Hills killing me

[The Pomeranian]

Robert Chung wrote:
>
> "The Pomeranian" <[email protected]> wrote
> >
> > Robert Chung wrote:
> > >
> > > When Jean Nuttli tried the hour record last November, he used a 57x15,
> which
> > > was chosen so that he could break the record at 105rpm. In falling 2km short, he averaged
> > > 99rpm.
> >
> > I don't know why all these different riders throughout time are using a gear that achieves a
> > similar cadence, but it seems eerie.
>
> It only seems eerie at first. Do you think that Nuttli should have been using a different gear?

I wouldn't pretend to know.

> He was obviously targeting a gear that would get him to 49km at 105rpm. BTW, while he didn't break
> Boardman's (or Merckx's) record, he went farther than Coppi did, and farther than Anquetil's 1956
> record -- he also came close to Anquetil's (disallowed) 1967 record. This is all to say that
> Nuttli wasn't some complete clown. Anyway, I'd say he was power-limited, not cadence or
> gear-limited.

Since he couldn't put out enough power at 105 rpm, and had a fixed gear, his only possiblity was to
slow down. That isn't explicitly necessary for multi speeds, where you can change the gear. What if
he could only put out 400 watts at 105 rpm but could put out 420 watts at 90 rpm? (This small power
difference would probably produce very little net speed difference up around 33 mph.)

> > So for a climb test, I would pick the same climb, the same start, and the same finish, and same
> > bike. I would have closely spaced gears and I would have gears I could turn up to 100 rpm or so,
> > since I pedal that fast on level ground commonly -- it has to be tested to know and you need to
> > have the gears *first* to do the test. I would do the climb at constant cadences +/-5% at (say
> > for starters) 70, 80, 90, 100 rpm, simply shifting to stay in range. I would time the results
> > and repeat the tests over and over, many times. The time and the constant climb and equipment
> > amount to a comparative power meter.
>
> Sorry, I should have been clearer. I didn't just mean the test procedures, though that's certainly
> of interest and if you'd left it out I very well may have asked it next. I meant, what is the
> hypothesis that you'd be testing?

This specific purpose would be to find out how to obtain the highest average power possible for the
course, with the independent variable being cadence.

> Are you hypothesizing that power is higher at one cadence than another?

Since there is a near torque stall at the low end, and certainly an upper bound on cadence too (try
doing a 1 hour TT at 160 rpm and then at 100 rpm and see which gives the best time), I *know* that
power cannot possibly be constant and I know it must "hump" at least once between these extremes. I
know it "peaks" at least once. The question is whether it peaks in any manner significant enough to
be concerned about.

> If so, then I can see why you'd think to do the test that you described, and why you'd think it
> tedious. I agree, those would be very tedious experiments but more than that I fear they would not
> only be tedious but also not particularly conclusive. I think in another thread I once asked if
> you'd ever seen any power data files. You didn't answer that then, but I'm presuming from your
> responses that you haven't. If you'd worked much with power data files you'd understand why I
> think that experiment would be inconclusive, but basically I think that that particular hypothesis
> (if it is the one you'd intended) isn't well-formed. If you work on the hypothesis a bit you can
> cut down on the tediousness a lot; but I'm still not sure about the conclusiveness.
>
> Why wouldn't you look at some of the other evidence that's available, first? To be frank (as
> opposed to being Frank) I'd start by googling for "cycling power data files." I haven't been able
> to find many data files but this is a good start. Since you appear to have a well-developed
> scepticism about things, I'd recommend ignoring the analytical pieces, analyzing the data you find
> yourself, and reporting back here.
>
> To lay my cards on the table, I think you're right about gears. I think you're wrong about
> the reason. But look at the data first. Perhaps the hour-record cadence thing won't seem
> quite as eerie.

 

[The Pomeranian]

[email protected] wrote:
>
> The who? writes anonymously:
>
> > I was no racer, but I liked going fast down Bonny Doon Road and at the little downhill by
> > Pelican Rock on Highway 1. It was always a challange to see if I could pop 50 mph out. Now to
> > pop the 50 mph out, I tried to maintain my speed on the flatter sections and "sprint" into
> > the steep sections with as much speed as possible. I supposed that would give me a better
> > chance to (tuck in and) achieve terminal velocity in the steep sections, since they aren't
> > infinitely long.
>
> Unfortunately you were thinking with your gluteus maximus instead of looking at a speedometer now
> and then or you would have noticed that you can reach terminal velocity from Bonny Doon regardless
> of initial speed and that pedaling requires not getting in a tight crouch and uses up more energy
> than the crouch gains.

