We know that motorcycles get far better gas mileage than passenger cars and trucks, so it follows that if motorcycles replaced cars on the roads, gas consumption would decrease. But traffic would also drop significantly -- a revelation that comes courtesy of a new study by a Belgian transportation-research
Researchers used computer-modeling software to analyze a stretch of highway between the Belgian cities of Leuven and Brussels, pulling from rush-hour traffic statistics during a typical workday last May. They found that if 10 percent of cars were replaced by motorcycles, drivers' commuting times would decrease by 40 percent and emissions would drop by 6 percent. (The latter is a combination of the fact that motorcycles inherently have lower emissions and that emission rates drop as a vehicle's speed increases -- which it is wont to do when traffic lightens or dissipates.)
Moreover, when the results were extrapolated to Belgium's other highways, the time savings for all vehicles was 15,000 hours per day. And when 25 percent of cars were swapped out for motorcycles, traffic was eliminated entirely.
The explanation for the traffic cure is simple enough. "When there is little traffic on the road, it can be expected that motorcycles will take up as much space on the road as cars," researchers wrote. "However, when the road becomes busier, and the speed of the traffic flow falls, motorcycles take up less space. Some motorcycles keep less distance from the vehicle in front or ride between two lanes." And when car traffic stops altogether, motorcycles keep moving thanks to lane splitting -- the practice of steering between rows of cars lined up in traffic lanes, which is legal in many parts of the world.
Since the study incorporated only statistics on Belgium's primary roads, its main commuter thoroughfares, there are limits to what researchers can do to predict further-reaching traffic reductions. But they speculate that secondary roads would experience a similar traffic boon: "Based on a number of partial reflections, it can be expected that the time benefit is of the same order of magnitude as that of the primary road network," they wrote, though they added that "additional research is needed to substantiate this statement."