Clipless pedals no more efficient than flat?

On 8/13/2020 7:48 PM, John B. wrote:
On Thu, 13 Aug 2020 19:16:34 -0500, AMuzi wrote:

On 8/13/2020 5:52 PM, John B. wrote:
On Thu, 13 Aug 2020 07:22:18 -0500, AMuzi wrote:

On 8/12/2020 9:22 PM, John B. wrote:
On Wed, 12 Aug 2020 21:12:35 -0500, AMuzi wrote:

On 8/12/2020 8:57 PM, John B. wrote:
On Wed, 12 Aug 2020 17:59:20 -0700 (PDT), Frank Krygowski
wrote:

On Wednesday, August 12, 2020 at 8:52:35 PM UTC-4, AMuzi wrote:
On 8/12/2020 6:22 PM, John B. wrote:
On Thu, 13 Aug 2020 06:01:07 +0700, John B.
wrote:

On Wed, 12 Aug 2020 14:54:14 -0700 (PDT), jbeattie
wrote:

On Wednesday, August 12, 2020 at 9:24:50 AM UTC-7, Frank Krygowski wrote:
On 8/11/2020 11:28 PM, jbeattie wrote:
On Tuesday, August 11, 2020 at 6:03:46 PM UTC-7, Frank Krygowski wrote:
On 8/11/2020 6:05 PM, jbeattie wrote:

I certainly pulled up or across the pedal when track racing, and if I pulled out, it could be catastrophic -- and thus double straps and later clipless (some racers used clipless and straps). Foot retention is important when sprinting and climbing out of the saddle. https://www.tandfonline.com/doi/full...0.2020.1769201

It's a shame they didn't test stiff soled cycling shoes with toe clips.
For a long time those were the default choice for avid cyclists. They're
still my choice for long rides.

But I'll point out, that paper (apparently) did not measure efficiency.
The power improvements were huge (9.7???8.7% power gain by adding toe
clips to soft shoes, and 16.6???10.2% gain with rigid shoes and
clipless). On a five percent grade, that corresponds to a very
noticeable increase in speed. If those gains were due to lack of
efficiency of soft soles, those soles must have been soaking up a hell
of a lot of power. That means they should get very hot.

We can discuss this, but I suspect a lot of the gains measured were due
to the "red bikes are faster" effect. Testers were probably
preconditioned to think toe clips help a lot, and REAL cycling shoes and
clipless are what professionals use. That's a recipe for a powerful placebo.

If not that, then what made the power difference? Where would the power
have been previously lost? We should be able to talk about that in detail.

And shoes can make a big difference. I remember going from Detto, Vittoria or Italia (they all blended together) bicycling/bowling shoes of yore with little steel stiffeners and nail on cleats to Duegis with wood soles and bolt-on plastic cleats. https://www.classicsteelbikes.com/wp...-1-600x400.jpg That was huge -- like going from Michelin 50s to Vittoria CGs (I never rode silks). That was probably the single biggest component improvement I ever had.

Again, we should be able to analyze the exact source of the improvement.
The shoes are not a source of power; they are a simple device for
transmitting power from your foot to the pedal.

I don't doubt that some changes allow better biomechanics and thus
better power output. But it's hard for me to see how shoes do that.


A couple of things: (1) your ankle is not a spring, dropping as the sole flexes. Old cycling shoes were really like bowling shoes and not very stiff. (2) Deeper, more secure cleats -- for better or worse. It was not a subtle change for me at all. Others agree: http://stevetilford.com/2016/05/26/cycling-shoes-2/ YMMV.

I'm not surprised that there are people who rhapsodize about shoes. And
I know that certain shoes are more or less comfortable for certain
riders, some shoes have better closure systems, etc. But to return to
_technical_ discussion about power transfer:

Again, the paper you linked could have tested stiff soled shoes with toe
clips. Unfortunately it didn't.

And it's true that "stiff" isn't a binary condition. But aside from
commuting or utility riding, all the cycling shoes I've used (since Bata
Bikers came on the scene) have seemed pretty stiff to me. Not as stiff
as wooden soles, but then, nobody here has identified a mechanism for
power loss through a sole that's a little less stiff.

