Lowest Possible Gears

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

Quoted message said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts?

Cheapest option is to change the chainset for one with a 20t inner ring.
Should be quite easy to find. You may need to change the front mech, but I
would just try it first. Of course you will lose high gears...

cheers,
clive

cmcanulty said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts? I am also interested in doing the same
with a folding bike but be able to stay under $600 or so. Thanks,
Carol M

This doesn't directly answer your question, but I've seen loads of
people on bikes who drag their dogs along behind them by leash....I've
never had a chance to ask the dogs whether they needed a lower gear....

You can always fit a Schlumpf Mountain Drive but it costs about 250 UK
pounds. This will give you gears down to around 13" using the supplied 48
tooth chainwheel. If you reduce this to say 40 teeth your lowest will be
11" up to 84" top. Even lower is possible!!

http://www.schlumpf.ch/md_engl.htm

If you use the gear calculator on Kinetics' web site it does all the
Schlumpf calculations for you.

http://www.kinetics.org.uk/html/mountain_drive.shtml

cmcanulty said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts? I am also interested in doing the same
with a folding bike but be able to stay under $600 or so. Thanks,
Carol M

All mountain bike triple cranks come with 22 tooth inner chainrings.
If you find one using a 5 bolt 58mm or 56mm bolt circle diameter, you
can put on a 20 tooth inner ring. Here is a website describing that.
I'm not suggesting this crank specifically, just the info about
getting smaller inner rings.

http://www.peterwhitecycles.com/carmina.asp

Easiest way to get a lower gear is to use smaller tires. If you are
using big fat 26" knobby mountain bike tires, change them to skinny
small 26" slicks of 1.125" or 1.25". You go from roughly a 26"
diameter with knobby tires to abotu a 24.5" diameter. And get lower
gears all across the range. 24x34 with 26" diameter wheel equals 18.3
gear inches. 24x34 with 24.5" diameter wheel equals 17.3 gear
inches. 5.5% reduction. And rolling resistance is much less with
slicks than knobbies.

On 10 Apr 2007 06:46:09 -0700, "cmcanulty" <[email hidden]>

Quoted message said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts? I am also interested in doing the same
with a folding bike but be able to stay under $600 or so. Thanks,
Carol M

Dear Carol,

You may be able to get a smaller 20-tooth front sprocket and a larger
38-tooth rear sprocket. Browse this thread:

http://groups.google.com/group/rec.bicycles.tech/msg/941796a0dc053a23

But lower gearing may not work very well. You're already near the
lower limit of practical gearing for a normal rider on two wheels.

That is, it will soon be easier and faster to get off and walk,
pushing the bicycle, than to spin the pedals wildly while trying to
balance.

(A heavily loaded bicycle is much easier to push than a wheelbarrow.)

The problem can be seen if you calculate the overall ratio of how far
your foot moves around the pedal circle, compared to how far the rear
wheel rolls.

Bicycles work by increasing our "stride" enormously. At high speed in
a high gear on flat ground, your rear tire may roll forward eight
times as far as your foot moves in the circle on the pedal. In other
words, moving your foot only 3 feet around a circle pushes you 24 feet
forward.

The table below shows what happens to this huge "stride" if we use
extremely low gearing to toil up hills with a heavy load on a bike
with a 172.5 mm crank length and 2045 mm circumference mtb tires.

Remember, the "overall ratio" is how far your foot moves in a circle
on the pedal compared to how far your rear tire rolls forward on the
ground. (The length of the pedal arm and the diameter of the tire
change the simple front-to-rear sprocket gear ratio.)

At an "overall ratio" of 1.0, your feet on the pedals travel just as
far in circles as they would if you were walking, and you're losing
power to chain and tire inefficiencies while trying to balance at low
speed.

front rear overall rpm @
teeth teeth ratio 4 mph
----- ----- ------- -----
24 34 1.33 74
24 38 1.19 83
20 34 1.11 89
20 38 0.99 100

For comparison, most people will walk at 60~90 steps per minute and
around 3-4 mph.

At the low speeds forced by ultra-low gearing, you'll tend to stall
and have to put a foot down for balance when you try to shift gears or
merely hit a bump and lose 1 mph.

Some riders with severe leg problems get around the stalling problem
by switching to tricycles for stability.