That is pretty much what I discovered in practice. I didn't have an education in the sciences at the
time but I figured the same thing out by simply experimenting. Also, I wasn't only trying to just
hit 50, I was trying to see how fast I could get down the hill. That means I was doing both a lot of
pedaling and tucking. Boony Doon has plenty of sections you need to pedal on if you want to get down
the hill fast. In short, I was dissatisfied with a 53x13.

> Even down 40mph descents, like the west slope of HWY9 toward Santa Cruz is faster just coasting
> than all the pedaling with a macho big gear can produce.

Not entirely true. There are many sections to pedal on, even if it is only a 5 second turn of
the pedals.

> Incremental speed of 1mph at 40mph requires 8x the power that 1mph increase does at 20mph.
> Realizing that, you ought to be able to draw the conclusion that for anything but a sprint of a
> few seconds,...

And I did say sprint. One can put out very high power bursts if they don't do it too often.

> ...pedaling is utterly useless at higher speeds, especially above 40mph. The longer the hill the
> more wasteful and slower it is.

Re-think that one. Descents aren't always some homogeneous constant slope with no turns (to be
accelerated out of), and never any strong tailwinds. Moreover, the cause is not always to simply
reach terminal velocity, sometimes it is elapsed time to the bottom (catching or staying away from
other racers); more physical effort than that simply needed to achieve terminal velocity is more
often distinctly necessary. That doesn't say there still won't remain a lot of tucking and coasting.
Your ideal is only partly correct.

 

[Tom Nakashima]

Jobst, I can't help but think of the 1986 Tour de France, when LeMond & Hinault were hitting speeds
of 60+ mph on the slopes of the Pyrenees. Viewing the tape, they were at times pedaling in unison on
the straights and relaxing in the turns, pure poetry in motion. -tom

<[email protected]> wrote in message news:XH4%[email protected]...
>
> Incremental speed of 1mph at 40mph requires 8x the power that 1mph increase does at 20mph.
> Realizing that, you ought to be able to draw the conclusion that for anything but a sprint of a
> few seconds, pedaling is utterly useless at higher speeds, especially above 40mph. The longer the
> hill the more wasteful and slower it is.
>
> Jobst Brandt [email protected] Palo Alto CA

 

[Peter Headland]

As I have observed previously, I ride what pleases me. When I got my new bike last year, it came
with a Shimano 12-27 cassette (which means no 16t sprocket). I had not owned a bike with such
closely-spaced gears for well over 25 years. I certainly didn't imagine that the 15-17 step would be
annoying (in fact, I confess to feeling a great deal of scepticism when I saw posters in the past
here bemoaning the lack of a 16t).

However ... over a couple of thousand miles' riding, I slowly became aware that I was
sometimes "hunting" between 15t and 17t, comfortable in neither. I also noticed that whenever
I shifted and thought "ouch, that was a big step - did I shift two cogs by mistake?) it was
the step from 15 to 17.

Now, maybe the marketing people are more cunning and subtle than I think, but I would respectfully
suggest that the above represents a genuine preference on my part for single tooth steps. Nothing to
do with any theories about power or efficiency, just what "feels right" to me.

Feel free to tell me I am a fool, a dupe, immoral, devil's spawn, not fit to own a bike, etc. Or
even to patiently explain to me that I am wrong, imagining things, wasting my money (I bought a
12-23, but am vaguely considering switching to Campy 10v to get the big sprocket back).

 

[Chris Butler]

On Mon, 03 Feb 2003 02:46:56 GMT, [email protected] wrote:

>Ben Kaufman writes:
>
>>> Incremental speed of 1mph at 40mph requires 8x the power that 1mph increase does at 20mph.
>>> Realizing that, you ought to be able to draw the conclusion that for anything but a sprint of a
>>> few seconds, pedaling is utterly useless at higher speeds, especially above 40mph. The longer
>>> the hill the more wasteful and slower it
>>> is.
>
>> Isn't it the square of the velocity making it 4x? My reasoning is that the force of wind
>> resistance is square of velocity, work is force over distance and power is work over time.
>
>No. Drag increases as the square of velocity and power, therefore, as the cube for the reason
>you give.

Therefore rate of change of power with velocity increases as the square of velocity (P=k*V^3
therefore dP/dV=3*k*V^2). So an incremental speed of 1mph at 40mph requires only 4x the power that
1mph increase does at 20 mph.

--

Chris Butler

 

[The Pomeranian]

Frank Krygowski wrote:
>

> Many, many years ago, I moved from one area of the country (where I'd done well in a couple
> low-level races) to a bigger city with a real bike club. I never really thought of myself as fast,
> so when I saw a series of training rides in the schedule, I was tempted, but scared - partly
> because of the "no stops, no wimps" phrase in the description.

