More distance per Calorie: Walk vrs Granny Gear Uphill?

[Clive George]

"Tom Keats" <[email protected]> wrote in message
news:[email protected]...

>>> I'll tell ya this much -- I am so sick & tired of
>>> only being able to get 14-28T 6-spd freewheels.
>>> I wish I could get at least a 32.
>>
>> Have a look at building your own just replacing the 28 sprocket with a 32
>> or 34 nicked from a 7 speed Megarange. It'll be slightly thinner but
>> providing you use the six speed spacer it should work fine. You will
>> need two chain whips to disassemble the sprockets off the freewheel body
>> and probably better starting with new rather than trying to disassemble
>> one that has been tightened on by years of use.
>
> I'm talking about ready-to-go, old-style, screw-on
> HyperGlides. You can't take those things apart very
> easily, and when you do, an whole bunch of little
> bearing balls spill out and flow across your floor
> like baby spiders from a cactus that shouldn't have
> been smuggled-in from Mexico.

I've never met a freewheel - yes, the old-style type you're talking about -
where one couldn't remove the sprockets separately.

cheers,
clive

 

[Rob Morley]

In article <[email protected]>, Tom Keats
[email protected] says...
forward motion.
>
> Ah, but when riding a diamond-frame upright bike up a steep hump,
> especially if the bike is heavily rearward laden, the front wheel
> tends to lift up, and a lot of upper body effort is involved in
> just keeping the front wheel down on the ground.

What exactly are you supposed to push against to keep the front wheel
down?

 

[Steve Gravrock]

On 2007-09-09, Rob Morley <[email protected]> wrote:
> In article <[email protected]>, Tom Keats
> [email protected] says...
> forward motion.
>>
>> Ah, but when riding a diamond-frame upright bike up a steep hump,
>> especially if the bike is heavily rearward laden, the front wheel
>> tends to lift up, and a lot of upper body effort is involved in
>> just keeping the front wheel down on the ground.
>
> What exactly are you supposed to push against to keep the front wheel
> down?

You don't push against anything. You pull up on the handlebars, which
has the effect of pulling your upper body down and forward.

 

[[email protected]]

On Sep 8, 2:52 pm, Tony Raven <[email protected]> wrote:
> [email protected] wrote in news:1189282212.500032.53880
> @y42g2000hsy.googlegroups.com:
>
>
>
> > Why would pedaling and putting the power through transmission losses
> > be more efficient/effective/et cetera than just climbing a ladder? How
> > does enforcing a much narrower range of speed and cadence improve
> > things?
>
> Go back and read my previous response to you about upper body movement for
> your answer.
>
> --
> Tony
>
> " I would never die for my beliefs because I might be wrong."
> Bertrand Russell

Dear Tony,

I'm sorry, but it didn't seem very convincing the first time.

The notion that bicyclists are not moving their upper bodies (or, to
be more accurate, using the muscles of their upper bodies) is
strange.

Consider the forces on the handlebars as you chug up a steep slope
with flexed arms.

Or consider trying to chug up that slope with only the tips of your
forefingers touching the bars for insignificant steering movements.

Or replace the metal handlebars with some springs strong enough to
allow steering, but flexible enough to show what kind of forces your
upper body is putting on the bars.

Cheers,

Carl Fogel

 

[Tony Raven]

[email protected] wrote in
news:[email protected]:

> On Sep 8, 2:52 pm, Tony Raven <[email protected]> wrote:
>> [email protected] wrote in news:1189282212.500032.53880
>> @y42g2000hsy.googlegroups.com:
>>
>>
>>
>> > Why would pedaling and putting the power through transmission
>> > losses be more efficient/effective/et cetera than just climbing a
>> > ladder? How does enforcing a much narrower range of speed and
>> > cadence improve things?
>>
>> Go back and read my previous response to you about upper body
>> movement for your answer.
>>
>> --
>> Tony
>>
>> " I would never die for my beliefs because I might be wrong."
>> Bertrand Russell
>
> Dear Tony,
>
> I'm sorry, but it didn't seem very convincing the first time.
>
> The notion that bicyclists are not moving their upper bodies (or, to
> be more accurate, using the muscles of their upper bodies) is
> strange.
>

You misunderstand the physics of the situation. Its nothing to do with
upper body muscle use, its to do with upper body vertical movement (think
potential energy). Lifting your body upwards with every step consumes
energy, having it fall back down at the end of every step doesn't recover
that energy (unlike the downstroke of the pedal under body weight while
standing on the pedals). The energy loss walking will almost certainly
be through the leg muscles having to work harder. As I said, try walking
without having your upper body move up and down.


