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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Owen Smith promises to be a "cold-eyed revolutionary" - but tiptoes round Brexit

The Labour leader challenger takes Jeremy Corbyn on at his own anti-austerity game. 

Owen Smith may be challenging Jeremy Corbyn for the Labour leadership but it seems he has learnt a thing or two from his former boss. 

One year on from abstaining from the Tory Welfare Bill - a decision he now says he regrets - Smith attacked the former Chancellor George Osborne’s austerity policies from Orgreave, a former steel plant which was pivotal during the miners’ strike.  

Listing frustrations from library cuts to delayed trains, Smith declared: “Behind all of these frustrations is one cause – austerity.”

Borrowing the rhetoric that served Corbyn so well, he banged the drum about pay, labour rights and fair taxes. 

Indeed, a spokesman from Jeremy for Labour popped up to say as much: “We welcome Owen’s focus on equality of outcome, reindustrialisation and workers' rights - and his support for policies announced in recent months by Jeremy Corbyn and John McDonnell.”

On policy, though, Smith showed a touch of his own. 

His description of the Department for Work and Pensions as “a byword for cruelty and insecurity” resonates with the deep fear many benefit claimants feel for this faceless but all powerful authority. His promise to scrap it will not go unnoticed.

Another promise, to end the public sector pay freeze, is timely given widespread expectations that withdrawing from the EU’s single market will push up prices. 

He also appealed to the unions with a pledge to scrap the “vicious and vindictive” Trade Union Act. 

The policies may be Corbynite, but where Smith stands out is his determination to be specific and practical. He is selling himself as the Corbyn who actually gets things done. Asked about what he would replace zero-hours contracts with, he responded: "Well it could be one [hour]. But it can't be zero."

As he concluded his speech, he promised “revolution” but continued:

“Not some misty eyed romanticism about a revolution to overthrow capitalism.

“But a cold-eyed, practical, socialist revolution, through a radical Labour Government that puts in place the laws and the levers that can genuinely even things up.”

Smith’s speech, though, steered clear of grappling with the big issues of Brexit. He stands in favour of a second referendum on the Brexit deal, which may appease Labour's inner city voters but could frustrate others who voted Leave.

On the free movement of people – widely viewed as a dividing line between Labour’s Corbynite members and the wider voting population - he has been vague. He has previously expressed support for the "progressive case against freedom of movement" and criticised Corbyn for failing to understand patriotism. But this is not the same as drawing up policy. Whether he can come up with strong views on immigration and still appeal to both voter bases will be his biggest challenge of all. 

Owen Smith's 20 policies

1.      A pledge to focus on equality of outcome, not equality of opportunity 
2.      Scrapping the DWP and replacing it with a Ministry for Labour and a Department for Social Security
3.      Introducing modern wages councils for hotel, shop and care workers to strengthen terms and conditions
4.      Banning zero hour contracts
5.      Ending the public sector pay freeze
6.      Extending the right to information and consultation to cover all workplaces with more than 50 employees
7.      Ensuring workers’ representation on remuneration committees
8.      Repealing the Trade Union Act
9.      Increase spending on the NHS by 4 per cent in real-terms in every year of the next parliament
10.  Commit to bringing NHS funding up to the European average within the first term of a Labour Government
11.  Greater spending on schools and libraries
12.  Re-instate the 50p top rate of income tax
13.  Reverse the reductions in Corporation Tax due to take place over the next four years
14.  Reverse cuts to Inheritance Tax announced in the Summer Budget
15.  Reverse cuts to Capital Gains Tax announced in the Summer Budget
16.  Introduce a new wealth Tax on the top 1 per cent earners
17.  A British New Deal unveiling £200bn of investment over five years
18.  A commitment to invest tens of billions in the North of England, and to bring forward High Speed 3
19.  A pledge to build 300,000 homes in every year of the next parliament – 1.5 million over five years
20.  Ending the scandal of fuel poverty by investing in efficient energy