How will Jens Voigt prepare his hour record attempt ?

[UncleChainwhip]

Seem to remember Jens giving Boardman some stick in the Duo Normand. Those Swiss velodromeHVAC engineers just might be 'fans'…….double entendre intended

 

[ralphbert]

Now it when you go searching for that pot of treasure and reap the rewards. its genius. pure genius. well done jens. well done legs

That explains his fixation with Geocacheing

 

[ralphbert]

400W would bring him close to the 53k mark assuming a good 0.20-0.21 SCx.
That's a lot, Wiggins or Luigi will have to work hard to beat him !

But it's not only about the legs, I doubt he'll be easy riding on a track, remember Indurain, even with his 510w (estimated by Padilla, 6.5+ w/kg ), was ridiculous when Rominger beat him twice.

Using this tool:
http://www.cyclingpowerlab.com/timetrialanalysis.aspx

It has a CdA for Yens @ 0.2492 = 443w to break the record. So yeah, that's not going to be much fun.

I'm not sure where there CdA's are from or how accurate they are

Just recalculated using power at crank & on wooden track = 408.43W. So possible but wow, it is going to hurt.

 

[Fausto's Schnauzer]

I wonder how often he'd dig into his suitcase of courage?

 

[D-Queued]

Using this tool:
http://www.cyclingpowerlab.com/timetrialanalysis.aspx

It has a CdA for Yens @ 0.2492 = 443w to break the record. So yeah, that's not going to be much fun.

I'm not sure where there CdA's are from or how accurate they are

Hmm...

Wonder how they estimate those numbers.

Jens & I are about the same ht/wt. My 'measured' CdA is just a wee bit (!) higher than that.

Recall that Indurain, also about the same ht & wt, needed 508 watts...

Dave.

 

[Archibald]

are they even going to bother to test him?

 

[ralphbert]

See the above edit. Remember Indurain wasn't on a TT bike but a track bike and was going for a record with higher speed.

 

[ralphbert]

Hmm...

Wonder how they estimate those numbers.

Jens & I are about the same ht/wt. My 'measured' CdA is just a wee bit (!) higher than that.

Recall that Indurain, also about the same ht & wt, needed 508 watts...

Dave.

See the above edit. Remember Indurain wasn't on a TT bike but a track bike and was going for a record with higher speed.

 

[D-Queued]

See the above edit. Remember Indurain wasn't on a TT bike but a track bike and was going for a record with higher speed.

You lost me a bit on that.

Track bike?

You mean like this:

Under the latest UCI rule change (don't you just love those...), Jens is not restricted to the previous Merckx style bike rule. Though may not be able to employ an Indurain bike.

Thanks for editing your previous post. Yes, the drag numbers seem wonky

In any event, I still believe that Jens needs more oomph than 408 watts to have any shot at all. He probably has a frontal area of around .4m2 or so, and a CdA approaching 0.6.

In terms of previous efforts.

Merckx trained at 475 watts for an hour for Mexico.

Boardman was recorded or estimated to have ridden at ~450.

Indurain was estimated at 508.

Thus, an educated guess (and a lot of wind tunnel time) says that a big guy like Jens needs no less than 450 to set the record even with a more aero set up than Eddy as allowed by the recent rule change.

Dave.

 

[blackcat]

Seem to remember Jens giving Boardman some stick in the Duo Normand. Those Swiss velodromeHVAC engineers just might be 'fans'…….double entendre intended

needs to come to Adelaide in Summer when the Oz records are all set. Better conditions at del Monte than the Colombia track that Hoy et al attempted to set the 1km WR even tho the Colombia track in Santiago or wherever is altitude, and better than the Russian Moscow 350metre track for the sprinters with the vertical banking... As long as you can deal with the heat, I think that is where Jacky Bobby set his 4'11" IP wr? corrections anyone?

 

[blackcat]

That explains his fixation with Geocacheing

yes, indeed.

Jens treasure hunt ftw

I wonder if Jens is gonna miss Jaja's potbelge and coke parties in Cannes? Surely he will. Surely that is why he hung on longer than Dmitri Konychev and Stuart OGrady

oh, and the hookers

 

[Alex Simmons/RST]

Hmm...

Wonder how they estimate those numbers.

Jens & I are about the same ht/wt. My 'measured' CdA is just a wee bit (!) higher than that.

Recall that Indurain, also about the same ht & wt, needed 508 watts...

Dave.

I've measured fairly large differences (e.g. 20%) in CdA between riders of same height and mass using same equipment set ups.

While there are some basic principles, in general the eye makes a really poor wind tunnel.

