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Toasting bread.

post #1 of 16
Thread Starter 




He totally could have done a dark roast if the bars weren't flexing so much :)

post #2 of 16

It's nice demonstration but I would say not really real. This guy is track cyclist and even that sprinter. Top sprinters on road, after some 200+km road stage develop around 2000W in those few 100m of sprint, so I'm pretty sure he easily gets over this in his sprint, but he's not really used to hold relatively low (for sprint) wattage for long, and to make it even worse, his cadence in video was like 30rpm or something, which makes things even harder :)

I'm everything but top rider, yet I have no problem keeping (averaged) 400+W (5+W/kg) for 45-60mins (on mtb), with getting up to 800W and keeping it for 2mins during Vo2max test few years back (when I was out of pro xc ski racing for 10 years already). So for some top rider, burning toast to ash, and then burning toaster itself :) shouldn't be problem, but it would look much less spectacular then this video does... unless he would really go for burning toaster on the end. :)

post #3 of 16
Thread Starter 

Sure, his cadence was more than a little suspect; it really depends on how they set the load curve of that power converter sitting on the floor.   

It is very easy to create an electrical load that slows down the generator below its best-power rotation speed; indeed it is usually the first mistake DIY windmill operators make.

post #4 of 16

Is that what they're making cyclists like these days? OK, he's a track, not a road racer, but he looks more like a wrestler to me - carrying a lot of bulk all over. (The quads I understand )

 

Regardless, looked like he was gonna tear that poor stationary bike apart!   ;-)

post #5 of 16
Quote:
Originally Posted by jc-ski View Post

Is that what they're making cyclists like these days? OK, he's a track, not a road racer, but he looks more like a wrestler to me - carrying a lot of bulk all over. (The quads I understand )

Regardless, looked like he was gonna tear that poor stationary bike apart!   ;-)

Track sprinters have always looked like that. We cycled a good deal with the regional Keirin guys when I lived in Japan... A couple guys looked very much like the gentleman in the vid. They don't climb well (still better than most rec riders though), but on the track, you feel like a mouse being swatted around by a very large cat. One guy was always in the top 3-5 earners in the prefecture according to public tax roles they'd publish at the end of the fiscal year. That means everyone. Doctors, lawyers, etc... Those legs made bank.
post #6 of 16
Thread Starter 

I *still* think ^that^ was a ridiculous amount of handlebar motion.    Most of it seems to be coming from the 'stem' clamp/adjustment mechanism.    Good thing it was a stationary bike.

 

post #7 of 16
Quote:
Originally Posted by cantunamunch View Post

I *still* think ^that^ was a ridiculous amount of handlebar motion.    Most of it seems to be coming from the 'stem' clamp/adjustment mechanism.    Good thing it was a stationary bike.


 

No argument there.
post #8 of 16

Maybe that was a production choice, to enhance the "beast" vibe?  ;-)

post #9 of 16

Speaking of beasts, a little perspective, one horsepower is 746 Watts.

 

From Wikipedia https://en.wikipedia.org/wiki/Horsepower

 

Watt determined that a pony could lift an average 220 lbf (0.98 kN) 100 ft (30 m) per minute over a four-hour working shift.[11] Watt then judged a horse was 50% more powerful than a pony and thus arrived at the 33,000 ft·lbf/min figure.[12][better source needed]Engineering in History recounts that John Smeaton initially estimated that a horse could produce 22,916 foot-pounds per minute.[citation needed]John Desaguliers had previously suggested 44,000 foot-pounds per minute and Tredgold 27,500 foot-pounds per minute. "Watt found by experiment in 1782 that a 'brewery horse' could produce 32,400 foot-pounds per minute." James Watt and Matthew Boulton standardized that figure at 33,000 the next year.[13]

 

Most observers familiar with horses and their capabilities estimate that Watt was either a bit optimistic or intended to underpromise and overdeliver; few horses can maintain that effort for long[citation needed]. Regardless, comparison with a horse proved to be an enduring marketing tool.