Cheers,

Carl Fogel

email hidden said:

cmcanulty said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts? I am also interested in doing the same
with a folding bike but be able to stay under $600 or so. Thanks,
Carol M

Easiest way to get a lower gear is to use smaller tires.

The logical extension of this, if your frame geometry and brake mounts
can take it, is to switch to 24" wheels. There are plenty of tyre
choices in that size

OD of a 50-507 Schwalbe Big Apple should be just under 24", giving a
gear of 15.5" on the almost universal 22/34 gearing, and a smidge over
14" if your chainset will take a 20t granny ring

Kinky Cowboy*

*Batteries not included
May contain traces of nuts
Your milage may vary

On Tue, 10 Apr 2007 20:40:35 +0100, Kinky Cowboy <[email hidden]>

Quoted message said:

email hidden said:

cmcanulty said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts? I am also interested in doing the same
with a folding bike but be able to stay under $600 or so. Thanks,
Carol M

Easiest way to get a lower gear is to use smaller tires.

The logical extension of this, if your frame geometry and brake mounts
can take it, is to switch to 24" wheels. There are plenty of tyre
choices in that size

OD of a 50-507 Schwalbe Big Apple should be just under 24", giving a
gear of 15.5" on the almost universal 22/34 gearing, and a smidge over
14" if your chainset will take a 20t granny ring

Kinky Cowboy*

Dear Kinky,

The smaller tire and front ring will lower the gearing, but they may
well be impractical.

Using the 1916 mm circumference suggested for 24" tires by
cyclocomputer tables and a 172.5 mm crank produces these results:

front back overall rpm @
gear gear ratio 4 mph
----- ----- ------- -----
22 34 1.215 81
20 34 1.040 95

"Overall ratio" is how far the rear wheel rolls forward compared to
how far the rider's foot moves around the pedal circle.

At 20x34 with that wheel and crank, you roll forward 104 feet while
your foot moves 100 feet in a circle.

It would probably be less work to get off and push the bike, avoiding
the transmission loss and the fuss of balancing while presumably
struggling uphill at 95 rpm at walking speed.

Pushing would also eliminate the problem of stalling and toppling when
the front tire hits a bump on the road.

Cheers,

Carl Fogel

Quoted message said:

On 10 Apr 2007 06:46:09 -0700, "cmcanulty" <[email hidden]>

Quoted message said:

I carry a dog and all my shopping , library books, etc on my bike and
am always looking for the lowest possible gear setup with standard
available setups. I currently have a 26" wheel mt bike with a 18" gear
(24 tooth on front, 34 tooth on back). Anyone have a way to go lower
with easily available parts? I am also interested in doing the same
with a folding bike but be able to stay under $600 or so. Thanks,
Carol M

Dear Carol,

You may be able to get a smaller 20-tooth front sprocket and a larger
38-tooth rear sprocket. Browse this thread:

http://groups.google.com/group/rec.bicycles.tech/msg/941796a0dc053a23

But lower gearing may not work very well. You're already near the
lower limit of practical gearing for a normal rider on two wheels.

That is, it will soon be easier and faster to get off and walk,
pushing the bicycle, than to spin the pedals wildly while trying to
balance.

(A heavily loaded bicycle is much easier to push than a wheelbarrow.)

The problem can be seen if you calculate the overall ratio of how far
your foot moves around the pedal circle, compared to how far the rear
wheel rolls.

Bicycles work by increasing our "stride" enormously. At high speed in
a high gear on flat ground, your rear tire may roll forward eight
times as far as your foot moves in the circle on the pedal. In other
words, moving your foot only 3 feet around a circle pushes you 24 feet
forward.

The table below shows what happens to this huge "stride" if we use
extremely low gearing to toil up hills with a heavy load on a bike
with a 172.5 mm crank length and 2045 mm circumference mtb tires.

Remember, the "overall ratio" is how far your foot moves in a circle
on the pedal compared to how far your rear tire rolls forward on the
ground. (The length of the pedal arm and the diameter of the tire
change the simple front-to-rear sprocket gear ratio.)

