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Comment by DoofusOfDeath | Hacker News Reader

I'm trying to understand the magnitude of her accomplishment.

Based on the help she got from the car and the bike's unusual gearing, it sounds like her main athletic accomplishment was to accelerate a bike by 83.9 MPH.

Am I missing something?

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Accelerating a pedal-powered bike by 135kph / 83mph is a stunning accomplishment. I am flabbergasted that you don't see that as something notable.

> Accelerating a pedal-powered bike by 135kph / 83mph is a stunning accomplishment. I am flabbergasted that you don't see that as something notable.

I just don't know either way. I would imagine it comes down to how much time or distance she had to accomplish that acceleration.

Because without significant wind resistance, and with appropriate gearing ratios on the bike, honestly I just don't know what else would be physically demanding.

> As Holbrook accelerates, the cyclist will push 700 watts for more than a minute to stay inside the draft pocket behind the dragster’s fairing. That’s about what a Tour de France sprinter produces in the final minute of a stage.

From https://www.wired.com/story/denise-mueller-korenek-bike-spee... - 700W over a minute is very physically demanding.

She's a world champion athlete. You're seriously underestimating her physical prowess.

And maintaing the balance at those speeds. I can hardly control mine at 50 kmph downhill

> And maintaing the balance at those speeds. I can hardly control mine at 50 kmph downhill

Wouldn't balance actually be easier, due to the gyroscopic effect of how fast the wheels would be turning?

The gyroscopic effect is not what causes a bike to balance, it's the arrangement of centres of mass around the pivot or steering. It is harder to maintain that balance at high speeds since small adjustments to the steering produce much quicker responses.

https://ezramagazine.cornell.edu/SUMMER11/ResearchSpotlight....

That's highly inaccurate. The gyroscopic effect is not everything, but it does get stronger at higher speeds. That's why even a simple wheel without any frame or steering mechanism will run mostly stable at high speeds. So when going at high speeds on a bike, it indeed is more stable than when going slow.

The article you link only claims that the gyroscopic effect is not everything stabilizing a bike.

That's a problem with your posture and/or your bike's geometry (or just a loose headset), not an inherent problem of going 50 kmph

Beside what has already been said, I'm pretty sure wheels turning at those speed cause an enormous amount of friction. And they're spoked, that has to turbolence!

Post a video when you do it. :P

This is a really unproductive class of response to criticism.

It's unreasonable and pointlessly limiting to restrict criticism to people who can potentially replicate the results. Also the ad hominem aspect really sours the mood.

It depends on what it is a response to. If someone says that a particular feat is no accomplishment and easily replicable for essentially anybody (not e.g. in comparison to other participants), it doesn’t strike me as too unreasonable to call the person claiming it out on that.

Sports are different from, say, someone criticizing art that way, where an appropriate response to “I could have done that” is often “but you didn’t”.

But in this case that commenter did not say "anyone could have done it". My interpretation of that comment was that the actual accomplishment is different (and lesser in terms of athleticism) from what the headline suggests. Does that deserve a "but you didn't" rejoinder?

FWIW I wasn't even criticizing. I was just trying to get my mind around the physics of it all.

Post a comment when you have a good one. :P

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