Power Data Estimates for the climbing stages

[Escarabajo]

Tour de Suisse 2011, Stage 3, HC climb Grosse Scheidegg [last 13.0 Km]

Damiano Cunego

Elevation / Höhenmeter [m] : 981 m
Distance / Streckenlänge [Km] : 13.0 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 2344 = 39 min 4 sec = 39:04
Weight rider / Gewicht Fahrer [kg] : 58 kg [Source: TeamLampre.it]
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 7.5 %
Average speed / mittlere Geschwindigkeit : 19.9 Km/h
Total weight / Gesamtgewicht : 66.0 kg

Power : 330.9 Watt
Power / kg : 5.7 Watt / kg

Source: [ http://www.rst.mp-all.de/bergauf.htm ]

Thanks.

I thought numbers were going to be higher. This is almost an effort equivalent to Alpe de Huez. Although road conditions were slightly bad yesterday as compared to Alpe d'Huez. Maybe you should adjust a bit the rolling coefficient.

Maybe these guys need to up their game a bit if they want to be players in the Tour de France.

 

[Benotti69]

should riders be made to undergo a simple medical before a GT for e.g. determine weight. Do we believe the teams website about rider weights/heights? as weight is an important part of the calculation in power outputs.

 

[halamala]

I thought numbers were going to be higher. This is almost an effort equivalent to Alpe de Huez.

Yeah, I thought too. I calculated also Cunego's numbers from last 3.65 Km.

Tour de Suisse 2011, Stage 3, HC climb Grosse Scheidegg [last 3.65 Km]

Damiano Cunego

Elevation / Höhenmeter [m] : 337 m
Distance / Streckenlänge [Km] : 3.65 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 735 = 12 min 15 sec = 12:15
Weight rider / Gewicht Fahrer [kg] : 58 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 9.2 %
Average speed / mittlere Geschwindigkeit : 17.8 Km/h
Total weight / Gesamtgewicht : 66.0 kg

Power : 343.1 Watt
Power / kg : 5.9 Watt / kg

Source: [ http://www.rst.mp-all.de/bergauf.htm ]

It's still under 6.0 W/kg.

 

[roundabout]

should riders be made to undergo a simple medical before a GT for e.g. determine weight. Do we believe the teams website about rider weights/heights? as weight is an important part of the calculation in power outputs.

I thought that they did?

I remember the usual x is the lightest rider, y is the heaviest (and the tallest and the shortest etc) being announced just before or during the early stages of the Tour.

 

[Alex Simmons/RST]

should riders be made to undergo a simple medical before a GT for e.g. determine weight. Do we believe the teams website about rider weights/heights? as weight is an important part of the calculation in power outputs.

Well riders may well undergo medical and morphological checks but not for the purpose of satisfying people's curiosity on an internet forum.

 

[Ferminal]

Thanks for that halamala.

He looked amazing, so surprised to see him struggling to crack 6.

Not enough for the Tour at this stage

 

[Le breton]

should riders be made to undergo a simple medical before a GT for e.g. determine weight. Do we believe the teams website about rider weights/heights? as weight is an important part of the calculation in power outputs.

weight is an important part of the calculation in power outputs

Yes, of course, but let me repeat for the nth time that it practically drops out of the calculation when you consider watts/kg.

 

[danjo007]

im wondering how many "expert cyclists" here actually know what its like to ride at 6watts/kg?

 

[Le breton]

Thanks.

I thought numbers were going to be higher. This is almost an effort equivalent to Alpe de Huez. Although road conditions were slightly bad yesterday as compared to Alpe d'Huez. Maybe you should adjust a bit the rolling coefficient.

Maybe these guys need to up their game a bit if they want to be players in the Tour de France.

I only once rode my bike from Meirigen to Grosse Scheidegg. Beautiful ride through the Rosenlauital.
I remember a road with large variations in gradient, so that to get a reasonable estimate of power output it is necessary to segment the climb according to %age.

 

[Le breton]

Yeah, I thought too. I calculated also Cunego's numbers from last 3.65 Km.

[
Power : 343.1 Watt
Power / kg : 5.9 Watt / kg

Source: [ http://www.rst.mp-all.de/bergauf.htm ]

It's still under 6.0 W/kg.

Between 1597 and 1962 m elevation you can't really expect to produce as much power as, say, between 700 and 1065 m.

Add 0.2-0.3 watts/kg for comparison?

 

[python]

should riders be made to undergo a simple medical before a GT for e.g. determine weight. Do we believe the teams website about rider weights/heights? as weight is an important part of the calculation in power outputs.

good question and the controversy with armstrong's weight or wiggins' or whoever is the case in point.

weighing is mandatory before some races as part of medical checks. but of course some riders play (up or down) their true weight depending on the message they try to spin.

there is also the fact that riders weight is variable even during the races as they sweat.

overall, i consider rider weight as another factor to be considered with some tolerance, say, +/- 1kg from the historically listed value.

