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Main
Date: 31 May 2007 18:57:48
From: Dan Connelly
Subject: Simoni power estimation
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According to www.cyclingnews.com/news.php?id=news/2007/may07/may31news2 :
Gilberto Simoni (Saunier Duval-Prodir) conquered the 10.1-kilometre Monte Zoncolan in 1850 metres per hour according to La Gazzetta dello Sport. The speed, 39 minutes over the 1203 metres, 1850 VAM (Velocity Ascended, Metres per hour Vm/h), was faster than that of Ivan Basso on the Maielletta Passo Lanciano in 2006, 1805 VAM. Marco Pantani blasted up the Alpe d'Huez with a 1791 VAM and Danilo Di Luca did the final four kilometres of Tre Cime di Lavaredo with a 1750 VAM.
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The steep climb reduces the influence of rolling resistance and wind resistance. Rolling resistance losses were further reduced by the fresh pavement.
Profile of the climb:
http://www.cyclingnews.com/road/2007/giro07/graphics/profile17a.gif
vertical gain: 1200 meters
effective climbing from rolling resistance (assume Crr = 0.5%) : 10.1 km * 0.005 = 50.5 meters
net effective climbing rate = (1200 + 50.5) / 1200 * 1850 = 1928 m/hr
Assume CdA =~ 0.3 m^2
speed = 10.1 km * 1850 m/hr / 1200 m / 3.6 (m/s / km/hr) = 4.32 m/sec
Assume rho = 1.2 kg / m^3
wind power = 4.32^3 * 1.2 * 0.3 / 2 = 14.6 watts (slightly less from drafting, slightly more from nonuniform speed).
climbing + RR power = 1928 m/hr / 3600 s/hr * 9.8 m / s^2 = 5.25 W/kg (total weight)
Assume bike + stuff = 9 kg
body = 60 kg
power/body mass = 5.25 W/kg * (69 / 60) + 14.5 W / 60 kg = 6.28 W/kg for 0.65 hours.
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So, for Old La Honda (393 meters, 7.3%, Woodside, CA), assuming Crr = 0.6%, assuming a critical power model with AWC/CP = 60 seconds:
OLH time = 13.88 minutes (6.56 W/kg)
(I solved this iteratively)
These numbers are not at the level of the great Alpe d'Huez climbs. But we knew that already about Simoni...
Dan
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Date: 02 Jun 2007 17:16:58
From: Phil Holman
Subject: Re: Simoni power estimation
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"Dan Connelly" <d_j_c_o_n_n_e_l@y_a_h_o_o_._c_o_m > wrote in message
news:MUE7i.10458$2v1.7847@newssvr14.news.prodigy.net...
> According to
> www.cyclingnews.com/news.php?id=news/2007/may07/may31news2 :
>
> Gilberto Simoni (Saunier Duval-Prodir) conquered the 10.1-kilometre
> Monte Zoncolan in 1850 metres per hour according to La Gazzetta dello
> Sport. The speed, 39 minutes over the 1203 metres, 1850 VAM (Velocity
> Ascended, Metres per hour Vm/h), was faster than that of Ivan Basso on
> the Maielletta Passo Lanciano in 2006, 1805 VAM. Marco Pantani blasted
> up the Alpe d'Huez with a 1791 VAM and Danilo Di Luca did the final
> four kilometres of Tre Cime di Lavaredo with a 1750 VAM.
>
> -----
>
> The steep climb reduces the influence of rolling resistance and wind
> resistance. Rolling resistance losses were further reduced by the
> fresh pavement.
>
> Profile of the climb:
> http://www.cyclingnews.com/road/2007/giro07/graphics/profile17a.gif
>
> vertical gain: 1200 meters
> effective climbing from rolling resistance (assume Crr = 0.5%) : 10.1
> km * 0.005 = 50.5 meters
> net effective climbing rate = (1200 + 50.5) / 1200 * 1850 = 1928 m/hr
>
> Assume CdA =~ 0.3 m^2
> speed = 10.1 km * 1850 m/hr / 1200 m / 3.6 (m/s / km/hr) = 4.32 m/sec
> Assume rho = 1.2 kg / m^3
> wind power = 4.32^3 * 1.2 * 0.3 / 2 = 14.6 watts (slightly less from
> drafting, slightly more from nonuniform speed).
