Power Data Estimates for the climbing stages

[Le breton]

http://www.cyclismas.com/2013/05/giro-climbs-performances-in-pictures/

The Col du Télégraphe road is generally well protected from the wind.

For the Galibier climb itself, from the lowest point in Valloire at 1401 meters(bridge over the mountain stream) you first go through the village, then reach a flattish area in Les Verneys where the flags indicated a pretty strong headwind. I have once experienced such conditions there and I remember actually waiting for other riders to get some help. After the bridge in Plan Lachat (1984 meters) the road gets steeper and wind is far less of a factor.

Anyway, the flags in Les Verneys discouraged me from trying to calculate Watts/kg.

 

[Le breton]

Nibali TT today

I am busy and don't really have time to make a detailed calculation.

So I took a Bahamontes like cyclist able to do 6.4 watts/kg on a 40 min effort and asked analyticcycling what his split time would be at the 9.45 km intermediate marker today.

I lumped together the first 1.4 km from 187 to 202 m. a.s.l. and
the last 750 meters from 692 to 695 meters

for a total of 2 150 meters climbing at 0.84%

The rest is 7.3 km at 6.71%.

At 6.4 watts/kg, for 75 kg total (67+8), it means 429 watts on the pedals and 418 watts at the rear wheel.

I took 15°C and air dens. 1.17 at average altitude of 700m.
Crr=0.004, no allowance for rain or wind.

Result for CdA = 0.31 m^2 on flattish part
CdA = 0.375 uphill.

Result 10 sec (start) + 180 sec (flattish) 1086 sec (uphill) = 1276 sec.

i.e. 21'16".

Nibali, 20'49" I believe, must have been a bit above 6.5 watts/kg.

L.A. all doped up AdH was at 6.76 watts/kg during his first 20 min or so to the 1st time check at 1395 m a.s.l.

You can start poking holes

 

[131313]

The rest is 7.3 km at 6.71%.


Crr=0.004, no allowance for rain or wind.

Result for CdA = 0.31 m^2 on flattish part
CdA = 0.375 uphill.


You can start poking holes

OK, I'll start. I think your Crr and CdA estimations are both overstated, CdA is significantly overstated. He was seated for a lot of the climb and in the bars for a fair bit of it as well. And, he's a small guy. I'd say .26 for the flat parts and .30 averaged for the uphill would be more reasonable, with the understanding that he's higher than than on the steeper bits where it matters less, and less than that where it matters more. Even 3.0 may be an overestimation. I also think Crr would be closer to .30. The road service was good and I imagine he was on VF Records for a HC TT.

Still, he certainly put out gobs of power.

 

[Merckx index]

Nibali, 20'49" I believe, must have been a bit above 6.5 watts/kg.

Even relaxing your assumptions, well above the 6.0 or so that is supposed to be the standard for the "clean era". Granted, 20 minutes is relatively short, but he couldn't go all out given that was less than half the ride. He had to leave something for the remaining climb. Also, Ferrari estimated 6.4 W/kg for Nibs on the Montasio, about a thirty minute climb.

 

[Netserk]

Doesn't Ferrari always estimate too big numbers?

EDIT: I get 6.0 W/kg (31'46) for Montasio.

 

[SeriousSam]

Doesn't Ferrari always estimate too big numbers?

EDIT: I get 6.0 W/kg (31'46) for Montasio.

6.0? Are you sure it isn't 5.99 because that would still be believable!

 

[Le breton]

OK, I'll start. I think your Crr and CdA estimations are both overstated, CdA is significantly overstated. He was seated for a lot of the climb and in the bars for a fair bit of it as well. And, he's a small guy. I'd say .26 for the flat parts and .30 averaged for the uphill would be more reasonable, with the understanding that he's higher than than on the steeper bits where it matters less, and less than that where it matters more. Even 3.0 may be an overestimation. I also think Crr would be closer to .30. The road service was good and I imagine he was on VF Records for a HC TT.

Still, he certainly put out gobs of power.

The calculation is not for Nibali since I don't know his weight, it's for a generic rider of 67 + 8 kg. Have not seen the images, my usual TV channel didn't show the stage today.

Crr of 0.003 you mean? Sounds extremely low. Was it a wet cement road? I am not aware that it can be as low as 0.003 on a dry asphalt road, I measured 0.0036 on a rather good dry French road (up La Faucille, km 3 to 8) with Vittoria Evo Cx sew-ups.

