EEEEEEKK 16-times more pollution!

[Jiminy]

That is NOT a paper, it is a report on a paper. There is a huge difference.

VERY wise comment. Some people here seem to have forgotten it.

One thing we can comment on though is a simple matter of logic: Each litre of fuel has the same chemical composition, and whether it is burnt in a car or a bike engine it will put out a similar level of exhaust emmisions. The exact composition of these emmisions will vary depending of the burn efficiency, catalytic convertor effectiveness etc. However the only true measure of pollutants is the amount of fuel burnt per distance travelled.

Hum, if I remember well my school years (very long ago, and my memory is not that great anymore :-)), the same chemical constituents can be recomposed in different ways, not all of them having the same positive or negative impact. It seems plausible that the polluting emissions from a given engine might be worse than from another engine using the same fuel.

Just a few comments after reading the article.

eight different motorbikes with those of 17 cars

That's not a lot to draw meaningful statistics from...

up to sixteen times more of these pollutants

Typical journalist quote (or is it the author?). Probably means that the oldest and worst motorbike in the worst sample was about 16 times worse than the best car in the best sample. Read again slowly ;-). As to where the average was...

And this was during the

urban test cycle

, probably meaning (my guess) cold engine running idle for a short period of time. I don't think that motorcycles (especially scooters?) are very efficient at that, which is one of the interesting points of the article.

This is not a study in situation, but a laboratory conclusion. Again, it does NOT say that Joe Motorcyclist pollutes more than Joe Cager, but draws attention to the fact (my reading) that little has been done to make motorbikes reduce their emissions of pollutants in the recent years compare to cars, which I find hard to deny (e.g. catalytic converters), and Joe Motorcyclist could pollute even much less than today!

I haven't read the full study, but I find that the abstract goes that way, see for yourself: http://www.ncbi.nlm.nih.gov/sites/en...indexed=google

And just to add another bit to the discussion:
http://www.empa.ch/plugin/template/empa/*/39486/---/l=2

My two cents...

[smoky]

Baaaa
Nation/ World is full of Sheep.

That was my point – I was being sardonically satirical

[smoky]

... the same chemical constituents ..recomposed in different ways, ..same positive or negative impact. It seems plausible....
.....means that the oldest and worst motorbike in the worst sample was about 16 times worse than the best car in the best sample.... cold engine running idle for a short period of time. ...This is not a study in situation, but a laboratory conclusion. Again, it does NOT say that Joe Motorcyclist pollutes more than Joe Cager,...that little has been done to make motorbikes reduce their emissions of pollutants in the recent years ...

Now look here you – don’t go interrupting a good thread with facts, it’s KB!

[huck farley]

This is because greenies think fun = bad.

I agree with your comments re the Greene's, and tree hugger have stepped over the line and are getting to much attention re their policies on pollution. I read an article a while ago whereas in China a small city of 8.5 million people lost the vote to continue riding scooters and small bore motorcycles as the Chinese Greeies put up a better argument than the two wheeler road users.

As a result over 1.5million bikes were ordered of the road and went to the scrap yards (probably to help make another warship!!) The two wheel riders complied with the order, and turned their machines in over a 4 week period. Being a communist country I shudder to think what would have happend if the residents took no notice and continued to ride their two wheelers to work.

[huck farley]

Way OT but how about this for a semi-wind-powered cargo ship:

http://www.engadget.com/2007/12/19/k...il-in-january/

Great Idea. But I would love to see them launch and also retrieve this massive thing.

[Jantar]

...Hum, if I remember well my school years (very long ago, and my memory is not that great anymore :-)), the same chemical constituents can be recomposed in different ways, not all of them having the same positive or negative impact. It seems plausible that the polluting emissions from a given engine might be worse than from another engine using the same fuel....

True, but the article talks about the quantity of pollutant, not the quality. Note the part

16-times more pollutant

.

Petrol burns to give off mainly CO, CO2, H2O, and a very small quanity of other exhaust chemicals such as NO, NO2, SO2 etc. There is a tiny amount of other emmisiions, and that is why many modern vehicles have catalytic convertors. So to get a measure of the quanity of pollutants, all that is need is to know the amount of fuel burnt.