Thought experiment (since you mention springs): Place a spring with a
high stiffness (say, 100 pounds per inch) on a bike pedal. Place a ten
pound weight on that spring. It will sag 1/10 inch. What's the force on
the pedal?

Repeat with a spring that's less stiff (say, 50 pounds per inch). Place
the same ten pound weight on that spring. It will sag 2/10 inch. What's
the force on that pedal?

The answer is the same in both cases: Pedal force is ten pounds.

It seems pretty simple to me. The power used flexing the sole is not transmitted into the pedal. It is wasted energy. A sloppy shoe-pedal interface is lossy. No? Did you not cinch up your toe-straps before a climb or a sprint?

Rather than trying thought experiments, go and try a pair of stiff shoes in a clipless pedal system. Actually experience the modern world before making grand pronouncement about how nothing makes a difference. And BTW, "pulling up" is not a myth -- as anyone who has pulled out in track sprint can tell you. I almost pulled out of my left shoe last night humping up a hill and had to reach down and cinch up the ratchet -- or if I were you, stop and retie my shoe.

-- Jay Beattie.


If there is a substantial loss of power through "flexing the sole" why
aren't runners wearing hard soled shoes? My guess is that an Olympic
class sprinter is applying at least as much, and possibly more, force
against the ground than a cyclist applies against the pedals. Abebe
Bikila of Ethiopia won an Olympic gold medal in a world-record
2:15:16.2 running barefooted in 1960.

Further to the above, Usain Bolt in breaking the world 100m record
developed a maximum of 2619.5 watts after only 0.89 seconds of the
race.

Not wearing hard soled shoes :-)
--
Cheers,

John B.


Then again Roger Bannister and runners of his era and before
ran in 'running flats', thin very light leather shoes with
leather soles.

And there's been the recent trend of barefoot running.

It may well be that, just like flat or engaged pedals,
humans adapt well to many variants. Crank length seems to be
similar as there aren't objective performance differences
despite rider perception.

Indeed, we're probably the most adaptable animal species ever.

- Frank Krygowski

Perhaps because we aren't "specialized".

A lion can run incredibly fast, about 50 MPH,for a short distance.
Because that is how he gets supper, (actually she gets supper) but
can't climb trees. A Monkey isn't very fast on the flat but scurries
up trees quickly. A human is slower then a lion in a sprint and can't
climb trees as well as the monkey but can do both.

meh.
'We have the Maxim and they have not.'

By "maxim" I assume that you mean Sir Hiram Stevens Maxim's invention
rather than the synonym for "axiom".
--
Cheers,

John B.


It's a quotation and yes it's capitalized.

:-) Ah yes, the complete quotation is,
"Whatever happens, we have got
The Maxim gun, and they have not. "

And did apparently apply to Sir Hiram's invention.

I suppose in modern terms it would read something like "And, we got
more atom bombs then they do" :-)
--
Cheers,

John B.


Back to your point, yes monkeys climb trees better and a
lion's sprint is formidable, but we became the dominant
species for a different set of features and adaptability is
high among them.

Adaptability? In what manner? Mankind doesn't adapt, in any real
sense, to outside events, they simply learn to live in those
circumstances.

.... or perhaps I'm wrong. A day or so ago I researched the *average*
weight of the USian female and discovered that the average weight is
170.6 pounds and the average height is 5'4".

Apparently the average USian IS adapting to McDonalds :-)
--
Cheers,

John B.

Q. E. D.


--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

Ralph Barone writes:

John B. wrote:
On Thu, 13 Aug 2020 14:49:36 +0000 (UTC), Ralph Barone
wrote:

IJohn B. wrote:
On Thu, 13 Aug 2020 02:36:27 +0000 (UTC), Ralph Barone
wrote:

Frank Krygowski wrote:
On Wednesday, August 12, 2020 at 5:54:17 PM UTC-4, jbeattie wrote:
On Wednesday, August 12, 2020 at 9:24:50 AM UTC-7, Frank Krygowski wrote:
I'm not surprised that there are people who rhapsodize about shoes. And
I know that certain shoes are more or less comfortable for certain
riders, some shoes have better closure systems, etc. But to return to
_technical_ discussion about power transfer:

Again, the paper you linked could have tested stiff soled
shoes with toe
clips. Unfortunately it didn't.

