Power Data Estimates for the climbing stages

[mektronic]

No, they are not estimated based on ascent times. They are from their published SRM files. The only uncertainty is rider weight. Nibali's weight is listed either at 64 of 63 kg. At 63kg, his average on that last climb would be 5.7 watts/kg.

Exactly - "listed" weight, not actual calculated mass. You don't know how much he weighed, how much his clothes weighed, how many gels he had in his pockets, how much fluid in his bottles, the inflation pressure of his tyres etc.

All of these create uncertainties and errors in the determination of speed from purely w/kg.

 

[maxmartin]

Nibali maybe drafted more than Jani? Especially with the the less steep parts of La Toussuire it could have led to some difference...

Nibali is always smart!!!

 

[mastersracer]

Exactly - "listed" weight, not actual calculated mass. You don't know how much he weighed, how much his clothes weighed, how many gels he had in his pockets, how much fluid in his bottles, the inflation pressure of his tyres etc.

All of these create uncertainties and errors in the determination of speed from purely w/kg.

I'm unclear on your position. There's no need to determine speed from power. Without a power file, power has to be estimated from speed plus many assumptions (which have been thoroughly criticized before in this thread). But in these cases we have access directly to the power files and know, eg., Nibali averaged 360 watts on the final climb. Watts/kg are derived from rider mass, not total mass. There's some uncertainty about rider weight - but even a kg +/- only results in a difference of about .1 watt/kg.

The fact that 2 riders produced approximately the same watts/kg but produced different times isn't relevant to the issue (we know this to be true especially in time trials due to differences in aerodynamics). Can't tell if you are agreeing with this or are saying something against it.

 

[zlev11]

Nibali maybe drafted more than Jani? Especially with the the less steep parts of La Toussuire it could have led to some difference...

for whatever it's worth, Brajkovic attacked first, then was joined by VDB and Pinot. then Nibali attacked, was caught by the Wiggins group, attacked again and joined the three up the road, and stayed with them to the finish. Jani was dropped by Froome's acceleration and came in a minute back by himself. so Brajkovic was definitely by himself for longer.

 

[halamala]

Has anybody compared the times on La Toussuire to those in 2006? That was a different stage, with the final climb ridden more agressively, but it would be an interesting comparison.

2006 Carlos Sastre ~44:45.
2012 Chris Froome, Thibaut Pinot ~44:55

 

[mektronic]

The fact that 2 riders produced approximately the same watts/kg but produced different times isn't relevant to the issue (we know this to be true especially in time trials due to differences in aerodynamics). Can't tell if you are agreeing with this or are saying something against it.

I'm agreeing with this bit. But pointing out that when people attempt to back calculate (not in the case of Nibali/Brajkovic) then the numbers are often out and it's relatively futile.

On the listed weight issue, remember that people are quibbling over 0.1w/kg here!

 

[jens_attacks]

Has anybody compared the times on La Toussuire to those in 2006? That was a different stage, with the final climb ridden more agressively, but it would be an interesting comparison.

.................

 

[D-Queued]

2006 Carlos Sastre ~44:45.
2012 Chris Froome, Thibaut Pinot ~44:55

That clinches it.

I am dropping my suspicions of Froome.

Dave.

 

[Ferminal]

Col de la Madeleine
2012:25,3 km@6,2%---1:05:17---average speed 23.25 km/h(P.Velits-Kessiakoff)
2010:25,3 km@6,2%---1:04:59---average speed 23.36 km/h(A.Schleck-Contador)

Thought those two were going fast.

 

[Unkown]

Thought those two were going fast.

Andy and Alberto were stopping and starting on that climb though, not riding flat out the whole way up it, but still thats a fast climb by Velits and Kessiakoff.

 

[Lanark]

Andy and Alberto were stopping and starting on that climb though, not riding flat out the whole way up it, but still thats a fast climb by Velits and Kessiakoff.

Barely though, their teams did a fine job setting a high pace, and Schleck and Contador had a very steady pace in the last 8 km (increasing the gap to the competition).

At least this settles the 'the numbers are so low the Sky-boys must be clean' argument. Froome was almost as fast as the best in 2006, and if he tried he certainly could have beat that time. A year we know the peloton was still doped to the gills. Just to be sure though, a walking stick doesn't have gills right?

 

[_frost]

...But in these cases we have access directly to the power files and know, eg., Nibali averaged 360 watts on the final climb. Watts/kg are derived from rider mass, not total mass. There's some uncertainty about rider weight - but even a kg +/- only results in a difference of about .1 watt/kg...