>
> climbing + RR power = 1928 m/hr / 3600 s/hr * 9.8 m / s^2 = 5.25 W/kg
> (total weight)
>
> Assume bike + stuff = 9 kg
> body = 60 kg
>
> power/body mass = 5.25 W/kg * (69 / 60) + 14.5 W / 60 kg = 6.28 W/kg
> for 0.65 hours.
>
>
> --------------
> So, for Old La Honda (393 meters, 7.3%, Woodside, CA), assuming Crr =
> 0.6%, assuming a critical power model with AWC/CP = 60 seconds:
>
> OLH time = 13.88 minutes (6.56 W/kg)
>
> (I solved this iteratively)
>
> These numbers are not at the level of the great Alpe d'Huez climbs.
> But we knew that already about Simoni...
>
> Dan
>
Andy Coggan's data for power to weight ratio are:
Time
1 min 5 min 20 min
World Champ 11.50 7.60 6.62
World Class 10.90 7.06 6.14
It interpolates to a world class performance.
Phil H
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Date: 03 Jun 2007 03:44:30
From: Dan Connelly
Subject: Re: Simoni power estimation
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Phil Holman wrote:
> "Dan Connelly" <d_j_c_o_n_n_e_l@y_a_h_o_o_._c_o_m> wrote in message
>> power/body mass = 5.25 W/kg * (69 / 60) + 14.5 W / 60 kg = 6.28 W/kg
>> for 0.65 hours.
>>
In another forum, it was pointed out I overestimated wind resistance, due to the climb being a significant altitude. This would reduce the power to 6.26 W/kg. OTOH, I only guessed at CdA, using 0.3 m^2, and at Crr, using 0.5%.
>
> Andy Coggan's data for power to weight ratio are:
> Time
> 1 min 5 min 20 min
> World Champ 11.50 7.60 6.62
> World Class 10.90 7.06 6.14
>
> It interpolates to a world class performance.
Interesting. But then, that only puts Simoni in Bettini's class as a climber on 20-minute hills :).
Dan
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Date: 03 Jun 2007 09:52:51
From: RonSonic
Subject: Re: Simoni power estimation
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On Sun, 03 Jun 2007 03:44:30 GMT, Dan Connelly
<d_j_c_o_n_n_e_l@y_a_h_o_o_._c_o_m > wrote:
>Phil Holman wrote:
>> "Dan Connelly" <d_j_c_o_n_n_e_l@y_a_h_o_o_._c_o_m> wrote in message
>
>>> power/body mass = 5.25 W/kg * (69 / 60) + 14.5 W / 60 kg = 6.28 W/kg
>>> for 0.65 hours.
>>>
>
>In another forum, it was pointed out I overestimated wind resistance, due to the climb being a significant altitude. This would reduce the power to 6.26 W/kg. OTOH, I only guessed at CdA, using 0.3 m^2, and at Crr, using 0.5%.
>
>
>>
>> Andy Coggan's data for power to weight ratio are:
>> Time
>> 1 min 5 min 20 min
>> World Champ 11.50 7.60 6.62
>> World Class 10.90 7.06 6.14
>>
>> It interpolates to a world class performance.
>
>Interesting. But then, that only puts Simoni in Bettini's class as a climber on 20-minute hills :).
Which might be perfectly fair, but what happens on a 40 minute hill? That's
where real climbers distinguis themselves. It's kinda hard to think of a 20
minute hill as a "sprinters climb" but by comparison.
Just more proof of what a badass the cricket is.
Ron
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Date: 03 Jun 2007 21:35:20
From: Dan Connelly
Subject: Re: Simoni power estimation
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RonSonic wrote:
> On Sun, 03 Jun 2007 03:44:30 GMT, Dan Connelly
> <d_j_c_o_n_n_e_l@y_a_h_o_o_._c_o_m> wrote:
>
>> Phil Holman wrote:
>>> "Dan Connelly" <d_j_c_o_n_n_e_l@y_a_h_o_o_._c_o_m> wrote in message
>>>> power/body mass = 5.25 W/kg * (69 / 60) + 14.5 W / 60 kg = 6.28 W/kg
>>>> for 0.65 hours.