And it's true that "stiff" isn't a binary condition. But aside from
commuting or utility riding, all the cycling shoes I've used
(since Bata
Bikers came on the scene) have seemed pretty stiff to me. Not as stiff
as wooden soles, but then, nobody here has identified a mechanism for
power loss through a sole that's a little less stiff.

Thought experiment (since you mention springs): Place a spring with a
high stiffness (say, 100 pounds per inch) on a bike pedal. Place a ten
pound weight on that spring. It will sag 1/10 inch. What's the force on
the pedal?

Repeat with a spring that's less stiff (say, 50 pounds per inch). Place
the same ten pound weight on that spring. It will sag 2/10 inch. What's
the force on that pedal?

The answer is the same in both cases: Pedal force is ten pounds.

It seems pretty simple to me. The power used flexing the sole is not
transmitted into the pedal. It is wasted energy. A sloppy shoe-pedal
interface is lossy. No? Did you not cinch up your toe-straps before a
climb or a sprint?

"It seems pretty simple to me" should be a warning. Imagine Joerg
saying that about a legal issue.

To give you a hint of the complexity, you've conflated "power" and
"energy." ("Force" and "work" are other such quantities. All are
related but not identical; all are used colloquially.)

So, how would an engineer calculate - at least roughly - the energy
lost due to sole flex? It would be the product of the force applied
and the (extra) distance it moves. Seems to me we're talking a distance
of a tiny fraction of an inch, and probably a microscopic loss. As I
hinted earlier, if that energy were lost by soaking into the shoe
structure, it would be converted to heat energy. It would be detectable
by an increase in temperature. But when I commuted to work, my office
shoes never seemed to get hot!


Frank, what you are missing is that you don?t always need to waste energy
in order to not put out as much power. I dare you to put out as much power
riding barefoot as you would with shoes. Most riders with most pedals would
find their power dropping, not due to energy wastage, but just because it
would hurt to ride barefoot.


I really wonder. Back when I was a young lad I rode a bicycle
barefooted for much of the summer. Granted that "Summer" in upstate
New Hampshire doesn't last that long but still...
--
Cheers,

John B.



IÂ’m sure weÂ’ve all rode barefoot or with minimal footwear at
one time or
another. The question is “Were you at the head of the peloton while doing
so?”


Oh! I hadn't realized that the discussion pertained only to those few
who were capable of riding at the head of the peloton.
--
Cheers,

John B.

John, I’m not sure how you manage to find the time to purposely
misunderstand everything that other people say. Retirement must be nice.

Evidently one can adapt himself to it.

Ralph Barone writes:

John B. wrote:
On Fri, 14 Aug 2020 01:02:54 +0000 (UTC), Ralph Barone
wrote:

John B. wrote:
On Thu, 13 Aug 2020 14:49:36 +0000 (UTC), Ralph Barone
wrote:

IJohn B. wrote:
On Thu, 13 Aug 2020 02:36:27 +0000 (UTC), Ralph Barone
wrote:

Frank Krygowski wrote:
On Wednesday, August 12, 2020 at 5:54:17 PM UTC-4, jbeattie wrote:
On Wednesday, August 12, 2020 at 9:24:50 AM UTC-7, Frank
Krygowski wrote:
I'm not surprised that there are people who rhapsodize about
shoes. And
I know that certain shoes are more or less comfortable for certain
riders, some shoes have better closure systems, etc. But to return to
_technical_ discussion about power transfer:

Again, the paper you linked could have tested stiff soled
shoes with toe
clips. Unfortunately it didn't.

And it's true that "stiff" isn't a binary condition. But aside from
commuting or utility riding, all the cycling shoes I've used
(since Bata
Bikers came on the scene) have seemed pretty stiff to
me. Not as stiff
as wooden soles, but then, nobody here has identified a mechanism for
power loss through a sole that's a little less stiff.