--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell

 

[Ryan Cousineau]

In article <[email protected]>, [email protected] (Tom Keats)
wrote:

> In article <[email protected]>,
> Tony Raven <[email protected]> writes:
> > [email protected] wrote in
> > news:[email protected]:
> >>
> >> Once the feet travel as far in a circle as they would while walking,
> >> you're at an overall effective 1-to-1 ratio, and it's hard to come up
> >> with an explanation why this would be more effective than pushing the
> >> bike up the same slope with the natural walking motion.

> I'll tell ya this much -- I am so sick & tired of
> only being able to get 14-28T 6-spd freewheels.
> I wish I could get at least a 32.

Change out your 6-speed for a 7-speed Megarange. Unless you currently
have a set of indexed shifters you're loath to switch to the friction
setting, there's no downside.

Or maybe a chain you're very fond of,

--
Ryan Cousineau [email protected] http://www.wiredcola.com/
"I don't want kids who are thinking about going into mathematics
to think that they have to take drugs to succeed." -Paul Erdos

 

[Tony Raven]

[email protected] wrote in news:1189406557.259000.67980
@r34g2000hsd.googlegroups.com:

>
> Unfortunately, the two drive shafts of a bicycle are arranged so that
> they hit top and bottom dead center at the same time, and bicycles
> with freewheels have scarcely any flywheel effect.
>

There was a design of crank where the crank could move a few degrees
relative to the chainwheel so that taking it over TDC was made easier.
They made great claims about efficiency improvements IIRC but they don't
seem to have survived the test of real life.

--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell

 

[Tom Keats]

In article <[email protected]>,
Ryan Cousineau <[email protected]> writes:
> In article <[email protected]>, [email protected] (Tom Keats)
> wrote:
>
>> In article <[email protected]>,
>> Tony Raven <[email protected]> writes:
>> > [email protected] wrote in
>> > news:[email protected]:
>> >>
>> >> Once the feet travel as far in a circle as they would while walking,
>> >> you're at an overall effective 1-to-1 ratio, and it's hard to come up
>> >> with an explanation why this would be more effective than pushing the
>> >> bike up the same slope with the natural walking motion.
>
>> I'll tell ya this much -- I am so sick & tired of
>> only being able to get 14-28T 6-spd freewheels.
>> I wish I could get at least a 32.
>
> Change out your 6-speed for a 7-speed Megarange.

Who's got 'em? Everywhere I've gone when needing to
update my freewheel, only has those steenkin' 6-spd
14-28s. Sometimes I feel like drop-kickin' 'em into
the next universe (or at least, Burnaby.) No doubt
they'd eventually return by similar means.

> Unless you currently
> have a set of indexed shifters you're loath to switch to the friction
> setting, there's no downside.

Heh. I took out the clicks on my thumbies in order to
have friction shifting.

> Or maybe a chain you're very fond of,

I'm not very fond of my current Z Chain. Which is
also all you can get when all you can get is an
all-you-can-get 14-28.

Well, I can always resort to the inner ring if I'd
ever really have to. The middle ring and the 28T
generally gets me up most of the local humps. At
least, the 10%+ ones ;-)

I just dislike the ignominy of having to shift to the
granny ring. Having a 32 or 34 back there while
staying in the middle ring, is comforting to my ego.

And when coming home from a hard-working shift of
hand-bombing freight out of shipping containers,
and subsequently grinding up the South Hill, it'd
be nice to be able to take it a little easy. Maybe
even drop my cadence, and pleasantly mash in somewhat
lower gears a little.


cheers,
Tom

--
Nothing is safe from me.
I'm really at:
tkeats curlicue vcn dot bc dot ca

 

[Peter Clinch]

Clive George wrote:

> Yes, pushing the trike isn't good. So you don't do it.

