On September 20, London’s transport authorities turned some city streets over to bicycles, providing a striking illustration of the range of means to convert pedalling into motion.
Some participants in the event, similar to car-free festivals held in many cities worldwide, were reclining; others used suspension bikes that could have surmounted rocks; some were on pared-down machines with only a frame, handlebars, wheels, pedals and a chain.
The range of bike technology on offer has been a significant factor, many believe, in reviving cycling in many large cities – including New York, Amsterdam and Copenhagen, as well as London – even as it declines elsewhere in the developed world. Cyclists now have a dazzling choice of ways of controlling their machines, connecting themselves to the pedals and frame materials. There are bikes that hardly ever suffer punctures, whose brakes stop them quickly and safely and whose gears change easily and predictably.
Progress has been so rapid it has even created a backlash, with some young, fashionable cyclists reverting to far simpler machines. However, Tom Bogdanowicz, campaigns director for the London Cycling Campaign, applauds how the improvements have made cycling possible for people who once found the gears and brakes too cumbersome.
“It was a chore,” he says. “Now anyone can change gears on a bike. Anyone can get fairly good braking.”
The main mechanism driving most bicycles remains a set of pedals and a chain connected via a gearing mechanism to the rear wheel.
The most popular gear arrangement remains the derailleur system, developed in the 1920s and 1930s for racing. The system – one of mankind’s simplest but most effective mechanical inventions – uses a cable to pull a mechanism in and out beneath cog wheels – known as sprockets – attached to the bike’s rear axle. The mechanism’s movements derail the chain from one sprocket to another, changing the number of wheel turns for each pedal revolution.
Many bikes have another derailleur mechanism to switch the chain between different-sized cogs – known as chainrings – attached to the pedals. Switches between chainrings give a wider range of gear settings.
Recent years have seen innumerable improvements. Sprockets are now shaped to let the chain move smoothly and easily. While gear levers 20 years ago often required riders to use a lever between their legs, most now click easily between gears and are mounted on handlebars. The number of gears is constantly increasing, as ever-thinner chains allow more sprockets to be crammed between the wheel and frame.
Mark Reilly, designer for Enigma Bikes, a high-end bicycle company based in East Sussex, England, says the sophisticated, thin chains for bikes with 11 sprockets need to be assembled with sophisticated tools that alone cost around £150.
“It’s got to be perfect,” he says of the fitting of such chains. “It’s not going to be user-serviceable any more. It’s going to be like cars.”
The latest innovation, Mr Reilly says, is electronically-operated gears, where the gear changer signals electrically to a small motor to change gears. That technology – currently costing thousands of euros – will soon become mainstream, he predicts.
Other once-obscure technologies have made similar transitions into the mainstream. High-street bike shops now sell models with light, flexible carbon-fibre forks once restricted to top-level racing. Hydraulic disc brakes similar to those on cars are a common site on commuter bikes as well as the top-level mountain bikes for which they were invented.
However, recent years’ key trend among cyclists has been to rebel against the growing sophistication and revert to bikes sometimes lacking such apparent essentials as brakes. The fixed-wheel bikes popular with cycle couriers in New York, London and some other cities are unable to freewheel and can be stopped if the rider pushes backward on the pedals to slow the bike down.
Dominic Mason, designer for UK-based Kinesis Bikes, says the popularity of fixed-wheel bikes has made customers re-examine whether they want to buy slick-looking bikes mainly geared towards speed and performance.
Referring to two of the world’s biggest bike brands, he says: “It’s made them think, ‘I can have something different’ and made them think, ‘I don’t necessarily want to be on a Trek or a Specialized’.”
Yet, at this year’s Cycle Show 2009 in London, one of Europe’s biggest trade fairs, there were signs that the hardy derailleur gear was fighting back. The number of fashionable, fixed-wheel bikes remained striking – to the puzzlement of some bike designers.
But the stands of many niche designers of very simple bikes featured fashionably retro-styled machines set up with gears and brakes for road-racing and, especially, Cyclocross racing.
Mr Mason sees an affinity between riders used to sprinting round cities on bikes with no brakes and Cyclocross, a challenging sport involving racing on grass tracks over hills and obstacles. It also happens that Cyclocross bikes offer riders the convenience of benefiting from cycling technology that briefly looked as if it might go out of fashion.
“It’s a hard-core niche sport,” Mr Mason says. “Fixie riders identify with the Cyclocross riders. It’s perfect for a commuter too. It has big clearances [between the frame and ground] and you can put a rack on some of them and mudguards.”