Thought experiment (since you mention springs): Place a spring with a
high stiffness (say, 100 pounds per inch) on a bike
pedal. Place a ten
pound weight on that spring. It will sag 1/10 inch. What's
the force on
the pedal?

Repeat with a spring that's less stiff (say, 50 pounds per
inch). Place
the same ten pound weight on that spring. It will sag 2/10
inch. What's
the force on that pedal?

The answer is the same in both cases: Pedal force is ten pounds.

It seems pretty simple to me. The power used flexing the sole is not
transmitted into the pedal. It is wasted energy. A sloppy shoe-pedal
interface is lossy. No? Did you not cinch up your toe-straps before a
climb or a sprint?

"It seems pretty simple to me" should be a warning. Imagine Joerg
saying that about a legal issue.

To give you a hint of the complexity, you've conflated "power" and
"energy." ("Force" and "work" are other such quantities. All are
related but not identical; all are used colloquially.)

So, how would an engineer calculate - at least roughly - the energy
lost due to sole flex? It would be the product of the force applied
and the (extra) distance it moves. Seems to me we're talking a distance
of a tiny fraction of an inch, and probably a microscopic loss. As I
hinted earlier, if that energy were lost by soaking into the shoe
structure, it would be converted to heat energy. It would be detectable
by an increase in temperature. But when I commuted to work, my office
shoes never seemed to get hot!


Frank, what you are missing is that you don?t always need to waste energy
in order to not put out as much power. I dare you to put out as
much power
riding barefoot as you would with shoes. Most riders with most
pedals would
find their power dropping, not due to energy wastage, but just because it
would hurt to ride barefoot.


I really wonder. Back when I was a young lad I rode a bicycle
barefooted for much of the summer. Granted that "Summer" in upstate
New Hampshire doesn't last that long but still...
--
Cheers,

John B.



I?m sure we?ve all rode barefoot or with minimal footwear at one time or
another. The question is ?Were you at the head of the peloton while doing
so??


Oh! I hadn't realized that the discussion pertained only to those few
who were capable of riding at the head of the peloton.
--
Cheers,

John B.

John, IÂ’m not sure how you manage to find the time to purposely
misunderstand everything that other people say. Retirement must be nice.

How so? You ask "Were you at the head of the peloton while doing
so?" apparently referring to my comment about riding barefooted as a
youth.

I reply that I hadn't realized that were talking about those few
capable of riding at the head of the peloton.

And I misunderstood?

I might add that I grew up in a small village in New Hampshire where,
probably, half the population spoke, or at least understood, French
and I never heard of a "peloton" while growing up.

--
Cheers,

John B.

I’m fairly certain that you understood my original comment perfectly well
and are just yanking my chain because there’s nothing better for you to do
today, but what the hell, let me explain.

The discussion was on the topic of whether stiffer shoes and clips
translated into higher power at the cranks. Remember that, because the rest
^^^^^
I think this may be the point at which minds ceased to meet. Some
people (Mr. Krygowski?) continued to argue about *efficiency*, which is
a different kettle of red herrings. Put a pea inside the shoe and under
the forefoot of a cyclist, even a non-princess, and maximum power output
will markedly decline. Efficiency will likely be unaffected, it might
well increase.

Human beings are not mechanical motors, comfort and familiarity play a
role in how much power we can produce. Put Mr. Slocum barefoot on a rubber
pedaled bike today and I'll bet he goes a lot slower than he's used to.

of the conversation depends on that context. Frank was saying that he
didn’t believe it and I was arguing that a stiffer sole meant that you
could put more pressure on the pedal without discomfort, and to make the
point easier to visualize, I made the extreme example of riding barefoot.
You then chimed in about riding barefoot in the halcyon days of your youth.
At that point, I replied, still within the context of whether a stiffer
shoe could result in higher power at the crank, that essentially anybody
could pootle along barefoot on a bike, but the effect I was hypothesizing
would only be noticeable at extreme efforts, therefore unless you were at
the head of the peloton, your barefoot bicycling experience was of no
significance to the conversation.

