We still don’t really know how bicycles work

Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.

Let’s be honest, a bit of the pleasure at Chris Froome’s victory in the Tour de France is down to this being our second victory in a row and to the thought that the French haven’t won it since 1985. What must be worse for them, though, is that when it comes to the science of team cycling, even the Belgians are in front.
 
At the University of Mons, researchers are developing something called the Anaconda. It’s never going to be much of a speed machine because it is, in effect, a chain of monocycles with handlebars. These units are connected, by means of hinges that allow them to snake along, to a normal two-wheeled bike at the front. Every rider in the chain can be going in a slightly different direction, which means it takes an enormous amount of control and collaboration to move the thing forward. According to Olivier Verlinden, chief engineer on the project, the main qualification for riders is to be unafraid of falling off.
 
It’s fun, apparently. The idea is to unleash it as a beach-resort bike, the kind of thing that stag and hen parties will use to terrorise seaside towns across the world. But it is also scientifically interesting. Why? Because we still don’t really know how bicycles work.
 
It is rare that most people appreciate the bicycle, but it is quite an extraordinary machine. Push a riderless bike, letting it roll freely at high enough speeds, and it can withstand pushes from the side – it will wobble a little, but quickly recover. In the conventional analysis, that is because the gyroscopic force of the front wheel, its mass and the spontaneous turn of the handlebars all act together to keep the bicycle rolling forwards. This has something to do with the gyroscopic effect, the force that keeps a spinning top upright. You can feel this by removing a wheel from your pushbike and spinning it while you hold the axle spindles. If you try to change the orientation of the wheel, you’ll feel it push back against you.
 
The first mathematical analysis of bicycles suggested that this is also what keeps a moving bike on its wheels. But although the equations were written down in 1910, physicists always had nagging doubts about whether this was the whole story.
 
The most definitive analysis came exactly a century later. It involved an experimental bicycle that had all its gyroscopic effects cancelled out by a system of counter-rotating wheels. The effort of building such a strange contraption was worth it: the resulting paper was published the prestigious journal Science.
 
The publication plunged bicycle dynamics back into chaos. It turns out that taking into account the angles of the headset and the forks, the distribution of weight and the handlebar turn, the gyroscopic effects are not enough to keep a bike upright after all. What does? We simply don’t know. Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.
 
And it may not be solved any time soon; very few researchers are working full-time on bicycle dynamics and there’s very little money in it. Once we’ve discovered exactly how these contraptions work, it might be possible to come up with bold new designs of bicycle – perhaps even better than the Anaconda. But nobody is desperate for that to happen; not even the French.
 
Maybe that’s OK. In an age where we have worked out the history of the cosmos and the secret of life, it’s rather nice that the humble bicycle keeps our feet on the ground. 
 
Cyclists during the Tour de France. Photo: Getty

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At The Edge of Uncertainty: 11 Discoveries Taking Science By Surprise.

This article first appeared in the 29 July 2013 issue of the New Statesman, Summer Double Issue

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Why it's a mistake to assume that Jeremy Corbyn has already won

The shadow chief secretary to the Treasury on why the race to be Labour's leader is far from over.

They think it’s all over.

But they’re wrong.

The fat lady has yet to sing.

The commentary and reporting around the Labour party leadership campaign has started to assume we have a winner already in Jeremy Corbyn. The analysis, conjecture, predictions/complete guesswork about what happens next has begun in earnest. So we have seen speculation about who will be appointed to a Corbyn shadow cabinet, and “meet the team” pieces about Jeremy’s backroom operation.

Which is all very interesting and makes for the usual Westminster knockabout of who might be up and who might be going in the other direction pdq...

But I think it’s a mistake to say that Jeremy has already won.

Because I hear that tens of thousands of Labour party members, affiliates and registered supporters are yet to receive their ballot papers. And I am one of them. I can’t remember the last time I checked my post quite so religiously! But alas, my papers are yet to arrive.

This worries me a bit about the process. But mostly (assuming all the remaining ballots finally land in enough time to let us all vote) it tells me that frankly it’s still game on as far as the battle to become the next leader of the Labour party is concerned.

And this is reinforced when we consider the tens of thousands who have apparently received their papers but who have yet to vote. At every event I have attended in the last couple of weeks, and in at least half of all conversations I have had with members across the country, members are still making their minds up.

This is why we have to continue fighting for every vote until the end – and I will be fighting to get out every vote I possibly can for Yvette Cooper.

Over the campaign, Yvette has shown that she has a clear vision of the kind of Britain that she wants to see.

A Britain that tackles head-on the challenges of globalisation. Instead of the low-wage low-skill cul-de-sac being crafted by the Tories, Yvette's vision is for 2m more high skill manufacturing jobs. To support families she will prioritise a modern childcare system with 30 hours of fully funded child care for all 3 and 4 year olds and she will revive the bravery of post war governments to make sure 2m more homes are built within ten years.

It's an optimistic vision which taps into what most people in this country want. A job and a home.

And the responses of the focus groups on Newsnight a few days ago were telling – Yvette is clearly best placed to take us on the long journey to the 2020 general election by winning back former Labour voters.

We will not win an election without winning these groups back – and we will have to move some people who were in the blue column this time, to the red one next time. There is no other way to do it – and Yvette is the only person who can grow our party outwards so that once again we can build a winning coalition of voters across the country.