At an "overall ratio" of 1.0, your feet on the pedals travel just as
far in circles as they would if you were walking, and you're losing
power to chain and tire inefficiencies while trying to balance at low
speed.

front rear overall rpm @
teeth teeth ratio 4 mph
----- ----- ------- -----
24 34 1.33 74
24 38 1.19 83
20 34 1.11 89
20 38 0.99 100

For comparison, most people will walk at 60~90 steps per minute and
around 3-4 mph.

At the low speeds forced by ultra-low gearing, you'll tend to stall
and have to put a foot down for balance when you try to shift gears or
merely hit a bump and lose 1 mph.

Some riders with severe leg problems get around the stalling problem
by switching to tricycles for stability.

Cheers,

Carl Fogel

I forgot to mention Mountain Tamer devices. Read here for info and
whether it would work for you or not.

http://www.abundantadventures.com/quads.html

Carl, you can easily maintain your balance and still ride up hills at
less than 4 mph. You could even swerve side to side across the road
to decrease the angle and help stay upright if your speed gets much
lower. It is almost always easier to ride up hills than walk and push
the bike. Assuming you have a low enough gear to pedal without having
to put an extraordinary amount of force on the pedals. Try walking up
one of those Colorado mountains you live near at 3-4 mph while pushing
a loaded touring bike and then ride up the same stretch at 4 mph.
Biking up is easier. You may be correct that you actually use less
energy walking and pushing, but it won't feel like it.

"Mountaintamer" allows you to mount rear cogs in the front--you can get
obscenely low gears. I remember looking down once on a steep hill, and saw
my bottom foot moving backwards faster than the bike was moving forward.

On 10 Apr 2007 14:31:44 -0700, "[email hidden]"
<[email hidden]> wrote:

[snip]

Quoted message said:

Try walking up
one of those Colorado mountains you live near at 3-4 mph while pushing
a loaded touring bike and then ride up the same stretch at 4 mph.
Biking up is easier. You may be correct that you actually use less
energy walking and pushing, but it won't feel like it.

Dear Russell,

Sorry, but I'm not following the logic.

You seem to be saying that "biking up is easier" but it uses more
energy?

As for not feeling like it, walking is if anything more natural than
the circular raise-lower cycle of the pedal. Pedaling at such low
speeds turns a modest hiking slope into a steep stairway.

It might feel better in terms of accomplishment and our natural RBT
prejudice that feet are meant to pedal, not to walk, but if it uses
more energy, it will feel harder, not easier.

Note where such logic would eventually lead--a 10 x 34 would make
riding up a hill even "easier", despite requiring twice as many leg
lifts at half the speed. The lower limit for useful uphill bicycle
gearing for normal riders is somewhere down around walking speed.

This is why we just don't see much of the ultra-low gearing setups
that people occasionally wish for on RBT. Bicyclists will try almost
anything, but the extremes usually filter themselves out quickly.

When the North Vietnamese were trundling military supplies south
through mountain trails on heavily-laden bikes, they pushed instead of
trying to fit ultra-low gearing.

I'm open, however, to correction. Does anyone actually have a 20 x 38
on a 700c or MTB? If so, try riding up a trail steep enough to require
it for a few hundred yards one day, and then try pushing the bike up
the same trail again.

Years ago, I watched a pair of ultra-low geared MTB's spinning
furiously up a steep slope in the Wet Mountains and was surprised to
find that I was overtaking them on foot.

Beginning trials riders often re-discover this sort of thing. There's
a limit to how low you can usefully gear a motorcycle, given the
engine characteristics, and the stock trials machines are usually
close to it.

Same thing with the human engine--gear a bicycle too low for too steep
a climb, and you work harder than you would just walking. You'd have
to put a hobble on the hiker's boots to even things up. The Fargo
Street Hill climbers use surprisingly high gearing for their ~30%
grade.

Cheers,

Carl Fogel

<[email hidden]> wrote: (clip) Years ago, I watched a pair of
ultra-low geared MTB's spinning furiously up a steep slope in the Wet
Mountains and was surprised to find that I was overtaking them on foot.
^^^^^^^^^^^^^^^^^^^
That has happened to me, except that I was the one riding and being passed.
However, they passes me so slowly that we had plenty of time to have a
conversation about it. I figured they were just stronger than me.