PS: you may not have known the word peloton when you were a shoeless youth,
but you damn well know it now, so whether or not you ever heard the word
peloton in your youth is again, immaterial to the discussion.

This cantankerous man will now do something other than argue with random
people on the internet.


--

On Monday, 10 August 2020 21:49:48 UTC-4, bob prohaska wrote:
I found this not-entirely-ancient video,
https://www.youtube.com/watch?v=KUEaN9FKGLE
which posits that there's no efficiency gain
using clipless (or traditional toe-clips) in
terms of rider performance.

That's a considerable surprise. It certainly
_felt_ more efficient to use clips/straps,
and then Shimano SPDs, compared to flat pedals.

Am I a victim of self-deception? Or worse yet,
marketing?

Thanks for reading,

bob prohaska

Put a high cleat plate like what's on a Shimano 600 pedal with toe-clips, and ride it with a flexible/soft-sole shoe and then ride the sme setup but with a stiff sole shoe and you'll notice quite a bit of difference in the amount of pressure you can apply to the pedal on the downnstroke. I think that makes pedaling much more efficient as you;re not so tired/sore after X-number of pedal revolutions.

Cheers

On 8/14/2020 5:03 PM, Radey Shouman wrote:
Ralph Barone writes:

The discussion was on the topic of whether stiffer shoes and clips
translated into higher power at the cranks. Remember that, because the rest
^^^^^
I think this may be the point at which minds ceased to meet. Some
people (Mr. Krygowski?) continued to argue about *efficiency*, which is
a different kettle of red herrings.

Well, as the title of the thread indicates, efficiency was the start of
the discussion. And yes, efficiency is a different quantity than power
output - a point I made much earlier.

But even the video originally linked by Bob
https://www.youtube.com/watch?v=KUEaN9FKGLE
may have started conflating things. At about 0:55 he says the clipless
pedals don't seem to contribute toward "work done." Work is yet another
different, but related, quantity.

Put a pea inside the shoe and under
the forefoot of a cyclist, even a non-princess, and maximum power output
will markedly decline. Efficiency will likely be unaffected, it might
well increase.

Human beings are not mechanical motors, comfort and familiarity play a
role in how much power we can produce.

I agree. But if that's what's being discussed, we need a study comparing
comfortable vs. uncomfortable shoes and pedals. That's not the same as
clipless vs. toe clips vs. flat pedals.

Our fairly short ride today was more of a utility ride (getting takeout
food at a suburban deli) but we did suit up (it was hot!) and I used my
new cycling shoes with toe clips. My feet were perfectly comfortable.

BTW, since this discussion had me paying attention, I noticed with a bit
of surprise that I do "ankle" to a degree. I didn't realize I still did
that. But I never detected any pulling up. Maybe some minor unweighting
of the rear pedal on occasion, but never a true upward force.

--
- Frank Krygowski

Frank Krygowski wrote:
On 8/14/2020 5:03 PM, Radey Shouman wrote:
Ralph Barone writes:

The discussion was on the topic of whether stiffer shoes and clips
translated into higher power at the cranks. Remember that, because the rest
^^^^^
I think this may be the point at which minds ceased to meet. Some
people (Mr. Krygowski?) continued to argue about *efficiency*, which is
a different kettle of red herrings.

Well, as the title of the thread indicates, efficiency was the start of
the discussion. And yes, efficiency is a different quantity than power
output - a point I made much earlier.

But even the video originally linked by Bob
https://www.youtube.com/watch?v=KUEaN9FKGLE
may have started conflating things. At about 0:55 he says the clipless
pedals don't seem to contribute toward "work done." Work is yet another
different, but related, quantity.


At the risk of adding another herring to the (already overfull) pot,
when I watched the video and posted the link my thoughts centered on
_ergonomic_ efficiency. It seemed pretty obvious that spreading work
over more muscles makes it easier on the muscles. It certainly _feels_
correct. That's really the crux of the "have I been misled" question.

It's been an interesting exchange, thanks to everyone for posting!

bob prohaska