 

[Alex Simmons/RST]

needs to come to Adelaide in Summer when the Oz records are all set. Better conditions at del Monte than the Colombia track that Hoy et al attempted to set the 1km WR even tho the Colombia track in Santiago or wherever is altitude, and better than the Russian Moscow 350metre track for the sprinters with the vertical banking... As long as you can deal with the heat, I think that is where Jacky Bobby set his 4'11" IP wr? corrections anyone?

Heat is a big problem for hour record attempts and can result in a loss of power output greater than the benefit attained from reduced air density. We had this problem for one of my guys when we struck a particularly hot day.

A pursuit is over and done with well before the rider has a chance to suffer performance degradation as a result of overheating. Bobridge set his world record at DGV in Sydney 2011. I raced at the same championships and it was blazing hot.

Sydney is one of the fastest track surfaces in the world but is, like Adelaide, a sea level track, and no artificial climate control systems. Adelaide track has tighter turn radius than Sydney (IOW has longer straights), and I suspect likely a marginally slower track.

The Adelaide track is not at Del Monte. It's at Gepps Cross.

 

[Digger]

Dope

already been named by Joerg.

Yet he's a hero to many.

Fine, but don't pretend he's not doping.

 

[jens_attacks]

But the cycle development has also got his thoughts on an attack on the time trial world record again. "I asked Cecchini the other day: How many watts can I produce during one hour of cycling, if I'm prepared in the best way? Between 500-520 watts he said. It's hard to tell, but it's close the mentioned figures. We just made some calculations which shows, that if I ride under optimal conditions (the track, the wind, the bike), then I have to produce between 515 and 518 watts to ride the 57 km necessary to break the record". Riis smiles, puts his hand horizontally in the air, and lets his hand go up and down. "It'll be close, and it's also possible that it can't be done. In january I totally knocked it out of my head, because I didn't believe I could do it. But after the latest test, I've begun to wonder again. I have to improve my aerodynamic position on the bike, so I get more power out in the pedals. Correct a couple of other details. But then I'm close I'm sure. And I would like to try... Just once"


more than 7 w/kg for one hour no problem those were the days.

 

[melkemugg]

He does not seem too serious about it to be honest. It looks more like a PR campaign for a bike and to lure others to attempt it.

 

[lllludo]

Hmm...
Wonder how they estimate those numbers.

to estimate you have to adjust the formula to a totally flat(?) environment, new frictional forces, altitude, air T° and most importantly new Cx (aerodynamism)

check this link: http://www.rst.mp-all.de/leistung.htm

 

[D-Queued]

I've measured fairly large differences (e.g. 20%) in CdA between riders of same height and mass using same equipment set ups.

While there are some basic principles, in general the eye makes a really poor wind tunnel.

Agreed.

However, I can superimpose a picture of Wiggo over a picture of me, for example, and there is almost no discrepancy - i.e. virtually identical frontal area. The equipment is so remarkably similar we can call it identical for the purposes of discussion.

You may know better than me, but those drag numbers look low. And far more than a 20% delta.

Dave.

 

[blackcat]

Heat is a big problem for hour record attempts and can result in a loss of power output greater than the benefit attained from reduced air density. We had this problem for one of my guys when we struck a particularly hot day.

A pursuit is over and done with well before the rider has a chance to suffer performance degradation as a result of overheating. Bobridge set his world record at DGV in Sydney 2011. I raced at the same championships and it was blazing hot.

Sydney is one of the fastest track surfaces in the world but is, like Adelaide, a sea level track, and no artificial climate control systems. Adelaide track has tighter turn radius than Sydney (IOW has longer straights), and I suspect likely a marginally slower track.

The Adelaide track is not at Del Monte. It's at Gepps Cross.

thanks for reply

 

[Alex Simmons/RST]

Agreed.

However, I can superimpose a picture of Wiggo over a picture of me, for example, and there is almost no discrepancy - i.e. virtually identical frontal area. The equipment is so remarkably similar we can call it identical for the purposes of discussion.

You may know better than me, but those drag numbers look low. And far more than a 20% delta.

Dave.

I've learned to never assume a rider's aero number, only to measure it. The way air flows and creates pressure gradients is just so darn complex. Of course I have in my head a range of plausibility for a given rider and position, but it's remarkable how often one can be wrong.

On a pursuit bike at ~78kg and 182cm I was ~0.235m^2. I have large shoulders to start with.

Somewhat related - I'm off to Melbourne tonight - over the next two days I'm delivering the "Positioned for Speed" course with the Retul guys to a group of about a dozen bike fitters, where I teach the participants some of the fundamental principles of cycling aerodynamics, and the practical methodologies for aerodynamic testing at the track (they learn how to run an aero testing session). I use the Alphamantis Track Aero System.

 

[ralphbert]

I've learned to never assume a rider's aero number, only to measure it.

Off topic but in your experience can you measure CdA accurately enough using a power meter and speed analysis on a velodrome or do you need to be in a tunnel? And by measure I mean dial in a "fast" position rather than arrive at a specific CdA number.