Low gearing is useful for short, very steep stretches. If you can stay on
the bike and overcome a brief steep uphill, you avoid dismounting and then
trying to restart. I have been caught on some hills that were so steep
that a single pedal stroke did not give me enough momentum to get my other
foot on the pedal. Then I had to keep walking, or find a tree or fencepost
to hold on to. I'm talking about trails so narrow that turning the bike
sideways is not an option.

-snip-

Quoted message said:

Quoted message said:

Try walking up
one of those Colorado mountains you live near at 3-4 mph while pushing
a loaded touring bike and then ride up the same stretch at 4 mph.
Biking up is easier. You may be correct that you actually use less
energy walking and pushing, but it won't feel like it.

Quoted message said:

Sorry, but I'm not following the logic.
You seem to be saying that "biking up is easier" but it uses more
energy?
As for not feeling like it, walking is if anything more natural than
the circular raise-lower cycle of the pedal. Pedaling at such low
speeds turns a modest hiking slope into a steep stairway.
It might feel better in terms of accomplishment and our natural RBT
prejudice that feet are meant to pedal, not to walk, but if it uses
more energy, it will feel harder, not easier.
Note where such logic would eventually lead--a 10 x 34 would make
riding up a hill even "easier", despite requiring twice as many leg
lifts at half the speed. The lower limit for useful uphill bicycle
gearing for normal riders is somewhere down around walking speed.
This is why we just don't see much of the ultra-low gearing setups
that people occasionally wish for on RBT. Bicyclists will try almost
anything, but the extremes usually filter themselves out quickly.

When the North Vietnamese were trundling military supplies south
through mountain trails on heavily-laden bikes, they pushed instead of
trying to fit ultra-low gearing.

I'm open, however, to correction. Does anyone actually have a 20 x 38
on a 700c or MTB? If so, try riding up a trail steep enough to require
it for a few hundred yards one day, and then try pushing the bike up
the same trail again.

Years ago, I watched a pair of ultra-low geared MTB's spinning
furiously up a steep slope in the Wet Mountains and was surprised to
find that I was overtaking them on foot.

Beginning trials riders often re-discover this sort of thing. There's
a limit to how low you can usefully gear a motorcycle, given the
engine characteristics, and the stock trials machines are usually
close to it.

Same thing with the human engine--gear a bicycle too low for too steep
a climb, and you work harder than you would just walking. You'd have
to put a hobble on the hiker's boots to even things up. The Fargo
Street Hill climbers use surprisingly high gearing for their ~30%
grade.

heh heh great image! We used a photo of Vietcong pushing 400lbs of gear
on a Peugeot though the jungle in a Peugeot ad once. lotsa flak. [see
also 'Bicycles in War']

In my experience, most cyclists will prefer a possibly 'inefficient' low
gear to walking. It's a psychological barrier most people simply do not
like to cross. YMMV. I do not have an opinion on what's 'best', having
done both.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

On Tue, 10 Apr 2007 20:12:29 -0500, A Muzi <[email hidden]>

Quoted message said:

-snip-

Quoted message said:

Quoted message said:

Try walking up
one of those Colorado mountains you live near at 3-4 mph while pushing
a loaded touring bike and then ride up the same stretch at 4 mph.
Biking up is easier. You may be correct that you actually use less
energy walking and pushing, but it won't feel like it.

Quoted message said:

Sorry, but I'm not following the logic.
You seem to be saying that "biking up is easier" but it uses more
energy?
As for not feeling like it, walking is if anything more natural than
the circular raise-lower cycle of the pedal. Pedaling at such low
speeds turns a modest hiking slope into a steep stairway.
It might feel better in terms of accomplishment and our natural RBT
prejudice that feet are meant to pedal, not to walk, but if it uses
more energy, it will feel harder, not easier.
Note where such logic would eventually lead--a 10 x 34 would make
riding up a hill even "easier", despite requiring twice as many leg
lifts at half the speed. The lower limit for useful uphill bicycle
gearing for normal riders is somewhere down around walking speed.
This is why we just don't see much of the ultra-low gearing setups
that people occasionally wish for on RBT. Bicyclists will try almost
anything, but the extremes usually filter themselves out quickly.

When the North Vietnamese were trundling military supplies south
through mountain trails on heavily-laden bikes, they pushed instead of
trying to fit ultra-low gearing.