It's probably good to warn people that there is no stopping and waiting. The "wimps" part ought to
be dispensed with. One thing I liked about the Santa Cruz ride is that no one "owns it." It is
simultaneously well established yet free for all. There are no affiliations of any kind. Social
rules and cycling etiquette alone provide feedback and regulation.

> I had little money at that point, and very little free time. The biggest part of my riding was
> commuting to work (then as now). But I eventually decided to give the training ride a try. I took
> off my fenders and my rear rack. I left my handlebar bag on, though.
>
> It was a bit of an intimidating experience. I was the only guy on clincher tires, from what I
> could see. Almost everyone was running Campy derailleurs and corncobs, talking equipment and
> talking grams. I had a SunTour derailleurs shifting a 14-34 freewheel and half-step chainrings. My
> legs had hair on them.
>
> The "leader" came over and said "Well, we're just taking highway *** down to YYY town. It's just
> an out-and-back. You can turn around and come back whenever you like." Gee, thanks.
>
> We started off and stayed together pretty well as a group. I wasn't at all confident, so I was
> being careful not to push too much. I remember making a crack about one friend in front of me,
> when he missed a shift with his Campy. But most of us stayed well together. I was a bit surprised
> that some guys fell back on some slight climbs, but they weren't too far off, less than 100 yards.
>
> At the turn-around, we swept into a big parking lot then headed back north. I just happened to be
> closer to the north exit, so I was among the first five guys, maybe 50 yards ahead of the rest,
> when we pulled out. I was surprised when the two guys in front jumped. Three more of us just
> managed to hang on to catch them. I was pretty anaerobic at that point, but I settled down within
> the five-man pace line.
>
> It wasn't what I consider a good pace line. It wasn't the "let's work together, front guy rotates
> back" sort. Instead it was more like "I can pull faster than you can, and I'm going to sprint from
> the back of the line to prove it." Backwards rotation. But we hung together for a long while. The
> rest of the group was way behind by now.

What I do when someone wants to prove how strong they are is: let them prove it. Tell them you won't
work until they stop riding like retards (maybe a little different terminology, however). At the
Santa Rosa Tuesday Night series this past year, I was shocked at how crappy people sometimes worked
together. Likewise I was shocked while in some breaks that guys would let me just sit on the back
and miss pull after pull without complaining. For me, I would try to guilt another rider into taking
pulls, even if I knew I was stronger. Where I am from (Santa Cruz), disruptive paceline riders get
instructions from the more experienced riders.

> I tried pulling several times, but they wouldn't let me pull for long. It wasn't that I was any
> slower - I guess they didn't like looking at my hairy legs. In particular, the 18-year-old with
> the fast reputation seemed to jump to the front very soon after I started pulling.

I do as I said before. You shouldn't be on the front for very long with 5 person line, imo. If
someone treats you poorly for hairy legs it says something about them, not you. But I can tell you
that chicks dig shaved legs, and so there is a very good technical reason to shave.

> Finally, on one rise, he again pulled out to pass, and kicked the pace up. I barely hung on as he
> came around. Nobody else did. He and I were off the front, and I was working hard to pump air into
> my lungs. I remember saying "You want me to pull?" (I sure wasn't going to try to pass him) but he
> just kept his head down. I shrugged and hung on.

Like an experienced and talented rider said once to me: "if someone wants or decides to pull, let
them." I wouldn't give it a second thought. I've compensated for at least some of my deteriorating
ability with simple patience.

> That was it for the last mile or so, including the uphill finish. Neither of us tried to sprint. I
> was happy to be alive. Coming in second was fine with me.
>
> The other guys came in, saying things like "I just didn't have it when we hit that hill" and "We
> didn't know you were going to take off like that. Then we couldn't catch you." The 18-year-old
> said some kind words, and the "leader" came over as I put my bike back onto my roof rack, saying
> "You did really well! You know, you ought to get a racing bike!"
>
> Meanwhile, everyone else was sort of quietly ignoring me, as in "That didn't really happen." I
> heard several of them talking about their brands of tires.

At least someone talked to you and gave you genuine credit. Training rides with a lot of people are
like anything, not everyone has a rapport with everybody else, and some people are simply
introverted and only talk to people they already know. Like anywhere, cliques can exist. As an
atheletic endeavor, the most talented and most familiar tend to get the most attention, for right or
wrong. I wasn't "friends" with all that many people, despite the fact that the Saturday Ride could
have upwards of 100 people sometimes. Mostly, I would refer to many of people as aquaintances, not
friends. I would never see most folks aside from the ride and that was okay with me and apparently
with them also.

I did end up with making a couple close friends that I would have not made if I was too put off by
the fact that nobody bothered to talk to me at first and had stopped going on the rides. So I view
it as quite positive overall.

> BTW, on a different ride, the 18-year-old once told me about his new freewheel. Something like 100
> grams lighter. I asked if he thought he could feel that difference in mass, and he assured me he
> _definitely_ could.

