One Less Car: why drivers should love cyclists

Travel time considerations by car or by bike

One of the reasons some motorists abuse cyclists is because bicycles are generally assumed to be slow (except by the Daily Mail which says cyclists are speed-crazed demons) and so shouldn’t be taking up road space, road space paid for by motorists. Now, this site is all about how roads are NOT paid for by motorists, but by all taxpayers. Road tax doesn’t exist: it was abolished in 1937.

But let’s get back to road space. Instead of hating on cyclists, motorists should be showering us with love. Why? For every car not driven, that’s a huge piece of real estate taken out of the road space equation.

Economists measure this is in Passenger Car Equivalents. PCEs indicate the traffic impacts of larger vehicles compared with a typical car.

Larger and heavier vehicles cause more congestion than smaller, lighter vehicles because they require more road space and are slower to accelerate. Large trucks and buses tend to have 1.5-2.5 PCEs, depending on roadway conditions. Buses may carry loads of passengers but, from a driver’s perspective, they have a waddling PCE of 4.4. A people carrier imposes 1.4 PCEs, and a van 1.3 PCEs.

Bicycles, on the other hand, have svelte PCEs of 0.28. Cyclists can speedily flit in and out of traffic like ‘bike salmon’, as BikeSnobNYC puts it, and cause next to no congestion ripple effects.

‘Transportation Cost and Benefit Analysis II – Congestion Costs 2009’ from the Victoria Transport Policy Institute Australia includes this table from transport academic Todd Litman (author of Whose Roads?):


It summarises congestion factors for bicycles. The authors conclude that “Bicyclists probably contribute relatively little congestion overall…”

“Compact and electric cars, vans, light trucks and motorcycles impose about the same congestion costs as an average car. Rideshare passengers cause no incremental congestion. Buses and trolleys are considered to impose twice, and bicycles 5 percent the congestion of an average car.”
Todd Litman, ‘Bicycling and Transportation Demand Management’: Transportation Research Record 1441, 1994

So, if a bicycle causes just 5 percent the congestion of an average car it would take a large peloton of riders to cause gridlock. Just such a peloton is formed at Critical Mass protest rides. But a Critical Mass ride isn’t static: far from it. It ambles along at about 8mph or more, and is quickly somewhere else. Critical Mass tends to be last-Friday-of-the-month-monthly; car-caused congestion is daily and endemic.

Another peloton, of course, is the bunch of road bike riders out for a spin, normally at the weekend. But these are recreational riders, aiming for country lanes. Daily commuter cyclists – the sort drivers will see in towns and cities each day – are solo riders, they never hunt in packs. Not that there’s anything genuinely congestion-forming by a big bunch of road riders. For a start, they’ll be going fast, 20-25mph or more. When a bunch deems that conditions are safe to overtake it, riders invariably string out: there’s no benefit to having an impatient car trailing the pack.

Sadly, many motorists wish to be going fast for every millisecond. Commissioner Kevin Weir of the Isle of Man, for instance. In a proposal to register all bicycles on ‘Mark Cavendish Island’, Mr Weir said roadies “ride four in a row, they will not drop behind, a motorist gets annoyed and overtakes in a bad spot, they have an accident and the cyclists race on.”

Come again? The motorist overtakes in a bad spot and it’s the fault of the cyclists? Mr Weir’s ideas – including compulsory hi-vis jacket wearing – look likely to be adopted by the Isle of Man, leading to a rush of comments to the local newspaper. Cyclist Andrew Roche said:

“If I’m driving and come across a slow moving vehicle like a road sweeper, or hedge cutter, or even a horse I don’t get in a rage and start blaring the horn, I just wait and pass it when it’s safe. Why? Because it’s not a major issue. I might have added 30 seconds to a minute onto my journey. If someone can’t wait that long to get past a group of cyclists who are riding sensibly, then maybe they should seek anger management.”

The time-enemy of drivers isn’t cyclists, it’s other drivers. Getting more folks out of cars and on to bikes would be a good thing for those motorists who refuse to have anything other than a windshield view of the world.