I'm open, however, to correction. Does anyone actually have a 20 x 38
on a 700c or MTB? If so, try riding up a trail steep enough to require
it for a few hundred yards one day, and then try pushing the bike up
the same trail again.

Years ago, I watched a pair of ultra-low geared MTB's spinning
furiously up a steep slope in the Wet Mountains and was surprised to
find that I was overtaking them on foot.

Beginning trials riders often re-discover this sort of thing. There's
a limit to how low you can usefully gear a motorcycle, given the
engine characteristics, and the stock trials machines are usually
close to it.

Same thing with the human engine--gear a bicycle too low for too steep
a climb, and you work harder than you would just walking. You'd have
to put a hobble on the hiker's boots to even things up. The Fargo
Street Hill climbers use surprisingly high gearing for their ~30%
grade.

heh heh great image! We used a photo of Vietcong pushing 400lbs of gear
on a Peugeot though the jungle in a Peugeot ad once. lotsa flak. [see
also 'Bicycles in War']

In my experience, most cyclists will prefer a possibly 'inefficient' low
gear to walking. It's a psychological barrier most people simply do not
like to cross. YMMV. I do not have an opinion on what's 'best', having
done both.

Dear Andrew,

I think that we agree about the psychological barrier--most posters on
RBT would automatically strain harder rather than get off and push a
bike, and few of us will give up trying if a pretty girl is watching
or other posters are reading what we write.

But I'm still open to correction.

I just have trouble seeing how moving my feet three feet through an
unnatural high-stepping circle in order to roll myself and my load
forward three feet is going to be easier than ordinary walking.

If I'm wrong, then it should make sense to build a pedal-powered cog
railway with ultra-low gearing up the side of a long flight of steps.

But the cut-off point at which lower gearing doesn't help may be
tricky to determine.

Here's probably the most often reproduced picture of supply bicycles
in Viet Nam:

http://downtheroad.org/Asia/Photo/3Vietnam_Pictures/THUMBS/3War_Remnants_Museum/DSC00102_small.JPG

This picture shows the wooden bracing added to some supply bicycles:

http://www.country-data.com/frd/cs/vietnam/vn01_07h.jpg

Note the lack of a chain on the bicycle in the foreground. (No lower
chain run breaks the white curve of the rear-wheel rim. What looks a
little like a chain is actually the left chain stay.)

And here's a picture showing just how heavily loaded the supply
bicycles were when pushed:

http://tinypic.com/view.php?pic=481wks6

Obviously, bicycles loaded like the ones in these pictures can't be
ridden at all--there's no way to get at the seat or pedals.

Cheers,

Carl Fogel

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

Quoted message said:

On Tue, 10 Apr 2007 20:12:29 -0500, A Muzi <[email hidden]>

Quoted message said:

-snip-

Quoted message said:

<[email hidden]> wrote:
> Try walking up
> one of those Colorado mountains you live near at 3-4 mph while pushing
> a loaded touring bike and then ride up the same stretch at 4 mph.
> Biking up is easier. You may be correct that you actually use less
> energy walking and pushing, but it won't feel like it.

Quoted message said:

Sorry, but I'm not following the logic.
You seem to be saying that "biking up is easier" but it uses more
energy?
As for not feeling like it, walking is if anything more natural than
the circular raise-lower cycle of the pedal. Pedaling at such low
speeds turns a modest hiking slope into a steep stairway.
It might feel better in terms of accomplishment and our natural RBT
prejudice that feet are meant to pedal, not to walk, but if it uses
more energy, it will feel harder, not easier.
Note where such logic would eventually lead--a 10 x 34 would make
riding up a hill even "easier", despite requiring twice as many leg
lifts at half the speed. The lower limit for useful uphill bicycle
gearing for normal riders is somewhere down around walking speed.
This is why we just don't see much of the ultra-low gearing setups
that people occasionally wish for on RBT. Bicyclists will try almost
anything, but the extremes usually filter themselves out quickly.

When the North Vietnamese were trundling military supplies south
through mountain trails on heavily-laden bikes, they pushed instead of
trying to fit ultra-low gearing.

I'm open, however, to correction. Does anyone actually have a 20 x 38
on a 700c or MTB? If so, try riding up a trail steep enough to require
it for a few hundred yards one day, and then try pushing the bike up
the same trail again.