I too am quite skeptical that he could "feel it" in an immediate sense. One of those good friends I
did make really believes that "something happens" to steel frames after a few years. I told him from
what I learned in Materials Science that would be not true if the cycles were a bit under plastic
yield. So I think my belief is based in science, and his isn't, but I can easily overlook this
trivial matter because he's a lot more of good guy overall than he is misinformed about steel.

 

[Jobst Brandt]

Tom Nakashima writes:

> I can't help but think of the 1986 Tour de France, when LeMond & Hinault were hitting speeds of
> 60+ mph on the slopes of the Pyrenees. Viewing the tape, they were at times pedaling in unison on
> the straights and relaxing in the turns, pure poetry in motion.

60mph is generally a figment of Phil Liggett's imagination. 60mph is not possible on most tour
classics, be that TdS, GdI or TdF. Typically, in all of Bob Roll's racing, he only once reached
100km/h and that event is what caused him and Alcala to block the next stage start in protest to
the crash that was caused; the stage start in question having been down the descent that reached
this speed.

Ligget cavalierly describes the 7-8% descent of the twisty Galibier as 60mph when all riders are
pedaling continuously except in corners. The public has been led to believe these tales having hear
them so often. I recall being credited with a 60mph descent in a Berkeley Hills race on a section
that even 45mph is only possible with favorable wind. Of course back then we had no Cyclometers and
could not verify that these were lies.

Consider that increasing speed of 1mph at 60mph takes about 13.8 times the power of doing so at
25mph. Pedaling at over 40mph is useless, and what you saw was probably at less than 40 if it wasn't
a short burst for a finish line, in spite of the announcers BS.

Thats (60/25)^3 = 13.824

Jobst Brandt [email protected] Palo Alto CA

 

[Jobst Brandt]

Tom Nakashima writes:

> I can't help but think of the 1986 Tour de France, when LeMond & Hinault were hitting speeds of
> 60+ mph on the slopes of the Pyrenees. Viewing the tape, they were at times pedaling in unison on
> the straights and relaxing in the turns, pure poetry in motion.

60mph is generally a figment of Phil Liggett's imagination. 60mph is not possible on most tour
classics, be that TdS, GdI or TdF. Typically, in all of Bob Roll's racing, he only once reached
100km/h and that event is what caused him and Alcala to block the next stage start in protest to
the crash that was caused; the stage start in question having been down the descent that reached
this speed.

Ligget cavalierly describes the 7-8% descent of the twisty Galibier as 60mph when all riders are
pedaling continuously except in corners. The public has been led to believe these tales having heard
them so often. I recall being credited with a 60mph descent in a Berkeley Hills race on a section
that even 45mph is only possible with favorable wind. Of course back then we had no Cyclometers and
could not verify that these were lies.

Consider that increasing speed of 1mph at 60mph takes about 13.8 times the power of doing so at
25mph. Pedaling at over 40mph is useless, and what you saw was probably at less than 40 if it wasn't
a short burst for a finish line, in spite of the announcers BS.

Thats (60/25)^3 = 13.824

Jobst Brandt [email protected] Palo Alto CA

 

[The Pomeranian]

Terry Morse wrote:
>
> I've done some informal hill climbing experiments, where I rode up a 7% grade in different gears
> while maintaining a heart rate of 160-165. At 50, 60, and 75-80 rpm, my speed was essentially the
> same. The gearing made no difference at all.

I have some questions:

1. What actual gearing did you have on your bike
2. What was the road/route specifically
3. What is your max heart rate

 

[Robert Chung]

"The Pomeranian" wrote:
> Since he couldn't put out enough power at 105 rpm, and had a fixed gear, his only possiblity was
> to slow down. That isn't explicitly necessary for multi speeds, where you can change the gear.

Right, and that's one of the reasons why looking at the hour-record cadences is a dead-end despite
what you wrote a few messages upthread.

> > > So for a climb test, I would pick the same climb, the same start, and the same finish, and
> > > same bike. I would have closely spaced gears and
I
> > > would have gears I could turn up to 100 rpm or so, since I pedal that fast on level ground
> > > commonly -- it has to be tested to know and you need to have the gears *first* to do the test.
> > > I would do the climb
at
> > > constant cadences +/-5% at (say for starters) 70, 80, 90, 100 rpm, simply shifting to stay in
> > > range. I would time the results and repeat the tests over and over, many times. The time and
> > > the constant climb and equipment amount to a comparative power meter.
> >
> This specific purpose would be to find out how to obtain the highest average power possible for
> the course, with the independent variable being cadence.

