A few months ago I wrote an article about curling and the
mysterious element in the sport that nobody can explain, see: https://hpanwo-voice.blogspot.com/2026/02/curling-mystery.html.
I have since come across something very similar in a video by one of the most
distinctive science YouTubers, Simon Whistler, the most charismatic baldy
since... well, me. It's all about
bicycles. This is a mode of transport that is surprisingly recent. The first
one was invented in Scotland
in 1839. For such a relatively simple machine I'm surprised nobody thought of
it a long time before. For comparison, the first working steam locomotive was
invented less than forty years previously; and the first car was put on the
market barely forty years later. You'd think those two were far greater
engineering challenges. The "safety bike", one with frame mounted pedals
and a chain drive connected to a crank on the rear wheel, was first built in
the 1880's. It was so called because if you fell off it wasn't from such a
great height as you would from a penny-farthing. The safety's design worked so
well it remains fundamentally unchanged to the present day. I was therefore
very surprised when I found out that there are phenomena associated with
bicycles that cannot be explained. The simplicity of the mechanism should mean
that the physics of its function would be comprehensive to a pre-Newtonian; but
no.
A bike only has two wheels and stays upright by the rider
making constant tiny movements to its direction that counters its inevitable
imbalance. The rider can also do this by shifting their weight slightly. It
takes a while for a new rider to achieve this, but after a bit of experience
this movement becomes automatic and subconscious. This should mean that a
bicycle moving without a rider should immediately topple over, but it doesn't
always. Under some conditions a riderless bike will keep going for as long as
it has forward motion. If you push it down a hill this could be for miles. Why?
Well, one theory from the late nineteenth century is that the rotating wheels remain
in a rigid state because they are spinning, rather like a gyroscopes. This was
disputed in the 1970's. Another theory is that the front wheel acts like a
caster on a shopping trolley, slightly trailing the centre of its steering
axis; but this was eventually also discredited at about the same time. So what
is the real cause of this strange self-balancing effect; and why does it not
work on a bike with a rider? This movie clip demonstrates the difference, see: https://www.youtube.com/watch?v=HMV0PCUzkag.
Source: https://www.youtube.com/watch?v=aJkJvS2ou1E.
As with the curling conundrum, this is another example of how the very simplest
of physical systems sometimes reveal themselves to be only a thin veil of the
mundane covering the unfathomable. I like the quote at the end of the source
video by the science writer Michael Brooks. Who needs black holes and dark
matter when we have bike enigmas that evade explanation even more? Would an
equivalent of CERN be necessary for us to find out how a bicycle really works? It
makes me wonder about perpetual motion, and also the strange properties of Eric
Laithwaite's spinning wheel; see the background link. There is definitely
something fundamental about the universe we have yet to find out; and the
initial clue has come from a machine that millions of people use every day for
transport.
See here for background: https://hpanwo.blogspot.com/2020/08/free-energy-portal.html.
See here for background: https://hpanwo.blogspot.com/2020/08/free-energy-portal.html.