Years ago, I watched a pair of ultra-low geared MTB's spinning
furiously up a steep slope in the Wet Mountains and was surprised to
find that I was overtaking them on foot.

Beginning trials riders often re-discover this sort of thing. There's
a limit to how low you can usefully gear a motorcycle, given the
engine characteristics, and the stock trials machines are usually
close to it.

Same thing with the human engine--gear a bicycle too low for too steep
a climb, and you work harder than you would just walking. You'd have
to put a hobble on the hiker's boots to even things up. The Fargo
Street Hill climbers use surprisingly high gearing for their ~30%
grade.

heh heh great image! We used a photo of Vietcong pushing 400lbs of gear
on a Peugeot though the jungle in a Peugeot ad once. lotsa flak. [see
also 'Bicycles in War']

In my experience, most cyclists will prefer a possibly 'inefficient' low
gear to walking. It's a psychological barrier most people simply do not
like to cross. YMMV. I do not have an opinion on what's 'best', having
done both.

Dear Andrew,

I think that we agree about the psychological barrier--most posters on
RBT would automatically strain harder rather than get off and push a
bike, and few of us will give up trying if a pretty girl is watching
or other posters are reading what we write.

But I'm still open to correction.

I just have trouble seeing how moving my feet three feet through an
unnatural high-stepping circle in order to roll myself and my load
forward three feet is going to be easier than ordinary walking.

Some uneven off-road terrain is easier to roll than walk.

Greg

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

Quoted message said:

Carl, you can easily maintain your balance and still ride up hills at
less than 4 mph.

Seconded. We regularly ride up hills on a tandem at 2.5-3 mph.

cheers,
clive

Here are some further thoughts on why I need a lower gear: 1)In our
local bike group I can always get up steeper hills than other riders
even when they are stronger, when I lend my bike others find the hills
much easier 2)However the problem isn't that I have to spin fast or
fall over-I think a lower gear is needed when I have to slow down my
cadence as it is too hard to pedal. I normally spin at 90 to 100 rpm.
If I got such a low gear that I was spinning faster than that when
ascending a steep hill I would be at the lowest practical gear. But
now as I go up a long steep hill I have to gradually lower my cadence.
If I had the optimal gear I would be able to spin at 90-100 on the
steepest hills with a loaded bike. I have often heard the argument
that with a really low gear you have to turn the pedals faster than is
possible or comfortable, but I think this isn't actually the case. I
have never seen someone be able to keep up even their normal cadence
on a very steep long hill, negating this idea at least for the great
majority of riders.

Quoted message said:

obscenely low gears.

its bottomless!

http://mgagnon.net/velo/pedalier4.en.shtml

carl, what was "rocketman's" name?

seda offers a dog kayak! do you carry bags in a dog kayak?

Quoted message said:

On Tue, 10 Apr 2007 20:12:29 -0500, A Muzi <[email hidden]>

Quoted message said:

-snip-

Quoted message said:

<[email hidden]> wrote:
> Try walking up
> one of those Colorado mountains you live near at 3-4 mph while pushing
> a loaded touring bike and then ride up the same stretch at 4 mph.
> Biking up is easier. You may be correct that you actually use less
> energy walking and pushing, but it won't feel like it.

Quoted message said:

Quoted message said:

Sorry, but I'm not following the logic.
You seem to be saying that "biking up is easier" but it uses more
energy?
As for not feeling like it, walking is if anything more natural than
the circular raise-lower cycle of the pedal. Pedaling at such low
speeds turns a modest hiking slope into a steep stairway.
It might feel better in terms of accomplishment and our natural RBT
prejudice that feet are meant to pedal, not to walk, but if it uses
more energy, it will feel harder, not easier.
Note where such logic would eventually lead--a 10 x 34 would make
riding up a hill even "easier", despite requiring twice as many leg
lifts at half the speed. The lower limit for useful uphill bicycle
gearing for normal riders is somewhere down around walking speed.
This is why we just don't see much of the ultra-low gearing setups
that people occasionally wish for on RBT. Bicyclists will try almost
anything, but the extremes usually filter themselves out quickly.

Quoted message said:

Quoted message said:

When the North Vietnamese were trundling military supplies south
through mountain trails on heavily-laden bikes, they pushed instead of
trying to fit ultra-low gearing.