Was wondering about that, and it struck me that pulling it with a bit of
tape might actually work. It might not, of course, especially if the
steering wants to lock sideways.

> It's a different
> approach - rather than walking, you stop, relax, then ride again. Or
> indeed ride _really_ slowly - which you can, because there's no need for
> balancing.

The only clear problem is the extra time that might involve. I prefer
to get walking rather than wait until I can pedal on, but that's me and
isn't necessarily anyone else...

>
>> I'm trying to figure out if the trike is an advantage or an
>> unnecessary bother on the morning commute.
>
> I think the only way you'll find it out is by trying it. I reckon the
> trike will be less efficient than the bike, but other factors may make
> it more effective for you.

<aol> Yup! </aol>

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Peter Clinch]

Tony Raven wrote:
> Simon Brooke <[email protected]> wrote in
> news:[email protected]:
>
>> Bikes have an effective lower limit speed - the speed at which you can
>> no longer balance and stay upright.
>
> There is another limit which is the ability to keep the front wheel on the
> ground and not loop out backwards.

Assuming you're on one of those ridiculous top-heavy "upright"
contraptions, that is[1]... ;-)

Pete.

[1] though it's never been an issue on the 8 Freight!
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Tony Raven]

Peter Clinch <[email protected]> wrote in
news:[email protected]:
>
> Assuming you're on one of those ridiculous top-heavy "upright"
> contraptions, that is[1]... ;-)

1 million lemmings can't be wrong ;-)

--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell

 

[Tom]

Tom Keats <[email protected]> wrote:
> In article <[email protected]>,
> Ryan Cousineau <[email protected]> writes:
>>
>> Change out your 6-speed for a 7-speed Megarange.
>
> Who's got 'em? Everywhere I've gone when needing to
> update my freewheel, only has those steenkin' 6-spd
> 14-28s.

SJS have them:
http://www.sjscycles.co.uk/cid/PQSK7BAVQ3NCA2I9UEJ2OZ4WYGP2NPMM/category-Freewheels-7-speed-79.htm

Tom
--
Return address is dead. Real address is at
http://www.happy-penguin.info/address.jpg

 

[Roger Merriman]

Julian Gallop <[email protected]> wrote:

> Tony Raven wrote:
> > gary2006uk <[email protected]> wrote in
> > news:[email protected]:
> >
> >
> >>cycling up steep hills is less efficient than walking.ive seen many
> >>mountain bikers riding,legs spinning round,hardly moving,whilst
> >>walking i have also passed bikers on the mountains.ive even seen
> >>cyclists in very low gear on the road,in too low a gear,legs going
> >>round like mad,hardly moving,very innefficient,one turn on my gear on
> >>a racing bike leaves them standing.i think some of them dont want to
> >>put any hard effort into cycling.ive also seen bikers on low gear
> >>dawdling along,no physical effort being used,they cant be benifiting
> >>physicaly in fitness riding that slow.god forbid if they ended up on a
> >>hill on a cycle track.
> >>
> >
> >
> > You've mixed up lots of things that have nothing to do with efficiency
> > and some that do and you have the wrong way round. For example spinning
> > quickly is more, not less, efficient than your "one turn on my gear".
> > Speed has nothing to do with efficiency unless you are starting to go
> > fast enough to introduce air resistance. Those fast spinning cyclists
> > you deride are probably getting up that hill far more efficiently than
> > your wasteful technique.
> >
> I think that when the gear becomes really low, the effort of rotating
> the legs many times over a short distance becomes significant. Whereas
> with walking, the stride length is not decreased very much.
>
> Julian Gallop

no walk up a steep hill and your stride is much less, by steep i mean
30% and over.

you also have to shift your weight, both are done much more automaticly
than on a bike, where one is more aware of it.

roger
--
www.rogermerriman.com

 

[[email protected]]

The book, "Bicycling Science" addresses this exact problem. They try
to figure out at what gradient walking becomes more efficient than
cycling. I think the figure they arrived at was around twenty percent
and they confirmed this with actual evidence--for steep and/or rough
routes, cyclists and runners will frequently take about the same
amount of time to complete the course. If you think about it, as the
grade gets steeper, more and more energy is put into simply overcoming
the force of gravity. Meanwhile, maximum speed drops so that the
raised gearing and lower frictional forces that normally give the
bicycle such an advantage are no longer a factor.