 

In 1993, R. D. Stevenson and R. J. Wassersug published an article calculating the upper limit to an animal's power output.[14] The peak power over a few seconds has been measured to be as high as 14.9 hp.[14] However, Stevenson and Wassersug observe that for sustained activity, a work rate of about 1 hp per horse is consistent with agricultural advice from both 19th and 20th century sources.[14]

 

When considering human-powered equipment, a healthy human can produce about 1.2 hp briefly (see orders of magnitude) and sustain about 0.1 hp indefinitely; trained athletes can manage up to about 2.5 hp briefly[15] and 0.3 hp for a period of several hours

post #10 of 16
Quote:
Originally Posted by primoz View Post
 

It's nice demonstration but I would say not really real. This guy is track cyclist and even that sprinter. Top sprinters on road, after some 200+km road stage develop around 2000W in those few 100m of sprint, so I'm pretty sure he easily gets over this in his sprint, but he's not really used to hold relatively low (for sprint) wattage for long, and to make it even worse, his cadence in video was like 30rpm or something, which makes things even harder :)

I'm everything but top rider, yet I have no problem keeping (averaged) 400+W (5+W/kg) for 45-60mins (on mtb), with getting up to 800W and keeping it for 2mins during Vo2max test few years back (when I was out of pro xc ski racing for 10 years already). So for some top rider, burning toast to ash, and then burning toaster itself :) shouldn't be problem, but it would look much less spectacular then this video does... unless he would really go for burning toaster on the end. :)


Just sayin..

 

post #11 of 16
Thread Starter 
Quote:
Originally Posted by jc-ski View Post
 

Maybe that was a production choice, to enhance the "beast" vibe?  ;-)



I often am cynical enough to think such things.    In  this instance the cynicism is refocused -  I don't really think they enough parts choice to be tempted by your scenario.    

The actual bicycle part (handlebar) is rigid - enough cyclists have demanded more rigid bars (remember Cipo moaning about how much his bars flexed?) that getting that right is easy.        I'm guessing the people that buy that brand of stationary bike are either generally weaker or less vocal or storing the bike in the basement. 

post #12 of 16
Quote:
Originally Posted by cantunamunch View Post
 



I often am cynical enough to think such things.    In  this instance the cynicism is refocused -  I don't really think they enough parts choice to be tempted by your scenario.    

The actual bicycle part (handlebar) is rigid - enough cyclists have demanded more rigid bars (remember Cipo moaning about how much his bars flexed?) that getting that right is easy.        I'm guessing the people that buy that brand of stationary bike are either generally weaker or less vocal or storing the bike in the basement. 


Meh..most people riding exercise bikes are trying for aerobic fitness..cadence around 80-90rpm..easy gears..that kinda thing.  Guys like that, big sprinters, they're getting bulk in the gym..doing 300lb squats.  And they're very adjustable..which leads to flex issues as well.

post #13 of 16

Scott43 I know these numbers ;) But there's quite few things to consider with this. First, this guy is something like 40kg :D (ok a bit over 60 for real, but still extremely low weight). With this, he was averaging around 5.5W/kg for this section, AND!! he already had few 100km in his legs just that day with maybe still some km to go after this climb, it was way over +30c, and 13 stages of TdF before this (some 2000km) and yet another 7 to come, so this was far from maximum effort.

post #14 of 16
Quote:
Originally Posted by primoz View Post

Scott43 I know these numbers wink.gif But there's quite few things to consider with this. First, this guy is something like 40kg biggrin.gif (ok a bit over 60 for real, but still extremely low weight). With this, he was averaging around 5.5W/kg for this section, AND!! he already had few 100km in his legs just that day with maybe still some km to go after this climb, it was way over +30c, and 13 stages of TdF before this (some 2000km) and yet another 7 to come, so this was far from maximum effort.

I'll take your 60 and raise you 30. Robert Forstermann is about 90kg. Here he is squatting 2 x 260kg


Yes... I'm a weakling.



Edited by markojp - 6/12/15 at 11:42pm
post #15 of 16

Markojp I was thinking Chris Anker Sorensen, who's data from SRM were here on graph from Scott43. For Forstermann I know he's not really "lightweight", but neither of guys on track are :)

post #16 of 16
I know. Was just having fun. smile.gif
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