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 isn't Labour putting forward Corbynite candidates?

Despite his successes as a candidate, the organisational victories have gone the way of Corbyn's opponents. 

The contest changes, but the result remains the same: Jeremy Corbyn’s preferred candidate defeated in a parliamentary selection. Afzhal Khan is Labour’s candidate in the Manchester Gorton by-election and the overwhelming favourite to be the seat’s next MP.

Although Khan, an MEP, was one of  the minority of Labour’s European MPs to dissent from a letter from the European parliamentary Labour party calling for Jeremy Corbyn to go in the summer of 2016, he backed Andy Burnham and Tom Watson in 2015, and it is widely believed, fairly or unfairly, that Khan had, as one local activist put it, “the brains to know which way the wind was blowing” rather than being a pukka Corbynite.

For the leader’s office, it was a double defeat;  their preferred candidate, Sam Wheeler, was kept off the longlist, when the party’s Corbynsceptics allied with the party’s BAME leadership to draw up an all ethnic minority shortlist, and Yasmine Dar, their back-up option, was narrowly defeated by Khan among members in Manchester Gorton.

But even when the leadership has got its preferred candidate to the contest, they have been defeated. That even happened in Copeland, where the shortlist was drawn up by Corbynites and designed to advantage Rachel Holliday, the leader’s office preferred candidate.

Why does the Labour left keep losing? Supporters combination of bad luck and bad decisions for the defeat.

In Oldham West, where Michael Meacher, a committed supporter of Jeremy Corbyn’s, was succeeded by Jim McMahon, who voted for Liz Kendall, McMahon was seen to be so far ahead that they had no credible chance of stopping him. Rosena Allin-Khan was a near-perfect candidate to hold the seat of Tooting: a doctor at the local hospital, the seat’s largest employer, with links to both the Polish and Pakistani communities that make up the seat’s biggest minority blocs.  Gillian Troughton, who won the Copeland selection, is a respected local councillor.

But the leadership has also made bad decisions, some claim.  The failure to get a candidate in Manchester Gorton was particularly egregious, as one trade unionist puts it: “We all knew that Gerald was not going to make it [until 2020], they had a local boy with good connections to the trade unions, that contest should have been theirs for the taking”. Instead, they lost control of the selection panel because Jeremy Corbyn missed an NEC meeting – the NEC is hung at present as the Corbynsceptics sacrificed their majority of one to retain the chair – and with it their best chance of taking the seat.

Others close to the leadership point out that for the first year of Corbyn’s leadership, the leader’s office was more preoccupied with the struggle for survival than it was with getting more of its people in. Decisions in by-elections were taken on the hop and often in a way that led to problems later down the line. It made sense to keep Mo Azam, from the party’s left, off the shortlist in Oldham West when Labour MPs were worried for their own seats and about the Ukip effect if Labour selected a minority candidate. But that enraged the party’s minority politicians and led directly to the all-ethnic-minority shortlist in Manchester Gorton.

They also point out that the party's councillor base, from where many candidates are drawn, is still largely Corbynsceptic, though they hope that this will change in the next round of local government selections. (Councillors must go through a reselection process at every election.)

But the biggest shift has very little to do with the Labour leadership. The big victories for the Labour left in internal battles under Ed Miliband were the result of Unite and the GMB working together. Now they are, for various reasons, at odds and the GMB has proven significantly better at working shortlists and campaigning for its members to become MPs.  That helps Corbynsceptics. “The reason why so many of the unions supported Jeremy the first time,” one senior Corbynite argues, “Is they wanted to move the Labour party a little bit to the left. They didn’t want a socialist transformation of the Labour party. And actually if you look at the people getting selected they are not Corbynites, but they are not Blairites either, and that’s what the unions wanted.”

Regardless of why, it means that, two years into Corbyn’s leadership, the Labour left finds itself smaller in parliament than it was at the beginning.  

Stephen Bush is special correspondent at the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to British politics.