>>>>
>> In another forum, it was pointed out I overestimated wind resistance, due to the climb being a significant altitude. This would reduce the power to 6.26 W/kg. OTOH, I only guessed at CdA, using 0.3 m^2, and at Crr, using 0.5%.
>>
>>
>>> Andy Coggan's data for power to weight ratio are:
>>> Time
>>> 1 min 5 min 20 min
>>> World Champ 11.50 7.60 6.62
>>> World Class 10.90 7.06 6.14
>>>
>>> It interpolates to a world class performance.
>> Interesting. But then, that only puts Simoni in Bettini's class as a climber on 20-minute hills :).
>
> Which might be perfectly fair, but what happens on a 40 minute hill? That's
> where real climbers distinguis themselves. It's kinda hard to think of a 20
> minute hill as a "sprinters climb" but by comparison.
>
> Just more proof of what a badass the cricket is.
>
> Ron
Bettini probably has an AWC/CP more than the 60 seconds I assumed for Pantani and Simoni, so is probably able to produce a relatively larger increase in power at shorter durations.
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Date: 03 Jun 2007 05:34:47
From: Dan Connelly
Subject: Re: Simoni power estimation
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Dan Connelly wrote:
> Phil Holman wrote:
>> Andy Coggan's data for power to weight ratio are:
>> Time
>> 1 min 5 min 20 min
>> World Champ 11.50 7.60 6.62
>> World Class 10.90 7.06 6.14
>>
>> It interpolates to a world class performance.
>
> Interesting. But then, that only puts Simoni in Bettini's class as a
> climber on 20-minute hills :).
>
> Dan
One point of comparison: Andrew deals in "SRM power", while I tend to deal in "Powertap power", and the two differ by the drivetrain efficiency....
So an estimated 6.26 W/kg, assuming a drive train efficiency of 97%, becomes 6.45 W/kg up the Zoncolan. And the estimated power up OLH, 6.56 W/kg becomes 6.76 W/kg.
Dan
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Date: 01 Jun 2007 13:07:23
From: Keith
Subject: Re: Simoni power estimation
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>The steep climb reduces the influence of rolling resistance and wind resistance. Rolling resistance losses were further reduced by the fresh pavement.
Yes, that's what I thought when I read that snippet in CN, it seemed
like the guy was more interested in raising "questions" about the
performance than using common sense to analyze it.
The Angliru would be in the same case, except they always seem to
climb it in horrible weather and the pavement is crappy..
>So, for Old La Honda (393 meters, 7.3%, Woodside, CA), assuming Crr = 0.6%, assuming a critical power model with AWC/CP = 60 seconds:
>
>OLH time = 13.88 minutes (6.56 W/kg)
>
>(I solved this iteratively)
>
>These numbers are not at the level of the great Alpe d'Huez climbs. But we knew that already about Simoni...
Do you have a link where these Alpe d'Huez climbs have been anlayzed ?
>Dan
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Date: 02 Jun 2007 23:04:23
From: Dan Connelly
Subject: Re: Simoni power estimation
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Keith wrote:
>
> Do you have a link where these Alpe d'Huez climbs have been anlayzed ?
>
I analyzed it using the same method.
It's hard to find info on exactly where the climb was timed. I find 13.8 km, 14.0km, 14.5km. Assume the following:
L'Alpe d'Huez: 13.8 km @ 8.1% (1118 meters)
Marco Pantani's time = 37min 35 seconds
assume: mass = 55km, mass of other stuff = 6km, Crr = 0.5%, CdA = 0.3, rho = 1.1 kg/m^3.
Then Pantani's power on L'Alpe: 6.69 W/kg, or 6.90 W/kg assuming 97% drivetrain efficiency.
Assuming AWC/CP = 1 minute, with Crr=0.6%, rho=1.2%, for Old La Honda road: 13.41 minutes (7.22 W/kg @ 97%).
My time this Wednesday up the same climb: 18.43 minutes @ 272 watts (PowerTap), which fits the model quite nicely (within the uncertainty of my system mass). This is around 4.91 W/kg @ 97% drivetrain efficiency.... sigh.
Dan
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