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Motorcycles and Climate Change January 05 2007

Those of you who know me (and those who have looked at our family's green roof garage or come across the book Manspace) know that I am an ardent advocate of motorcycles as transportation. I recently came across a UK study that validates my intuition with respect to motorcycles and climate change.

An except:

In so far as climate change is a consideration, motorcycles have a clear
advantage over passenger cars. The maximum emissions of CO2 from motorcycles
recorded in recent tests, fall below the average values recorded from the
passenger car fleet. This is true for petrol engined passenger cars that
dominate the UK fleet and also the diesel fleet that exists on the basis of
its fuel economy. If one considers lower capacity motorcycles which dominate
the urban/commuter sector, their CO2 emissions tend to be less than half
those of the average passenger car.
 
When considering gaseous pollutants it is apparent that the nature of the
test cycle used during emissions measurement can have a significant
influence on the results obtained. For the purposes of comparison this paper
has considered the emission of two pollutants (NOx and HC) measured over
“real world” test cycles that have recently been developed for both
passenger cars
and for motorcycles. Comparison of these results has been put in context by
reference to the emission limits set out in legislation for passenger cars.
 
Lower legislated limits for passenger cars would suggest that the
environmental performance of passenger cars would be better than
motorcycles. The available data suggests that this is the case, although the
margin of difference is not as great as the difference in legislated limit
values would suggest. Average emissions of NOx and HC from motorcycles is
approximately one Euro standard behind that from petrol fuelled passenger
cars. However, the NOx performance from motorcycles is generally better than
that from diesel fuelled cars that are increasing in popularity because of
their fuel efficiency.
 
Future emission standards have been agreed for motorcycles and these are
almost certain to cause the use of carburettors (a major cause of high HC
emission) to cease. It is also expected that catalyst technology will be far
more widespread in the motorcycle fleet providing further improved emission
control. In addition, the complexity of the test cycle over which future
motorcycle emissions will be measured should reduce the possibility for
disparity between regulated and “real world” emissions.

Read a detailed abstract of the study here: <http://www.bmf.co.uk/briefing/Bikes-Go-Greener.html>

-RH