Hmmm. Have you had any experience designing experiments and testing hypotheses? BTW, for the
experiment as you've described it, you don't need a power meter. All you need is a cyclecomputer
with a cadence sensor and a stopwatch. If you're willing to do some paper-and-pencil work before you
start you don't even need a cadence sensor, just your speedometer and a little table to tell you
when your speed for a particular gear is out of range. Anyway, I would think that a flaw of this
particular experiment is that if you don't find an effect (or you find a confusing effect like two
peaks) you wouldn't know if you simply weren't accurate enough to detect the effect or if you were
actually disproving your hypothesis. I've already tipped my hand that I think your hypothesis is
ill-formed which is why I think you'll have difficulty coming to conclusions. But go ahead, have at
it.

In the meantime, since you've said that you know how to analyze data (which makes your reticence to
look at any even more puzzling) I'd suggest again that you and Terry and Frank, if they're still
reading this thread, look at the data that are already available.

> > Why wouldn't you look at some of the other evidence that's available,
first?
> > To be frank (as opposed to being Frank) I'd start by googling for
"cycling
> > power data files." I haven't been able to find many data files but this
is a
> > good start. Since you appear to have a well-developed scepticism about things, I'd recommend
> > ignoring the analytical pieces, analyzing the data
you
> > find yourself, and reporting back here.

I confess that when I wrote the above paragraph I was pretty sure my site would pop up but I didn't
know it would pop up in first place. Anyway, if you're not into googling, it's:
http://mywebpage.netscape.com/rechung/wattage

Since you're focusing on hillclimbs, note that in addition to the San Bruno Hillclimb data there's
also the Jiminy Peak road race and a pointer to Dede Demet-Barry's World Cup win. She had to climb
the same hill 13 times and I think you'd consider her properly "incentivized." Brrrr.

 

[Terry Morse]

The Pomeranian wrote:

> Terry Morse wrote:
> >
> > I've done some informal hill climbing experiments, where I rode up a 7% grade in different gears
> > while maintaining a heart rate of 160-165. At 50, 60, and 75-80 rpm, my speed was essentially
> > the same. The gearing made no difference at all.
>
> I have some questions:
>
> 1. What actual gearing did you have on your bike

13-26 8-speed cassette, 52/42 chainwheel

> 2. What was the road/route specifically

Old La Honda Road (East)

> 3. What is your max heart rate

About 180.
--
terry morse Palo Alto, CA http://www.terrymorse.com/bike/

 

[The Pomeranian]

Robert Chung wrote:
>
> "The Pomeranian" wrote:
> > Since he couldn't put out enough power at 105 rpm, and had a fixed gear, his only possiblity was
> > to slow down. That isn't explicitly necessary for multi speeds, where you can change the gear.
>
> Right, and that's one of the reasons why looking at the hour-record cadences is a dead-end despite
> what you wrote a few messages upthread.

It might be a dead end only to the extent that the athletes and trainers thought available power
really was unrelated to cadence -- after all, they know how fast they have to go and they get to
pick the gear. But with the commonality of cadence across riders and a century, that would make that
seem unprobable and eerie.

> > This specific purpose would be to find out how to obtain the highest average power possible for
> > the course, with the independent variable being cadence.
>
> Hmmm. Have you had any experience designing experiments and testing hypotheses?

Pretty much everyday.

> BTW, for the experiment as you've described it, you don't need a power meter. All you need is a
> cyclecomputer with a cadence sensor and a stopwatch.

Yes, this is _exactly_ why I defined the test this way -- no expensive power meter needed (maybe
prices will come down). I was trying to say that before: "The time and the constant climb and
equipment amount to a comparative power meter."

> Anyway, I would think that a flaw of this particular experiment is that if you don't find an
> effect (or you find a confusing effect like two peaks) you wouldn't know if you simply weren't
> accurate enough to detect the effect or if you were actually disproving your hypothesis.

Some uncertainty will remain regardless of the test. That is why a high degree of control is nice.
There is no way to do a double blind test. The subject can tell at least in part how fast they are
pedaling and how hard they are going. I don't know exactly what you are referring to when you
mention accuracy -- the sample size needs to be statistically significant. Gearing resolution from
to 6% to 8% is easily available. Perhaps you are concerned that a two-peak response could be
obscured if it was a function of grade and the grade on the test climb varied a good deal. Of
course, that is a different but related issue we've discussed before. If there is a high concern
about this, then they must be separated as independent variables -- the test climb must be graded
fairly constant. It is another dimension, another I'm not sure exists, but I can be open to it.

I also have to be open to "no effect." No effect *may* be saying that power versus rpm is flat and
that the Flat Power Cult were right all along. My purpose would not be to prove what I suspect. My
purpose would be to find the truth. In fact, a finding like "flat power" would end up making things
easier because at that point I could fogettaboutit. I don't think I would have a problem with two
peaks (or more!). If you look at my language you'll see I did not presume a single peak, however
flat any peak was.