Also, didn't make allowance for the extra weight added by the wet clothe, etc.

PS : at 60 kg, I have a CdA of 0.31 m^2 with my regular road bike. Anyway, that part represents only about 3 min.
Going uphill, mixed position, I am above 0.35 m^2, just saying.

 

[Le breton]

Even relaxing your assumptions, well above the 6.0 or so that is supposed to be the standard for the "clean era"......

Yes, but 6.0 max is for the LAST CLIMB of a hard mountain stage. IIRC Moncoutié was at 6.2 up AdH in 2004 (TdF)

 

[whittashau]

I would be interested to see a comparison between Nibali's performance today and Contador's performance during the MTT at the 2011 Giro.

 

[Netserk]

I would be interested to see a comparison between Nibali's performance today and Contador's performance during the MTT at the 2011 Giro.

Contdor did 6.3 W/kg from the split to the end of the stage.

Time: 20:58

So a FTP of 5.985?

 

[whittashau]

I was just reading Cameron Wurf's blog and came across an interesting comment:

"I settled on 365 watts as I predicted I would loose around 8 minutes which would see me safely inside the 30% or around 14minute time limit for today. Sure enough I pushed this power from the first pedal stroke to the last and sure enough lost 7:50 so my calculations were pretty accurate. The best part about this calculation is I worked back from what I had been planning on trying to produce to go for a top result today, that being around 430 watts or 6-6.5watt/kg so at least if nothing else I was pretty accurate with predicting what was required to feature at the pointy end today"

So he certainly wasn't surprised by the winning result, and even felt he could have maybe produced such a performance if he were in form.

 

[Ferminal]

Yeh ok Cam, I can't wait for the Wurf-Basso 1-2 next year

His range for the winner sounds like a good guess though. Based on the drips of info we get it seems that 6.2-6.5 is what gets you close to the win against the clock?

Is it possible that we undervalue the effect of 4-5hours riding before an MTF? Given the range there is usually 5.8-6.0.

 

[whittashau]

Yeh ok Cam, I can't wait for the Wurf-Basso 1-2 next year

His range for the winner sounds like a good guess though. Based on the drips of info we get it seems that 6.2-6.5 is what gets you close to the win against the clock?

Is it possible that we undervalue the affect of 4-5hours riding before an MTF? Given the range there is usually 5.8-6.0.

I think people are undervaluing the affect

As for Cam assessment on his own abilities, he seems like a really honest guy based on reading his blog and seems to fully disclose everything including admitting his many faults. In fact it's one of the best cyclist blogs I've read. One of the most interesting things I've read on there is that he has independently decided to take on the Wiggo/Sky model of measuring his efforts based on his SRM. Furthermore, he's suggested on there several times that he never really has been able to translate his great training numbers into races. I guess that's another thing he and Wiggo have in common.

 

[Dear Wiggo]

I think it goes like this:

6W/kg for the hour (FTP) means for efforts < 60 minutes, the W/kg will be higher.

When a rider does 6W/kg up that final hill in a 160+km race, it's rarely for an hour. He'd ride up the same climb with better power fresh.

If the TT is 60+ minutes, you'd still expect 6W/kg.

There's only a couple making that figure look weak.

 

[BigBoat]

Is it possible that we undervalue the effect of 4-5hours riding before an MTF? Given the range there is usually 5.8-6.0.

Depends on a myriad of factors at the end of 5 hour race I suppose, but for the mountain time trial we can more accurately determine the top riders FTPs. I could assume in my mind if Nibali averaged 6.3 w/kg over 42 mins on stage 18 of a 2,200 mile race his completely fresh FTP (assuming identical conditions while being rested) is 6.3 w/kg. Those identical conditions could be any oxygen carrying products he'd used, any transfusions he used beforehand, etc.

 

[rata de sentina]

Is it possible that we undervalue the effect of 4-5hours riding before an MTF? Given the range there is usually 5.8-6.0.

Undervalue? Those 4-5 hours usually include a number of c2, c1 or even hc climbs so that's hard to undervalue.

 

[Ferminal]

Thanks for the post BB.

Undervalue? Those 4-5 hours usually include a number of c2, c1 or even hc climbs so that's hard to undervalue.

That's what what I thought. But Tucker for example believes the difference isn't great and is happy to compare MTTs and road stages, most notably Armstrong 2004 Alpe d'Huez which is often a benchmark for what can't be achieved now. Yet Armstrong never really went beyond 6.2-6.3 at the end of a stage.