Quoted message said:

Quoted message said:

I'm open, however, to correction. Does anyone actually have a 20 x 38
on a 700c or MTB? If so, try riding up a trail steep enough to require
it for a few hundred yards one day, and then try pushing the bike up
the same trail again.

Quoted message said:

Quoted message said:

Years ago, I watched a pair of ultra-low geared MTB's spinning
furiously up a steep slope in the Wet Mountains and was surprised to
find that I was overtaking them on foot.

Quoted message said:

Quoted message said:

Beginning trials riders often re-discover this sort of thing. There's
a limit to how low you can usefully gear a motorcycle, given the
engine characteristics, and the stock trials machines are usually
close to it.

Quoted message said:

Quoted message said:

Same thing with the human engine--gear a bicycle too low for too steep
a climb, and you work harder than you would just walking. You'd have
to put a hobble on the hiker's boots to even things up. The Fargo
Street Hill climbers use surprisingly high gearing for their ~30%
grade.

Quoted message said:

heh heh great image! We used a photo of Vietcong pushing 400lbs of gear
on a Peugeot though the jungle in a Peugeot ad once. lotsa flak. [see
also 'Bicycles in War']

Quoted message said:

In my experience, most cyclists will prefer a possibly 'inefficient' low
gear to walking. It's a psychological barrier most people simply do not
like to cross. YMMV. I do not have an opinion on what's 'best', having
done both.

Dear Andrew,

I think that we agree about the psychological barrier--most posters on
RBT would automatically strain harder rather than get off and push a
bike, and few of us will give up trying if a pretty girl is watching
or other posters are reading what we write.

But I'm still open to correction.

I just have trouble seeing how moving my feet three feet through an
unnatural high-stepping circle in order to roll myself and my load
forward three feet is going to be easier than ordinary walking.

Ordinary walking? That is the point I made before. Pushing a 60-100
pound bike up a steep mountain road is not ordinary walking. It takes
far more effort and trouble to push/walk the bike than to ride if your
gear is low enough. Have you ever tried pushing a loaded touring bike
up one of those Colorado mountains you claim to live near? Even the
mild ones of 7% grade. You are bending forward, your achilles tendons
are stretched from bending forward, you are on your toes pushing
forward. Its not ordinary walking.

Carl, someday instead of taking your daily 15 mile trail ride through
the thorns, get a loaded touring bike from someone. Just the bike and
panniers. Put a gallon jug of water in each of the four panniers. 32
pounds total. A light load for loaded touring. Then take this bike
and ride a mile up one of the mountains nearby. Then walk a mile
pushing the bike up the mountain. See which is easier on your legs
and body.

Quoted message said:

If I'm wrong, then it should make sense to build a pedal-powered cog
railway with ultra-low gearing up the side of a long flight of steps.

But the cut-off point at which lower gearing doesn't help may be
tricky to determine.

Here's probably the most often reproduced picture of supply bicycles
in Viet Nam:

http://downtheroad.org/Asia/Photo/3Vietnam_Pictures/THUMBS/3War_Remna...

This picture shows the wooden bracing added to some supply bicycles:

http://www.country-data.com/frd/cs/vietnam/vn01_07h.jpg

Note the lack of a chain on the bicycle in the foreground. (No lower
chain run breaks the white curve of the rear-wheel rim. What looks a
little like a chain is actually the left chain stay.)

And here's a picture showing just how heavily loaded the supply
bicycles were when pushed:

http://tinypic.com/view.php?pic=481wks6

Obviously, bicycles loaded like the ones in these pictures can't be
ridden at all--there's no way to get at the seat or pedals.

Cheers,

Carl Fogel- Hide quoted text -

- Show quoted text -

<[email hidden]> wrote in message
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Quoted message said:

Carl, someday instead of taking your daily 15 mile trail ride through
the thorns, get a loaded touring bike from someone. Just the bike and
panniers. Put a gallon jug of water in each of the four panniers. 32
pounds total. A light load for loaded touring. Then take this bike
and ride a mile up one of the mountains nearby. Then walk a mile
pushing the bike up the mountain. See which is easier on your legs
and body.

My calves hurt just thinking about it :-)

cheers,
clive