[sustran] motorcycles and congestion

[Harun Al Rasyid Sorah Lubis]

I want to answer the basic question that Walter raised
in the beginning.

There is a PhD thesis of Heru Sutomo, Leeds, Institute for
Transport Studies, 1992 concerning this.

He gathered data from several cities in Indonesia.Bandung,
Yogyakarta, Jakarta, Semarang

Then create a micro-simulation model (car-following),
by treating the lane width in meter
by meter, even cm by cm, if you like, to allow small size vehicle
manuevering where space available between vehicles, all vehi
cles are approaching a signalised junction.

Other decision variables he considered is the proportion of m/c
and other variety of non-motor vehicles, such as trishaw, bike,
also including the motor vehicles, private car to heavy and trailer.

Using regression technique in determining the pcu value, average
estimate in all conditions simulated, he came up with:
0.27 (0.02) for m/c, read  pcu (standard error)
0.19 (0.08) for bike
0.89 (0.06) for trishaw
1.53 (0.11) for medium veh.
2.33 (0.14) heavy veh,
2.98(0.29) trailers.

Certainly, there are many other reseachers already look at
this particular issue since Holroyd (1963), Webster (1966) most in UK
and Djohar(1984) in Bandung.  They came up with pcu for m/c in the
range of 0.2 - 0.53

I can tell you what Indonesia did concerning policy on m/c, where 70%
at least registered from the total motor vehicle statistics nationally,
mostly Japanese made.

Compulsory helmet was put in place since 1984. Unlike in Taipei,
here we havenot got exclussive lane for m/c, also not yet for bike.

In inter-uban road, it is suggested for m/c to switch  the front light on.

Reasons for owning m/c basically, this is the only choice the below middle
income people could afford before owning car, rather to experience more
'costly'
public transport, especially in the big cities, where public transport is
totally
hopeless. More m/c riders will switch to private car, once their income
makes
that possible, though it is very unreasonable for them to have it  in terms
of income
class.  People at that marginality, thought it is a 'must' to have a private
car of whatever
age than to experience transport 'cost' more, where in average 35%-40%
income is
allocated to transport, according to a specific survey in Yogyakarta, could
be more
in Jakarta, maybe...

During the prolonged Asia economic flu,  I would reckon rate of increase in
m/c
ownership will rise, certainly down for private car, no evidence yet
available for m/c.

I can tell you, no single road users sofar complaint with such proportion
of m/c we have here, in road capacity terms. If there is,
I could guess it is due to the noisy,  if in case the youth m/c riders
designed that on purpose, but this very few. They do complaint sometimes
if the m/c moves above the normal speed limit, again this is very few.

Finally, m/c are used for 'non-conventional' public transport,
'ojeg' we call it, in the area where conventional ones do not exist.


Harun al-Rasyid S. Lubis
Traffic Laboratory
Department of Civil Engineering
INSTITUT TEKNOLOGI BANDUNG

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