Robert Hanks: The Cycling Column

Jonny Trunk, presenter of OST, the excellent film music show on London's Resonance FM, reckons I should devote a column to "the small-wheel revolution", his theory being that the small-wheeled bicycle is taking over.

It's certainly true that there has been a surge in the number of small-wheelers in the past couple of years, at least in our corner of London. The ubiquitous Brompton accounts for a large slice of the increase, but other folders - Dahon, Birdy, Mezzo - are popular; and we've had a flurry of ancient shoppers, like the Raleigh Twenty and Sixties-vintage Moultons. Trunk, on his nippy 40-something Moulton Mini, is in the thick of the trend.

Most people who buy small-wheel bikes - SWBs - are attracted, I'd guess, by the look of the thing, the upright riding position, and the fact that they take up rather less room than a racer. Devotees also argue, following Sir Alec Moulton, inventor of the Moulton bike, that a smaller wheel has inherent physical advantages. The softer and springier a wheel, the harder it is to ride.

Small wheels, with their shorter spokes, are naturally stiff. What's more, the area of the tyre that makes contact with the road is smaller - a circular patch of rubber rather than an ellipse - which reduces rolling resistance, one of the main things that slows a bike down if you stop pedalling. The aerodynamic profile is smaller, making for less drag; and the rotating mass of the wheels is much smaller. All these things together mean that you can accelerate faster on a SWB.

You have to have the right sort of wheels and tyres. Leafing through a 15-year-old copy of Richard's Bicycle Book, I find that in the brief section on SWBs the great Ballantine was almost violently dismissive of the nasty little things, with their horrid fat tyres and heavy frames making them a pig to move.

And as if that wasn't bad enough, try stopping one, what with the slippery steel rims and flimsy calliper brakes. His complaints weren't unfounded: historically, SWBs had fat, soft tyres to compensate for the stiffness of the wheels, and stop the ride becoming unbearably bumpy; and because their design was not as strong as the traditional diamond-frame, they tended to be made of thick steel tubing that weighed a ton.

But that was then. I don't think any of Richard's strictures apply to the SWBs currently on the market, and Moultons have always been above that sort of thing. Sir Alec's design philosophy is based on using high-pressure tyres for the handling and acceleration, and making up for it with rubber suspension. I had a quick go on Trunk's Moulton Mini, and was shocked at how soft and yielding it was.

Even the sloppy old Raleigh Twenty, which was guilty of every crime Richard complained about, can be souped into a groovy little monster with the addition of alloy wheels and maybe a suspension seat post. Sheldon Brown has led the way on this - see www.sheldonbrown.com/raleigh-twenty.html - but a Google of "Raleigh Twenty" will lead you to dozens of pictures of gorgeous customised bikes.

For me, this goes under the heading of Things I Wish I'd Known When I Was 10, and all my mates had Choppers or proper racers. My Raleigh Stowaway three-speed was a source of deep shame. Now, it would be the coolest ride in town.

Against all the advantages of the SWB, though, I'd have to put a couple of big disadvantages: on our potholed roads, the small wheels can be overwhelmed by cracks. And while they may accelerate well over short stretches, over any sort of distance a traditional road bike just feels more comfortable and secure. I plan to carry on living large.