 

[Le breton]

Thanks for the post BB.
That's what what I thought. But Tucker for example believes the difference isn't great and is happy to compare MTTs and road stages, most notably Armstrong 2004 Alpe d'Huez which is often a benchmark for what can't be achieved now. Yet Armstrong never really went beyond 6.2-6.3 at the end of a stage.

Come on.
Just one example : his AdH 2001 in 38'01. I won't redo the calculation right now, but that is well above 6.5 W/kg.
Against 37'36" in his AdH 2004 TT where he was in the neighborhood of 6.7-6.8 W/kg

EPO allows that: to be just as fresh at the start of the last climb as if you had just gotten out of bed, gone for a warm-up, and jumped on your bike.

 

[Ferminal]

If you calculate a 38 minute Alpe d'Huez to be >6.5 W/kg then Sastre was >6.2 W/kg in 2008 and >6.4 W/kg in 2006 (both were 3rd week) therefore based on that alone we can call him a doper.

 

[Alex Simmons/RST]

I also think Crr would be closer to .30. The road service was good and I imagine he was on VF Records for a HC TT.

Must be very very smooth roads for a Crr < 0.004

What were the wind conditions?

keep in mind they were not using full aero kit.

What are guesstimates ranges for assumed inputs; mass, CdA, Crr, wind, air density, and what sort of a range for the W/kg calculation does that make for?

How variable was the gradient over the course? For a course of this duration I usually generate ~ 75 individual segments.

 

[Le breton]

What were the wind conditions?
I would have liked to know, however, from looking at the course it seems unlikely to be a potential pb for calculations.

How variable was the gradient over the course? For a course of this duration I usually generate ~ 75 individual segments.

I don't know if 131313 made a calculation or not., but it's obvious to me that dividing those 9450 m in 75 segments would be gross overkill considering you can't hope for a representative result at better than a 3-4% ! given the lack of knowledge about wind, the effect of rain and the usual suspects.

 

[BigBoat]

Come on.
Just one example : his AdH 2001 in 38'01. I won't redo the calculation right now, but that is well above 6.5 W/kg.
Against 37'36" in his AdH 2004 TT where he was in the neighborhood of 6.7-6.8 W/kg

EPO allows that: to be just as fresh at the start of the last climb as if you had just gotten out of bed, gone for a warm-up, and jumped on your bike.

True Lance's power from those years was higher than now with Nibali....

BUT what was the 2nd place rider's power from that year (Ullrich). What did Basso do in 2004? What did Mancebo do during those years or Vino...they were all talented dopers. What was the winning TT power at the Tour when Lance left, if I remember Floyd's coach ventura had all of Floyd's power data live and was rambling on sporadically during the TV coverage that year....FTP 400, 6.0 w/kg.

 

[Tyler'sTwin]

Impressive.

#Giro, Stage 18, ITT (2.5→8.7=6.2 km + last 6.4 km). Vincenzo Nibali: 31:13. DrF: 6.13 W/kg. CPL: 6.42 W/kg. BCL: 6.53 W/kg. rst: 6.57 W/kg.

https://twitter.com/ammattipyoraily/status/337883648860770305

 

[Tyler'sTwin]

Power outputs are clearly higher in TT's.

2011 Paris-Nice, Stage 6: Rognes - Aix-en-Provence (ITT) 27km

Rigoberto Uran's data:

Time: 35:50
Body Weight: 138lbs (63kg)
Average Watts: 389w (395np)

http://home.trainingpeaks.com/races/team-sky-races/paris-nice-2011/stage-6---rigoberto-uran.aspx

6.17 W/kg

You don't see him pushing those numbers on a ~35min finishing climb. At least not according to estimates.

 

[Alex Simmons/RST]

What were the wind conditions?
I would have liked to know, however, from looking at the course it seems unlikely to be a potential pb for calculations.

How variable was the gradient over the course? For a course of this duration I usually generate ~ 75 individual segments.

I don't know if 131313 made a calculation or not., but it's obvious to me that dividing those 9450 m in 75 segments would be gross overkill considering you can't hope for a representative result at better than a 3-4% ! given the lack of knowledge about wind, the effect of rain and the usual suspects.

Overkill? Perhaps but this was hardly a consistent gradient climb:
via Inrng: