You would think so. Otherwise Alberto Contador would have tackled the mountains of Le Tour on an old school steel boneshaker rather than on a delicate wafer of carbon fibre so light it was at risk of floating away on the breeze. Otherwise, I wouldn’t have several featherweights of my own (each for a different occasion, you understand). So it was with some consternation that I read an article in the British Medical Journal in which a doctor reported that, on his daily commute of 27 miles, his brand new carbon steed was no quicker than an old, second hand steel bike weighing nearly 50% more.
It is a strange article, part of BMJ's Christmas in which somewhat light hearted articles about a variety of medical issues are published. These light hearted themes are still dressed up in the language of science, so one is never quite sure whether they are to be taken seriously or not. In this particular piece, an English GP, Dr Groves, describes his experiment about his daily cycle to work as a “single centre, randomised non-blinded trial; n=1. What this means in plain English is that he tossed a coin every morning to see which of his two bikes he should ride, that he made no attempt to prevent himself from knowing which of his bikes he was riding and that he didn’t involve any other riders in the trial. Now there are all sorts of things wrong with this. Trials are blinded for a reason. For example, I know I ride faster on my carbon bike simply because I put more effort in, embarrassed to be seen pootling around on what is so obviously a high end machine. There are also problems with a noisy dataset in this trial: if you remove the four most extreme times (outliers) then the result is reversed – the carbon bike comes out marginally faster.
However, whatever the failings in the design of the trial, there is no doubting that in real world conditions it is difficult to demonstrate a substantial advantage in riding a light bike. This is because, even on a hilly route through the Derbyshire dales, bike weight is only one factor that determines the transformation of rider power into forward momentum. For a start, bike weight is usually a fraction of that of its rider, both of which have to be dragged up those hills. And while weight is important, overcoming drag is also a major sink of expended energy, a fact that any rider who has cycled into a headwind can attest to.
Dr Groves concludes his article by suggesting that perhaps we should all save our money and stick to cheap steel bikes because they are just as fast. Does the man have no soul? Since when do issues of mere efficiency come into the choice of bike? Has he never felt the thrill of hefting a bike in one hand to find that it barely weighs anything at all? Has he never lusted after a bike just for its sheer aesthetic perfection? Has he never been tempted by the prospect of owning the same machine that was ridden to victory on one of the Grand Tours? It may well owe nothing to logic, it may well be a triumph of the seduction of marketing, but many bike purchases, especially those made by the infamous MAMILS, are driven by the desires of the heart and not the reasoning of the head.
In any case, if Dr Groves really is that worried about cycling efficiency he should work on his flexibility. A helpful mathematician from Montreal, writing on the BMJ website in response to Dr Groves’ article, has calculated that a 20% decrease in ‘frontal area’ would save Dr Groves 6 minutes and 36 seconds on his daily commute. Time to stretch that lower back, old boy and ride in those drops. ‘Tis what the pros do, after all.
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