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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Debunking Boris Johnson's claim that energy bills will be lower if we leave the EU

Why the Brexiteers' energy policy is less power to the people and more electric shock.

Boris Johnson and Michael Gove have promised that they will end VAT on domestic energy bills if the country votes to leave in the EU referendum. This would save Britain £2bn, or "over £60" per household, they claimed in The Sun this morning.

They are right that this is not something that could be done without leaving the Union. But is such a promise responsible? Might Brexit in fact cost us much more in increased energy bills than an end to VAT could ever hope to save? Quite probably.

Let’s do the maths...

In 2014, the latest year for which figures are available, the UK imported 46 per cent of our total energy supply. Over 20 other countries helped us keep our lights on, from Russian coal to Norwegian gas. And according to Energy Secretary Amber Rudd, this trend is only set to continue (regardless of the potential for domestic fracking), thanks to our declining reserves of North Sea gas and oil.


Click to enlarge.

The reliance on imports makes the UK highly vulnerable to fluctuations in the value of the pound: the lower its value, the more we have to pay for anything we import. This is a situation that could spell disaster in the case of a Brexit, with the Treasury estimating that a vote to leave could cause the pound to fall by 12 per cent.

So what does this mean for our energy bills? According to December’s figures from the Office of National Statistics, the average UK household spends £25.80 a week on gas, electricity and other fuels, which adds up to £35.7bn a year across the UK. And if roughly 45 per cent (£16.4bn) of that amount is based on imports, then a devaluation of the pound could cause their cost to rise 12 per cent – to £18.4bn.

This would represent a 5.6 per cent increase in our total spending on domestic energy, bringing the annual cost up to £37.7bn, and resulting in a £75 a year rise per average household. That’s £11 more than the Brexiteers have promised removing VAT would reduce bills by. 

This is a rough estimate – and adjustments would have to be made to account for the varying exchange rates of the countries we trade with, as well as the proportion of the energy imports that are allocated to domestic use – but it makes a start at holding Johnson and Gove’s latest figures to account.

Here are five other ways in which leaving the EU could risk soaring energy prices:

We would have less control over EU energy policy

A new report from Chatham House argues that the deeply integrated nature of the UK’s energy system means that we couldn’t simply switch-off the  relationship with the EU. “It would be neither possible nor desirable to ‘unplug’ the UK from Europe’s energy networks,” they argue. “A degree of continued adherence to EU market, environmental and governance rules would be inevitable.”

Exclusion from Europe’s Internal Energy Market could have a long-term negative impact

Secretary of State for Energy and Climate Change Amber Rudd said that a Brexit was likely to produce an “electric shock” for UK energy customers – with costs spiralling upwards “by at least half a billion pounds a year”. This claim was based on Vivid Economic’s report for the National Grid, which warned that if Britain was excluded from the IEM, the potential impact “could be up to £500m per year by the early 2020s”.

Brexit could make our energy supply less secure

Rudd has also stressed  the risks to energy security that a vote to Leave could entail. In a speech made last Thursday, she pointed her finger particularly in the direction of Vladamir Putin and his ability to bloc gas supplies to the UK: “As a bloc of 500 million people we have the power to force Putin’s hand. We can coordinate our response to a crisis.”

It could also choke investment into British energy infrastructure

£45bn was invested in Britain’s energy system from elsewhere in the EU in 2014. But the German industrial conglomerate Siemens, who makes hundreds of the turbines used the UK’s offshore windfarms, has warned that Brexit “could make the UK a less attractive place to do business”.

Petrol costs would also rise

The AA has warned that leaving the EU could cause petrol prices to rise by as much 19p a litre. That’s an extra £10 every time you fill up the family car. More cautious estimates, such as that from the RAC, still see pump prices rising by £2 per tank.

The EU is an invaluable ally in the fight against Climate Change

At a speech at a solar farm in Lincolnshire last Friday, Jeremy Corbyn argued that the need for co-orinated energy policy is now greater than ever “Climate change is one of the greatest fights of our generation and, at a time when the Government has scrapped funding for green projects, it is vital that we remain in the EU so we can keep accessing valuable funding streams to protect our environment.”

Corbyn’s statement builds upon those made by Green Party MEP, Keith Taylor, whose consultations with research groups have stressed the importance of maintaining the EU’s energy efficiency directive: “Outside the EU, the government’s zeal for deregulation will put a kibosh on the progress made on energy efficiency in Britain.”

India Bourke is the New Statesman's editorial assistant.