Sorry rereading you post the obvious answer is YES.

 

[Alex Simmons/RST]

Off topic but in your experience can you measure CdA accurately enough using a power meter and speed analysis on a velodrome or do you need to be in a tunnel? And by measure I mean dial in a "fast" position rather than arrive at a specific CdA number.

Sorry rereading you post the obvious answer is YES.

If you know what you are doing, and have good quality data, then you can most definitely measure CdA with sufficient precision to make decisions about minor things, equivalent to a good wind tunnel.

Depending on various factors, I'll see standard error for each test run in the 0.001m^2 range. Repeatability of results tells me what sort of confidence to have and/or whether I need to validate inputs.

You need quality data (wheel speed, power, track geometry, precise lap timing and environmental conditions), good testing protocols and processes, and an eye for anomalies and what can cause them. Same principles apply to wind tunnels. e.g. some riders are better testers than others.

It's still possible to get pretty good results from field test without all those elements although power and speed data are essential. e.g. I have done quite a bit of testing at outdoor tracks and if conditions are relatively benign you can still do quite a bit of good testing - just precision falls away compared with the much more controlled environment attainable indoors and so it depends on how small of a change you are seeking to tease out of the data. Plus you are at the mercy of the elements.

Tunnels and track testing complement each other as each has specific advantages. Tunnels are highly controlled, and some can provide specific testing at various yaw angles, and the data is solely to do with air resistance.

Tracks mean the rider is actually on the bike riding at race pace and you can quickly see whether or not a position is viable for them, or indeed see what happens as they fatigue, something that can be harder to assess when on a fixed trainer set up. Track results are a combination of all resistance forces, so for example if you change a wheel, then the result is the combination of the air and rolling resistance changes. It is possible to split that pair, but it requires greater level of data capture, and is often not required when all the rider wants to know is "which is faster?".

As an example, here are summary results from a series of tests done during an aerodynamics teaching exercise. The consistency in results when testing same set up options is remarkable, especially considering in this session the testing runs were shortened quite a bit from what I might typically do (as it was primarily a teaching exercise).

In that chart, just so it's clear, here are the results grouped for each set up so you can see the level of repeatability of results:

0.285, 0.285
0.282, 0.281, 0.281
0.284, 0.284
0.280, 0.280, 0.280
0.267, 0.267
0.261, 0.260
0.258, 0.255
0.253, 0.252

Other data is for what I call "shrug testing" which is where we get the rider to do some specific modification of their position while riding and see how that works for them.

 

[D-Queued]

I've learned to never assume a rider's aero number, only to measure it. The way air flows and creates pressure gradients is just so darn complex. Of course I have in my head a range of plausibility for a given rider and position, but it's remarkable how often one can be wrong.

On a pursuit bike at ~78kg and 182cm I was ~0.235m^2. I have large shoulders to start with.

Somewhat related - I'm off to Melbourne tonight - over the next two days I'm delivering the "Positioned for Speed" course with the Retul guys to a group of about a dozen bike fitters, where I teach the participants some of the fundamental principles of cycling aerodynamics, and the practical methodologies for aerodynamic testing at the track (they learn how to run an aero testing session). I use the Alphamantis Track Aero System.

Hard to argue with that!

But, that is all the more reason to question how that table of drag coefficients was determined. Looks like they simply used some kind of formula based upon height and weight.

BTW - I would be ecstatic if I had your frontal area!

I would also be ecstatic if I could justify the trip, any trip, to Oz - and, of course, participate in your session.

Dave.

 

[Alex Simmons/RST]

Hard to argue with that!

But, that is all the more reason to question how that table of drag coefficients was determined. Looks like they simply used some kind of formula based upon height and weight.

BTW - I would be ecstatic if I had your frontal area!

I would also be ecstatic if I could justify the trip, any trip, to Oz - and, of course, participate in your session.

Dave.

There are various formulas based on morphology used to estimate CdA, but in the way that HRmax is never really well predicted by age-based formula, neither is CdA.

My CdA is nothing special, I'm not what you call aerodynamically gifted. I know people over 6' with CdA of ~ 0.200m^2 and one who is same height and weight as me with CdA ~ 0.190m^2.

Lowest CdA I've measured for a rider is in vicinity of 0.17m^2. Good power too for a female masters rider.

There are such sessions held in various places, they've done them in Los Angeles and I know one was held not so long back in Manchester. It takes a bit to make the whole shebang work well, and I expect that after a period of nearly 2 years of technology and process testing, I'll have most of the kinks ironed out for application down under and can do this sort of stuff more regularly.

 

[Amazinmets73]

If you gave Ulrich a sufficient amount of time to prepare, do you think he'd post a better hour time than Jens?