Re: Science of cycling still largely mysterious

On 5/21/2025 10:43 AM, Wolfgang Strobl wrote:

Am Tue, 20 May 2025 11:44:29 -0400 schrieb Frank Krygowski
<frkrygow@sbcglobal.net>:
 

"Science of cycling still largely mysterious"
>
This article from 2016 recently popped up again:
https://www.cbc.ca/news/science/science-of-cycling-still-mysterious-1.3699012

 Somewhat dubios.
 On the one hand "While many people know how to ride a bike, we know
surprisingly little about the science of how cycling actually works,
says CBC columnist Torah Kachur" (under a picture that display some kind
of oval biopace chain ring). Continued with "But the science of staying
upright on two wheels is anything but simple — and we know surprisingly
little about the intricacies of how cycling actually works."
 On the other hand "But it's the physics that are really fascinating, and
somewhat mysterious — the forces that keep a bike going, the variables
that make one bike better than the rest, why a riderless bike seems to
be able to stay up and ride straight, and what the best design really
is." and a lot of repetitions of that mantra.  Shure, its fascinating,
but _these_ questions have been studied and answered quite a lot in the
past, as far as they are indeed physical or engineering questions.
 Actually, quite some questions which haven't been studied or are
somewhat open aren't about the physics of cycling, but are questions of
biological or medical nature, that haven't been studied in depth, and
sometimes they haven't been asked at all, so far.  With other words, it
is not about the bicycle, but about the person riding it, where we have
blind spots.   We don't have to look far for finding an example.  What
is the function of a saddle? How does it work? What makes a good saddle?
Ask two people and get three answers, most probably all wrong, in a way.
:-)
 The hypothesis behind "Take the riderless bike, for example. You can
push a bike along a path and it almost self-steers. It can recover from
wobbles to stay upright. That's ultimately the physics behind why bikes
are easy to ride, and yet we know precious little about how that
actually works" has been refuted by Jobst Brandt more than once.  The
question why and how a _riderless_ bicycles stays uprigt for a while
might be interesting and hard to solve - but it doesn't have anything to
do with how a rider stays upright on a bicycle. Gyroscopic effects don't
have much to do with it, so much is obvious.
 There is one paragraph in the whole article that I wholeheartedly agree
with, it's the one at the very end
 | That being said, the bike is a well-designed machine
| because the best machine is still the rider on top of it.
| The best shock absorber is the bent arms of the rider,

I take exception with that, given how a hard tail transmits impacts directly into ones ischial tuberosities.
A full suspension bike is far more efficient over rough terrain in terms of speed and comfort.
and

| the best generator of a forward force is the power of the
| legs behind it.