> I've already tipped my hand that I think your hypothesis is ill-formed which is why I think you'll
> have difficulty coming to conclusions. But go ahead, have at it.

As a practical matter, I probably never will do that particular test. Almost any meaningful testing
will be tedious and would need to be done with statistical significance. I am a 46 yo bike rider
sometimes racer. I think I would find that taking training to this degree in my spare time would
take the fun out of riding. If I was involved in cycling professionally it would a different matter.
So you are 100% correct that I will have difficulty coming to high confidence conclusions by myself
and for myself. It would help a lot if the price for power meters fell.

> In the meantime, since you've said that you know how to analyze data (which makes your reticence
> to look at any even more puzzling) I'd suggest again that you and Terry and Frank, if they're
> still reading this thread, look at the data that are already available.

I'm not reticent. Recall I've looked at some of your's already and gave you my take with no
reservation. In short, the data I'm going to look at must come to me at a very low opportunity
cost. For me as an old nobody amateur just trying to mostly have fun, that means mostly doing hard
lunch time rides and suffering the variables and trying to make decent honest guesses to the best
of my ability.

> I confess that when I wrote the above paragraph I was pretty sure my site would pop up but I
> didn't know it would pop up in first place. Anyway, if you're not into googling, it's:
> http://mywebpage.netscape.com/rechung/wattage

I'll look at it more closely when I get a few minutes. Thanks.

> Since you're focusing on hillclimbs, note that in addition to the San Bruno Hillclimb data there's
> also the Jiminy Peak road race and a pointer to Dede Demet-Barry's World Cup win. She had to climb
> the same hill 13 times and I think you'd consider her properly "incentivized." Brrrr.

 

[The Pomeranian]

Terry Morse wrote:
>
> The Pomeranian wrote:
>
> > Terry Morse wrote:
> > >
> > > I've done some informal hill climbing experiments, where I rode up a 7% grade in different
> > > gears while maintaining a heart rate of 160-165. At 50, 60, and 75-80 rpm, my speed was
> > > essentially the same. The gearing made no difference at all.
> >
> > I have some questions:
> >
> > 1. What actual gearing did you have on your bike
>
> 13-26 8-speed cassette, 52/42 chainwheel
>
> > 2. What was the road/route specifically
>
> Old La Honda Road (East)
>
> > 3. What is your max heart rate
>
> About 180.

My max is now down to about 181. When in race condition and during rides where I think I'm doing
well I can ride up in the 170s for periods longer than 15 min. So I think you may not have been
going hard enough to reveal small differences (if they exist), although I'll leave the final
judgement of that up to you. For the purpose of maximum speed, I still wonder if I should pedal
faster than 80 when going uphill. I don't know. Traditionally I haven't had gears low enough to even
test that on many climbs -- I've been changing my equipment so I can actually try pedaling faster. I
crashed hard just before the Mt Tam HC this year, and so never went.

 

[Robert Chung]

"The Pomeranian" wrote:
>
> Robert Chung wrote:
> >
> > "The Pomeranian" wrote:
>
> > > This specific purpose would be to find out how to obtain the highest average power possible
> > > for the course, with the independent variable being cadence.
> >
> > Hmmm. Have you had any experience designing experiments and testing hypotheses?
>
> Pretty much everyday.

Excellent. Then you know that misspecifying your model and your hypothesis means that your tests are
going to be wrong. As you've undoubtedly guessed, I think you've misspecified your model and the
experiment you've proposed doesn't include an essential thing. I know this sounds cryptic but some
people like to figure things out by themselves and you strike me as that kind of person. Do you want
to figure it out, or do you want me to tell you? I'm not trying to play games, I'm just trying to be
helpful, so if you ordinarily like to figure things out but you simply don't have the time to do so
I'll be happy [eager] to tell you.

> As a practical matter, I probably never will do that particular test. Almost any meaningful
> testing will be tedious and would need to be done with statistical significance.

This is why I suggested honing your model and hypothesis. If you do it right, the testing would be
much (much much much) less tedious.

> In short, the data I'm going to look at must come to me at a very low opportunity cost.

Can't get much lower than http://mywebpage.netscape.com/rechung/wattage

 

[Terry Morse]

The Pomeranian wrote:

> My max is now down to about 181. When in race condition and during rides where I think I'm doing
> well I can ride up in the 170s for periods longer than 15 min. So I think you may not have been
> going hard enough to reveal small differences (if they exist), although I'll leave the final
> judgement of that up to you.

I can't maintain 170+ for more than about five minutes on a climb. If I do, my legs turn to jello,
and I'm forced to drop. 170 would be too high for me to do a test. It would wipe me out. I don't
race, so I don't have the motivation to find out.

