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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I believe only Yvette Cooper has the breadth of support to beat Jeremy Corbyn

All the recent polling suggests Andy Burnham is losing more votes than anyone else to Jeremy Corbyn, says Diana Johnson MP.

Tom Blenkinsop MP on the New Statesman website today says he is giving his second preference to Andy Burnham as he thinks that Andy has the best chance of beating Jeremy.

This is on the basis that if Yvette goes out first all her second preferences will swing behind Andy, whereas if Andy goes out first then his second preferences, due to the broad alliance he has created behind his campaign, will all or largely switch to the other male candidate, Jeremy.

Let's take a deep breath and try and think through what will be the effect of preferential voting in the Labour leadership.

First of all, it is very difficult to know how second preferences will switch. From my telephone canvassing there is some rather interesting voting going on, but I don't accept that Tom’s analysis is correct. I have certainly picked up growing support for Yvette in recent weeks.

In fact you can argue the reverse of Tom’s analysis is true – Andy has moved further away from the centre and, as a result, his pitch to those like Tom who are supporting Liz first is now narrower. As a result, Yvette is more likely to pick up those second preferences.

Stats from the Yvette For Labour team show Yvette picking up the majority of second preferences from all candidates – from the Progress wing supporting Liz to the softer left fans of Jeremy – and Andy's supporters too. Their figures show many undecideds opting for Yvette as their first preference, as well as others choosing to switch their first preference to Yvette from one of the other candidates. It's for this reason I still believe only Yvette has the breadth of support to beat Jeremy and then to go on to win in 2020.

It's interesting that Andy has not been willing to make it clear that second preferences should go to Yvette or Liz. Yvette has been very clear that she would encourage second preferences to be for Andy or Liz.

Having watched Andy on Sky's Murnaghan show this morning, he categorically states that Labour will not get beyond first base with the electorate at a general election if we are not economically credible and that fundamentally Jeremy's economic plans do not add up. So, I am unsure why Andy is so unwilling to be clear on second preferences.

All the recent polling suggests Andy is losing more votes than anyone else to Jeremy. He trails fourth in London – where a huge proportion of our electorate is based.

So I would urge Tom to reflect more widely on who is best placed to provide the strongest opposition to the Tories, appeal to the widest group of voters and reach out to the communities we need to win back. I believe that this has to be Yvette.

The Newsnight focus group a few days ago showed that Yvette is best placed to win back those former Labour voters we will need in 2020.

Labour will pay a massive price if we ignore this.

Diana Johnson is the Labour MP for Hull North.