear, extending or shortening the effective crank length.

Leo- while I understand your idea, I really, really doubt that this
is the case with this cranky crank. There doesn't appear to be room
for a series of gears transmitting power down the length of the crank,
nor are there any external indications that such is contained in the
crank, nor is there an evidence of a seperate gear at the spindle
attachment. I'd expect all of these to be apparent in the photos. The
crank appears to be solid, forged aluminum.

I think (as others have suggested) that it's a version of the Ramsey/
Dura-Ace AX/stirrup pedal, where the pedal pivot is well above the
bottom of the foot. Whether it's an advantage, well, I dunno.

Yo, 'zark: not only can I not forget the Houdaille PowerCam, I *had*
one. Never mounted it on a bike, though- the right bearing cup ( which
also mounted the cam) was way too cheesy, even for my eccentric
tastes.

Jeff