> For the purpose of maximum speed, I still wonder if I should pedal faster than 80 when
> going uphill. I don't know. Traditionally I haven't had gears low enough to even test that
> on many climbs.

You probably could test some higher cadences on a 5% grade. Sand Hill Road in Menlo Park, west of
I-280 has a long enough section to do some cadence testing. Maybe I'll give that a try after I've
been back on the bike a few weeks. Four more week to go (a watched calendar never changes).
--
terry morse Palo Alto, CA http://www.terrymorse.com/bike/

 

[The Pomeranian]

Robert Chung wrote:
>
> "The Pomeranian" wrote:
> >
> > Robert Chung wrote:
> > >
> > > "The Pomeranian" wrote:
> >
> > > > This specific purpose would be to find out how to obtain the highest average power possible
> > > > for the course, with the independent variable being cadence.
> > >
> > > Hmmm. Have you had any experience designing experiments and testing hypotheses?
> >
> > Pretty much everyday.
>
> Excellent. Then you know that misspecifying your model and your hypothesis means that your tests
> are going to be wrong. As you've undoubtedly guessed, I think you've misspecified your model and
> the experiment you've proposed doesn't include an essential thing. I know this sounds cryptic but
> some people like to figure things out by themselves and you strike me as that kind of person.
>
> Do you want to figure it out, or do you want me to tell you? I'm not trying to play games, I'm
> just trying to be helpful, so if you ordinarily like to figure things out but you simply don't
> have the time to do so I'll be happy [eager] to tell you.

I'm a fan of free speech for at least as much practical reasons as for ideological reasons. That
means I think more voices can approach a better solution sooner, if everyone is willing to listen
and have their own thoughts/suppositions either included and refined or rejected.

So my little circumlocution means: yes, save me some work in both thinking and testing and tell me
straight out.

> > As a practical matter, I probably never will do that particular test. Almost any meaningful
> > testing will be tedious and would need to be done with statistical significance.
>
> This is why I suggested honing your model and hypothesis. If you do it right, the testing would be
> much (much much much) less tedious.
>
> > In short, the data I'm going to look at must come to me at a very low opportunity cost.
>
> Can't get much lower than http://mywebpage.netscape.com/rechung/wattage

I get gateway errors on some of the links. Also, I promise to stop writing "unprobable."

 

[The Pomeranian]

Tom Nakashima wrote:

> I can't help but think of the 1986 Tour de France, when LeMond & Hinault were hitting speeds of
> 60+ mph on the slopes of the Pyrenees. Viewing the tape, they were at times pedaling in unison on
> the straights and relaxing in the turns, pure poetry in motion.

They probably didn't have 53x12 gears and probably had 53x13 high gears.

To pedal 60 mph w/ a 53x13 means 187 rpm.

>> cad = mph2cad(26.5,53,13,50)
cad =
155. 5628
>> cad = mph2cad(26.5,53,13,60)
cad =
156. 6753
>> cad = mph2cad(26.5,53,12,50)
cad =
157. 5964
>> cad = mph2cad(26.5,53,12,60)
cad =
158. 3157

Even 50 mph w/ a 53x12 means 144 rpm. Nobody can sustain that cadence for long. I've hit 60 mph only
once in 26 years of "serious" cycling. That was at the Ted Smith RR near Buffalo, NY (in the hills
of the Boston Township). I've hit 55mph exactly once -- descending Tioga Pass towards Lee Vining
(with probably a 20+ mph tailwind). I could probably count all the times I went over 50 mph on my
fingers and toes.

50 mph just doesn't happen very often unless you happen to live close to one of the rare roads (and
conditions) that allows it. If Lemond and Hinault were going 50+ mph, they probably weren't
pedaling. For NorCal, the Patterson Pass descent is often about 50 mph because of the fairly
reliable howling tailwind and "open road."

 

[Robert Chung]

"The Pomeranian" wrote:

> > > In short, the data I'm going to look at must come to me at a very low opportunity cost.
> >
> > Can't get much lower than http://mywebpage.netscape.com/rechung/wattage
>
> I get gateway errors on some of the links.

Hmmm. The site is one of those maddening free things that is seriously underpowered. At some point
I'll have to move it somewhere else. Grumble.

Anyway, we know by definition that power is pedal force times pedal speed (or equivalently, torque
at the pedal times angular velocity of the pedal). That means that looking only at the relationship
between power and cadence is sort of like looking at the relationship between the area of a
rectangle and its height. There's an exact relationship (ignoring measurement error) between height,
length, and the area of the rectangle but if you only look at its height and its area, you can run
all the regressions you want but they won't reveal the true relationship because your model is
misspecified.