On Sep 6, 7:09 pm, Artemisia <[email protected]> wrote:
> Peter Clinch wrote:
>
> > I recall one incident when a pal and I were taking our MTBs up a fairly
> > steep grassy field. I got bored at walking pace, and decided I'd walk.
> > While walking, I soon overtook my pal, still spinning happily in 1st...
>
> So isn't it actually more efficient energy use to walk uphill than to
> pedal, even if you do have unimaginably low gears and no topple-over on
> a trike?
>
> I'm thinking perhaps the only advantage of trying to pedal up my hills
> is the inconvenience of trying to stand up out of a recumbent...
>
> EFR
> Ile de France

 

[Alan Braggins]

In article <[email protected]>, Tony Raven wrote:
>
>There was a design of crank where the crank could move a few degrees
>relative to the chainwheel so that taking it over TDC was made easier.
>They made great claims about efficiency improvements IIRC but they don't
>seem to have survived the test of real life.

Rotor seems to still be going, though they do make other products
(now including a more conventional crankset).
http://www.roadcyclinguk.com/news/article/mps/UAN/1611/V/1/SP/

Their new stem was announced fairly recently
http://www.roadcyclinguk.com/news/article/mps/UAN/2542/V/1/SP/

Reviews seem to say the dead-spot eliminating cranks do work, but that
it's not clear whether it's worth the extra cost/weight/complexity.
http://www.cyclingnews.com/tech.php?id=tech/2006/reviews/rotor_rsx4_mtb
http://www.bikemagic.com/news/article/mps/UAN/3966/

 

[[email protected]]

On 9 Sep, 09:44, Tony Raven <[email protected]> wrote:
> [email protected] (Tom Keats) wrote innews:[email protected]:
>
>
>
> > Ah, but when riding a diamond-frame upright bike up a steep hump,
> > especially if the bike is heavily rearward laden, the front wheel
> > tends to lift up, and a lot of upper body effort is involved in
> > just keeping the front wheel down on the ground. That's what
> > MTB bar-ends are meant for.
>
> Yes, as I've said multiple times before in this thread, we can all dream
> up scenarios where one is better than the other but the basic starting
> point is still that cycling is more efficient than walking before you add
> in other factors such as steps.....

I don't think you're right, Tony. From experience of being faster on
foot than a cyclist up some hills in the South Downs (and she's fitter
than me), it seems pretty clear that there is a gradient above which
it's more efficient to walk/run. As we were both maxed out in terms of
energy expenditure (we were racing!) that would imply to me that both
efficiency and effectiveness were better for walking.

Also have a look at this article: http://www.springerlink.com/content/bt3tm8ckrjt4fg54/

--

TimP

 

[Ace]

On Mon, 10 Sep 2007 12:15:45 -0000, [email protected] wrote:

>On 9 Sep, 09:44, Tony Raven <[email protected]> wrote:
>> [email protected] (Tom Keats) wrote innews:[email protected]:
>>
>>
>>
>> > Ah, but when riding a diamond-frame upright bike up a steep hump,
>> > especially if the bike is heavily rearward laden, the front wheel
>> > tends to lift up, and a lot of upper body effort is involved in
>> > just keeping the front wheel down on the ground. That's what
>> > MTB bar-ends are meant for.
>>
>> Yes, as I've said multiple times before in this thread, we can all dream
>> up scenarios where one is better than the other but the basic starting
>> point is still that cycling is more efficient than walking before you add
>> in other factors such as steps.....
>
>I don't think you're right, Tony. From experience of being faster on
>foot than a cyclist up some hills in the South Downs (and she's fitter
>than me), it seems pretty clear that there is a gradient above which
>it's more efficient to walk/run. As we were both maxed out in terms of
>energy expenditure (we were racing!) that would imply to me that both
>efficiency and effectiveness were better for walking.

I already pointed out some time ago that my personal experience also
supports this view - I've been in recovery from a serious[1] m/c
accident last year, so earlier this year when I started cycling again
my own drive, which is always a bugger at aroun 28degrees of slope,
was out of the question for me, even on my new mtb with its lowish
granny gear.