 

[Le breton]

Meiringen - Grosse Scheidegg

For memory sake I looked up the profile
http://www.salite.ch/grosse.asp?Mappa=http://map.search.ch/meiringen

As I recollected, there are big variations in %age

 

[Le breton]

It does not take much wind. For instance we would barely feel a wind of 0.5 - 1m/s, yet even that can have a sizeable impact on the power estimate.
.........

Since nobody answered your claim, I'll take a shot at it.

What is the impact of a 1 m/s wind on a good pro climber?
Let's say one able to produce 6 watts/kg.

I take 67 kg +8kg, hence producing 402 watts, with CdA = 0.375 m^2
At air density 1.1 g/cm^3

For a velocity of 6 m/s (21.6 km/h), he needs to produce
44.6 watts to fight air resistance.

Now, with a favourable wind, those 44.6 watts are reduced to 44.6 times (5.72/6)^2 = 40.6 watts. A 4 watts benefit, ie 1%.

At 21.6 km/h he needs to produce 398 watts (instead of 402),
i.e 5.94 watts/kg. That's equivalent to about 15 seconds difference on a steep (~8%) 30 mn climb.

If the wind "blows" against, he will have to produce 406 watts to stay at 21.6 km/h
i.e 6.06 watts/kg.

On the calculation, the effect of a 1 km/h breeze is roughly the same as that of a 0.8% mistake on the altitude difference ( 8 meters on a 1000 meters climb).

At 21.6 km/h it is also the same as a ~10% excursion of the air density, due either to altitude or temperature and less than the saving from drafting ( roughly 12 watts behind 1 racer, maybe 16 watts in the middle of a sizeable group)


.

 

[Escarabajo]

im wondering how many "expert cyclists" here actually know what its like to ride at 6watts/kg?

I am not an expert, but for me is an “impossibility”. I can not even smell it.

 

[Bavarianrider]

I am not an expert, but for me is an “impossibility”. I can not even smell it.

No problem,






for a minute

 

[dbrower]

im wondering how many "expert cyclists" here actually know what its like to ride at 6watts/kg?

Almost all of us can, but not for very long. I used to be able to do it for, oh, a minute. It's fun until about 5 seconds before complete failure. That's the hard part.

-dB

 

[Parrulo]

Almost all of us can, but not for very long. I used to be able to do it for, oh, a minute. It's fun until about 5 seconds before complete failure. That's the hard part.

-dB

i never measured my power on the bike. but on the gym a few weeks ago while doing some rowing(i think thats the name) my trainer told me to stay above 350 watts for the entire last minute of the training section and at first you feel good but its awfull when you want to keep up the power and give it all you have but all you see is the power meter showing how your watts decreased with time, even with all the effort you are putting in.

this is one of the reasons why i respect cyclists so much.

anyway sounds like nothing clinic related can be said about cunego. great ride by him

 

[danjo007]

Almost all of us can, but not for very long. I used to be able to do it for, oh, a minute. It's fun until about 5 seconds before complete failure. That's the hard part.

-dB

if you had access to the data being recorded, you'd actually know rather than just guessing.
and then sustain (an average) for between 12-30 minutes.

there's only going to be about a dozen people on this earth that is going to be able to do that - and none of them posting here.

 

[dbrower]

if you had access to the data being recorded, you'd actually know rather than just guessing.
and then sustain (an average) for between 12-30 minutes.

there's only going to be about a dozen people on this earth that is going to be able to do that - and none of them posting here.

I think your humor detector is a bit off. We were asked about people who could do 6 w/kg, not people who can do 6 w/kg for 12-30 minutes. Your substance was being agreed with, not disputed. It was the form of the question that was being skewered. I've got the data, and know very well how long I can hold 6 w/kg, and it isn't pretty.

 

[Alex Simmons/RST]

Since nobody answered your claim, I'll take a shot at it.

I think your calcs are out.

Taking 65kg rider (8kg bike) capable of 400W for around 30-min. I suggest a CdA a bit less than yours, say 0.32m^2 *, Crr 0.005.

Now if we have an 8% gradient with zero wind, 400W delivers a speed of 21.6 km/h.

If we account for wind ranging from a 1m/s tailwind to a 1m/s headwind, the power estimates for same climbing speed range from 388W to 413W (-3.0% to +3.3%).

Remember that a 1m/s wind is barely perceptible.