There might several other reasons for difference in speed but one thing to note is that powermeters require calibration, zeroing and are affected by eg. oval chainrings (depending on used technology). You cannot 100% count even on published powerfiles.

 

[jordan5000]

Anybody got numbers for today?

 

[nogav1ca]

vetooo ‏@ammattipyoraily
Col de Peyresourde (9.5 km, 6.9 %, 657 m). Nibali, Wiggins, Froome: 24 min 28 sec, 23.30 Kph, VAM 1612 m/h, 5.99 W/kg. #tdf #tdf12
Retweeted by Jonathan Vaughters

I'd say it's a bit less than 5,99 W/kg, as there was tailwind.

 

[MacRoadie]

Check:

http://www.sportsscientists.com/

Their twitter feed has lots of daily power numbers.

Col de Peyresourde (9.5 km,6.9 %,657 m). Nibali,Wiggins, Froome: 24:28, VAM 1612 m/h, 5.99 W/kg

 

[Bala Verde]

bump
......

 

[claveyrolat]

http://www.rue89.com/rue89-sport/20...meilleur-grimpeur-pinot-super-regulier-233861

Very interesting article from Fred Portoleau, with many figures put into perspective.

 

[BroDeal]

Was this Q&A ever posted.

http://www.ridemedia.com.au/?p=6440

Can you talk, for example, about the day to Morzine in the Dauphiné? It was billed as what could have been an absolutely fantastic stage but really you guys tapped out such a tempo that it killed off any chance of attacks. There were some guys who were only just able to hold on while going up the climb… but at the top Cadel went on the attack. What do you make of that tactic?
...
Did you have your SRM on the bike that day?

Michael Rogers: “Yeah.”

Going up the climb, what sort of power were you generating?

Michael Rogers: “We did [the Joux Plane climb] in 34:50, I think, and I averaged 440 Watts. That was one of my highest every power reports.”

---
Also

Michael Rogers: “I’ve seen a five to seven per cent increase in my general threshold power.

 

[Tyler'sTwin]

Was this Q&A ever posted.

http://www.ridemedia.com.au/?p=6440

Can you talk, for example, about the day to Morzine in the Dauphiné? It was billed as what could have been an absolutely fantastic stage but really you guys tapped out such a tempo that it killed off any chance of attacks. There were some guys who were only just able to hold on while going up the climb… but at the top Cadel went on the attack. What do you make of that tactic?
...
Did you have your SRM on the bike that day?

Michael Rogers: “Yeah.”

Going up the climb, what sort of power were you generating?

Michael Rogers: “We did [the Joux Plane climb] in 34:50, I think, and I averaged 440 Watts. That was one of my highest every power reports.”

---
Also

Michael Rogers: “I’ve seen a five to seven per cent increase in my general threshold power.

He might as well admit to doping, because no one can be stupid enough to think he's matching his Ferrari & Freiburg numbers at age 32 and clean as a whistle.

 

[Ripper]

He might as well admit to doping, because no one can be stupid enough to think he's matching his Ferrari & Freiburg numbers at age 32 and clean as a whistle.

Well, it is possible, or perhaps he is comparing to his non-doped numbers.


BTW, my toots smell like lavender and I believe in unicorns.

 

[Ripper]

Honest question - w/kg is based on rider weight only, correct? It is not total mass?

 

[Parrulo]

Honest question - w/kg is based on rider weight only, correct? It is not total mass?

total weight of rider+equipment( bike)

 

[Race Radio]

Was this Q&A ever posted.

http://www.ridemedia.com.au/?p=6440

Can you talk, for example, about the day to Morzine in the Dauphiné? It was billed as what could have been an absolutely fantastic stage but really you guys tapped out such a tempo that it killed off any chance of attacks. There were some guys who were only just able to hold on while going up the climb… but at the top Cadel went on the attack. What do you make of that tactic?
...
Did you have your SRM on the bike that day?

Michael Rogers: “Yeah.”

Going up the climb, what sort of power were you generating?

Michael Rogers: “We did [the Joux Plane climb] in 34:50, I think, and I averaged 440 Watts. That was one of my highest every power reports.”

---
Also

Michael Rogers: “I’ve seen a five to seven per cent increase in my general threshold power.

There is no way those number are correct. that would be about 6.7 w/kg for 34 min. No way they were going that fast.

 

[Ferminal]

Yeh, Porte was estimated @ 6.0W/kg.

Which would still be career best for Rogers.

 

[BroDeal]

Tack on another few percent to peak for the Tour.