In the case of power, there may very well be a spot where it just so happens that for the data you
have at hand, a smoothed version of the curve relating power to cadence is going to have a localized
maximum. However, just as above, we know that this particular model is misspecified.

That's the theoretical stuff. As an empirical observation, power turns out to be more sensitive to
small changes in pedal force or torque than in pedal speed or cadence. You can see that if you
examine any of the data files at that site, but if you don't want to examine them yourself you can
look at the plots at the topic labelled, "Components of power" and either take my word for it that
the other data files look similar or check a couple of them at random.

From my perspective, though perhaps not from yours, there are two take-away messages: first, the
cadence-power curve isn't flat, but it's not particularly important that its not flat because you
can't change cadence at constant power without also changing pedal torque. They're intertwined, and
that's why simply looking at the cadence for the hour record attempts also only tells part of the
story -- the other part of the story is what were the torques or the wattages being produced. Since
no one recorded those data, it's hard to evaluate the cadences in isolation. In fact, I think it's
often more useful to think of cadence as a dependent variable rather than an independent one.

Second, and paradoxically, the near-flatness of the cadence curve doesn't say that a rider should be
indifferent to a particular gear. This is where I think Terry and Frank went wrong. After all, the
rider has got to produce the torque necessary to move the bike, so the rider may very well choose a
gear based not on cadence, but on the torque he's comfortably able to produce.

This is why I was saying that I thought you were right about gears, but for the wrong reason. I
don't think it has as much to do with a "preferred" cadence as you thought. I think it has to do
with the torque.

 

[Jay Beattie]

"The Pomeranian" <[email protected]> wrote in message
news:[email protected]...
>
>
> Tom Nakashima wrote:
>
> > I can't help but think of the 1986 Tour de France, when LeMond &
Hinault
> > were hitting speeds of 60+ mph on the slopes of the Pyrenees.
Viewing the
> > tape, they were at times pedaling in unison on the straights and
relaxing in
> > the turns, pure poetry in motion.
>
> They probably didn't have 53x12 gears and probably had 53x13 high
gears.
>
> To pedal 60 mph w/ a 53x13 means 187 rpm.
>
> >> cad = mph2cad(26.5,53,13,50)
> cad =
>155. 5628
> >> cad = mph2cad(26.5,53,13,60)
> cad =
>186. 6753
> >> cad = mph2cad(26.5,53,12,50)
> cad =
>143. 5964
> >> cad = mph2cad(26.5,53,12,60)
> cad =
>172. 3157
>
> Even 50 mph w/ a 53x12 means 144 rpm. Nobody can sustain that cadence for long. I've hit 60 mph
> only once in 26 years of "serious" cycling. That was at the Ted Smith RR near Buffalo, NY (in the
> hills of the Boston Township). I've hit 55mph exactly once -- descending Tioga
Pass
> towards Lee Vining (with probably a 20+ mph tailwind). I could
probably
> count all the times I went over 50 mph on my fingers and toes.
>
> 50 mph just doesn't happen very often unless you happen to live close
to
> one of the rare roads (and conditions) that allows it. If Lemond and Hinault were going 50+ mph,
> they probably weren't pedaling. For
NorCal,
> the Patterson Pass descent is often about 50 mph because of the fairly reliable howling tailwind
> and "open road."

There are plenty of places to hit 50 or 60mph in the Sierra and elsewhere -- even in my 'hood up
here in the Cascades. The deal is that you are not going to be pedaling down any of them. Flailing
your legs at 170 rpms is the last thing you want to do while flying down hill at 60mph in a full
tuck -- when you feel like every little rock or rut is going to send you airborne. Even if you could
spin like a bobbin at 170 rpms, the resulting air flow disturbance would probably slow you down.
(Sorry, folks, no wind-tunnel data sets for that assertion). -- Jay Beattie.

 

[Terry Morse]

Robert Chung wrote:

> Second, and paradoxically, the near-flatness of the cadence curve doesn't say that a rider should
> be indifferent to a particular gear. This is where I think Terry and Frank went wrong. After all,
> the rider has got to produce the torque necessary to move the bike, so the rider may very well
> choose a gear based not on cadence, but on the torque he's comfortably able to produce.

I made this same point earlier, (renamed "Preferred Cadence"):

"So if aerobic efficency is the only goal, always pedaling at one's preferred cadence is a poor
strategy. Preventing muscle fatigue is another important issue, however. For that, I suggest the
most important factor is maintaining peak pedal forces below a threshold that would cause fatigue.
Having a low enough gear to stay at or below this pedal force would then be the goal of gear
selection. This is a different criteria than simply choosing enough gears to be able to pedal at
one's preferred cadence at any speed."

ref: http://makeashorterlink.com/?B32A12853

--
terry morse Palo Alto, CA http://www.terrymorse.com/bike/