A 2m/s tail/head wind range would see power for same speed range from 380W to 429W (-5.0% to +7.3%).

Refer to the chart I posted in previous blog link about power estimates up Alpe d'Huez and impact of wind on estimates.

* not that it matters - higher CdA would just increase the power range estimate further

 

[Ferminal]

if you had access to the data being recorded, you'd actually know rather than just guessing.
and then sustain (an average) for between 12-30 minutes.

there's only going to be about a dozen people on this earth that is going to be able to do that - and none of them posting here.

I'd hope they aren't wasting their time posting here when they can be out making a living off it.

 

[laziali]

there's only going to be about a dozen people on this earth that is going to be able to do that - and none of them posting here.

you would be surprised, my friend

 

[Le breton]

I think your calcs are out.

Taking 65kg rider (8kg bike) capable of 400W for around 30-min. I suggest a CdA a bit less than yours, say 0.32m^2 *, Crr 0.005.

Now if we have an 8% gradient with zero wind, 400W delivers a speed of 21.6 km/h.

If we account for wind ranging from a 1m/s tailwind to a 1m/s headwind, the power estimates for same climbing speed range from 388W to 413W (-3.0% to +3.3%).

Remember that a 1m/s wind is barely perceptible.

A 2m/s tail/head wind range would see power for same speed range from 380W to 429W (-5.0% to +7.3%).

Refer to the chart I posted in previous blog link about power estimates up Alpe d'Huez and impact of wind on estimates.

* not that it matters - higher CdA would just increase the power range estimate further

Thanks Alex, I wrote 1 m/s but meant 1 km/h and did the calculation for 1 km/h because I read your post too fast.

(which is a bit stupid as I chose 21.6 km/h to have exactly 6 m/s)

I rechecked everything before posting but not that


On the CdA, 0.32 is really VERY LOW FOR A 67 kg RACER IN CLIMBING POSITION.

For the Crr, I have measured it personnally on a 5km strech of road quite similar to many roads in France and obtained 0.0036. I am quite happy to use 0.004 as suggested by analyticcycling.com.

Here is what I meant to write. Very sorry for confusing the issue.

Since nobody answered your claim, I'll take a shot at it.

What is the impact of a 1 km/h(1 m/s) wind on a good pro climber?
Let's say one able to produce 6 watts/kg.

I take 67 kg +8kg, hence producing 402 watts, with CdA = 0.375 m^2
At air density 1.1 g/cm^3

For a velocity of 6 m/s (21.6 km/h), he needs to produce
44.6 watts to fight air resistance.

Now, with a favourable wind, those 44.6 watts are reduced to 44.6 times (5.72/6)^2 = 40.6 watts. A 4 watts benefit, ie 1%.

At 21.6 km/h he needs to produce 398 watts (instead of 402),
i.e 5.94 watts/kg. That's equivalent to about 15 seconds difference on a steep (~8%) 30 mn climb.

If the wind "blows" against, he will have to produce 406 watts to stay at 21.6 km/h
i.e 6.06 watts/kg.

On the calculation, the effect of a 1 km/h breeze is roughly the same as that of a 0.8% mistake on the altitude difference ( 8 meters on a 1000 meters climb).

At 21.6 km/h it is also the same as a ~10% excursion of the air density, due either to altitude or temperature and less than the saving from drafting ( roughly 12 watts behind 1 racer, maybe 16 watts in the middle of a sizeable group)

Size of effect for 3.6 km/h wind :

44.6 (7/6)^2 - 44.6 = 16 watts increase in wattage to keep 21.6 km/h (+4%)
44.6 (5/6)^2 -44.6 = - 13.6 watts reduction in wattage to stay at 21.6 km/h (-3.4%)

 

[halamala]

Kruijswijk climbed 6.0 W/kg

Preliminary calculation

Tour de Suisse 2011, Stage 6, HC climb Triesenberg/Malbun [12.8 Km]

Steven Kruijswijk

Elevation / Höhenmeter [m] : 1132 m
Distance / Streckenlänge [Km] : 12.8 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 2415 = 40 min 15 sec = 40:15
Weight rider / Gewicht Fahrer [kg] : 64 kg [Source: Rabobank.com]
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.8 %
Average speed / mittlere Geschwindigkeit : 19.0 Km/h
Total weight / Gesamtgewicht : 72.0 kg

Power : 386.5 Watt
Power / kg : 6.0 Watt / kg

Source: [ http://www.rst.mp-all.de/bergauf.htm ]

 

[roundabout]

Shame that the time schedule isn't particularly detailed as the data for the last 2 km would have also been interesting.

Considering that Krijswijk was pretty far back in the group for most of the climb even at 20 km/h his 'real' watts should be lower.