I was just physically unable to cycle up the last, steepest bit, at
any time, but could always manage it on foot. When I became fitter I
would try to cycle up most of it, but then I found out that even then
I'd be both quicker and less out-of-breath if I got off and walked.

There are, as always, other factors here, like the degree of
upper-body movement entailed, but overall I was, contrary to my
previous belief, convinced that in some circumstances walking up could
be both faster and less energetic than cycling.

[1] Unplanned back/armco interface at > 50mph - the armco won[2].
[2] Broke 9 ribs, sternum and multiple vertebrae, damaged liver and
collapsed lungs. Apart from that I was fine.
--
Ace in Alsace - brucedotrogers a.t rochedotcom

 

[Tony Raven]

[email protected] wrote in
news:[email protected]:
>
> I don't think you're right, Tony. From experience of being faster on
> foot than a cyclist up some hills in the South Downs (and she's fitter
> than me), it seems pretty clear that there is a gradient above which
> it's more efficient to walk/run. As we were both maxed out in terms of
> energy expenditure (we were racing!) that would imply to me that both
> efficiency and effectiveness were better for walking.
>
> Also have a look at this article:
> http://www.springerlink.com/content/bt3tm8ckrjt4fg54/
>

I've only had time for a very brief scan of the paper but it seems to be
saying there is a small zone in which walking can be more efficient than
cycling. This is at higher gradients and velocities below 1m/s or 2.25mph
(and above 0.1m/s) - a velocity below which most people cannot stay
balanced on a bicycle anyway. Above that speed Fig 2b seems to indicate,
subject to further study, that cycling is the most efficient.

I may change my mind when I've had time to read it properly.


--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell

 

[[email protected]]

On 10 Sep, 15:01, Tony Raven <[email protected]> wrote:
> [email protected] wrote innews:[email protected]:
>
>
>
> > I don't think you're right, Tony. From experience of being faster on
> > foot than a cyclist up some hills in the South Downs (and she's fitter
> > than me), it seems pretty clear that there is a gradient above which
> > it's more efficient to walk/run. As we were both maxed out in terms of
> > energy expenditure (we were racing!) that would imply to me that both
> > efficiency and effectiveness were better for walking.
>
> > Also have a look at this article:
> >http://www.springerlink.com/content/bt3tm8ckrjt4fg54/
>
> I've only had time for a very brief scan of the paper but it seems to be
> saying there is a small zone in which walking can be more efficient than
> cycling. This is at higher gradients and velocities below 1m/s or 2.25mph
> (and above 0.1m/s) - a velocity below which most people cannot stay
> balanced on a bicycle anyway. Above that speed Fig 2b seems to indicate,
> subject to further study, that cycling is the most efficient.
>
> I may change my mind when I've had time to read it properly.

Well, as you wrote before:

Tony Raven wrote:
> Efficiency is normally taken as the energy needed to travel a distance, not
> speed otherwise a Hummer would be classed as more efficient than a bicycle.

Indeed.

The rest of the article describes the most efficient method of
travelling up different inclines. Walking is described as being the
most efficient above ~15%.

 

[Roger Merriman]

Tony Raven <[email protected]> wrote:

> [email protected] wrote in
> news:[email protected]:
> >
> > I don't think you're right, Tony. From experience of being faster on
> > foot than a cyclist up some hills in the South Downs (and she's fitter
> > than me), it seems pretty clear that there is a gradient above which
> > it's more efficient to walk/run. As we were both maxed out in terms of
> > energy expenditure (we were racing!) that would imply to me that both
> > efficiency and effectiveness were better for walking.
> >
> > Also have a look at this article:
> > http://www.springerlink.com/content/bt3tm8ckrjt4fg54/
> >
>
> I've only had time for a very brief scan of the paper but it seems to be
> saying there is a small zone in which walking can be more efficient than
> cycling. This is at higher gradients and velocities below 1m/s or 2.25mph
> (and above 0.1m/s) - a velocity below which most people cannot stay
> balanced on a bicycle anyway. Above that speed Fig 2b seems to indicate,
> subject to further study, that cycling is the most efficient.
>
that would seem to match with my experance. this said the window is
small.

> I may change my mind when I've had time to read it properly.

roger
--
www.rogermerriman.com