[sustran] motorcycles and congestion

[J.H. Crawford]

Todd Litman wrote:
>At 08:48 AM 7/15/98 +0100, J.H. Crawford wrote:
>>Todd Litman said:
>>
>>>My own conclusion is that the only legitmate social benefits of motorcycles
>>>are that they are somewhat more fuel efficient, and they are more
>>>affordable to purchase and thus provide mobility to some lower income
>>>people, but both of these benefits are slight. 
>>
>>I would take partial exception to this. In the developing nations,
>>small (+/- 70 cc) motorcycles are commonly the first transport upgrade
>>bought by families after they have a bicycle or two. These motorcycles move 
>>in  great swarms in the Asian capitals and have got to be much more space
>>efficient than cars. They almost always ride at least two abreast and
>>don't pay much attention to lane markings. They are, of course, noisy, 
>>and most of the machines of this class are 2-stroke, so the pollution they 
>>create is terrible. The picture is different in the developed nations and
>>accords with Todd Litman's description as far as I am aware.
>
>I agree that motorcycles impose less congestion at lower traffic speeds.
>Motorcycling allows lower income households to afford motorized transport.
>It is certainly a benefit to those households, but the social benefits are
>mixed. Pollution is certainly a problem. 

I wish I could get my hands on some statistics. You see all kinds of
numbers floating around about how bad 2-stroke engines are, but I 
don't have a really hard source of data.

>An even greater problem, in my
>opinion, is the accident costs, which are extreme in many developing
>countries. 

I'm sure it is.

>I suspect that to some degree high levels of motorcycling in
>developing countries represent a "social trap" (a situation in which
>individuals' benefits are in conflict with society's benefits), since once
>streets become crowded with motorcycles, conditions for pedestians,
>bicycles and public transit often suffer. It may be possible that total
>benefits would be greater from transport policies that encourage more
>public transit, bicycling and efficient land use solutions to
>transportation problems in developing countries.

I would certainly think so, yes. Unfortunately, many governments
in southeast Asia are busy banning human-powered solutions in
favor of the "modern" car.

>Passenger-Car Equivalents for Bicycles by Lane Width 
>
>				< 11 ft. Lane		11-14 ft.	> 14 ft.
>				-------------		---------	--------
>	Riding With Traffic		1.0		0.2		0.0
>	Riding Against Traffic	1.2		0.5		0.0

In Amsterdam, bikes ride both ways on almost all streets, and most
streets here are one way for cars. I suspect that the figures 
quoted above are only valid for high speeds--note that in narrow
lanes (and most streets here are much narrower than 11 feet),
a bike going against traffic is supposed to count as more than
one car. This does not accord with my observations here--the bikes
don't seem to slow down traffic much or cause a capacity reduction.

>4. Narrow, congested roads with moderate to high speed traffic.
>Bicycling on a narrow, congested road when the rider is unable to keep up
>with traffic can contribute to traffic congestion, depending on how
>difficult it is for faster vehicles to pass. 

Yes, it seems so.
 
>In summary, there is no evidence that bicycling increases overall traffic
>congestion, delay or accident risk (considering both increased and reduced
>congestion caused by bicycling), or that conflicts which develop between
>bicycles and motor vehicles can not be effectively resolved using existing
>laws and planning strategies.

I remember years ago seeing a film clip from Amsterdam, probably shot
during the early 50s. I don't know where it was, but it may have
been the Weteringcircuit, a traffic circle near here. It must have
been at rush hour, and there were simply hundreds upon hundreds of
bikes flowing smoothly around this circle. There are still a great
many bike commuters here, but not in numbers anything like what I
saw on that little flim clip. Love to know more about it if anybody
happens to know the source.



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J.H. Crawford    Crawford Systems    joel at xs4all.nl    http://www.carfree.com/