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Stop expanding the ULEZ to all the London boroughs in 2023

Old but still relevant. Khan is full of s***

A few points re motorcycle NOx emissions.
NOx output is at its worst when the engine is working hard. That can't be for long on a motorcycle in city setting but will be significant for a heavy car.
Two-strokes are inherently low NOx emitters due to operating at lower pressures (twice as many power strokes mean each stroke can be less stressed) and built in EGR courtesy of less than 100% scavenging.
Two-stroke particulates aren't as problematic as diesel particulates. The problem with particulates is less with the particulates and more with what attaches to them - some pretty nasty chemicals in the case of diesels. Two-stroke particulates could be reduced but at the price point of the vehicles in question, no one bothered.
 
A few points re motorcycle NOx emissions.
NOx output is at its worst when the engine is working hard. That can't be for long on a motorcycle in city setting but will be significant for a heavy car.
Two-strokes are inherently low NOx emitters due to operating at lower pressures (twice as many power strokes mean each stroke can be less stressed) and built in EGR courtesy of less than 100% scavenging.
Two-stroke particulates aren't as problematic as diesel particulates. The problem with particulates is less with the particulates and more with what attaches to them - some pretty nasty chemicals in the case of diesels. Two-stroke particulates could be reduced but at the price point of the vehicles in question, no one bothered.
I thought 2 stroke engines were bad for health and the environment.
 
I thought 2 stroke engines were bad for health and the environment.
Not necessarily so but the cheapest carburetted ones tend to throw a lot of unburned fuel out their exhausts without troubling it with combustion and that isn't ideal for health. Doesn't have to be that way though as a competent system of direct injection of fuel into the cylinder can circumvent that.
The NOx and particulates are as already mentioned.
 
Not necessarily so but the cheapest carburetted ones tend to throw a lot of unburned fuel out their exhausts without troubling it with combustion and that isn't ideal for health. Doesn't have to be that way though as a competent system of direct injection of fuel into the cylinder can circumvent that.
The NOx and particulates are as already mentioned.
Old but I suppose we don’t use them so much any more 4AD8F2B5-FF4F-4DD5-B44F-1B221C8C4157.jpeg
 
Old but I suppose we don’t use them so much any more View attachment 141256
Carburetted emitting high levels of UBHC (un-burned hydrocarbon). 2T at its worst - built to a price. Newer carburetted engines employing stratified charge are better but direct injection (in a better format than currently exists) is required to eliminate the last of UBHC.
The 4T engine has over 100+ years had £billions spent on it in development - the 2T a fraction of that. Yet, the only engine (without hybrid technology so rule out F1) to get close to 50% thermal efficiency is a 2T. Find it powering the largest of ocean going ships.
 
Carburetted emitting high levels of UBHC (un-burned hydrocarbon). 2T at its worst - built to a price. Newer carburetted engines employing stratified charge are better but direct injection (in a better format than currently exists) is required to eliminate the last of UBHC.
The 4T engine has over 100+ years had £billions spent on it in development - the 2T a fraction of that. Yet, the only engine (without hybrid technology so rule out F1) to get close to 50% thermal efficiency is a 2T. Find it powering the largest of ocean going ships.
So basically any reasoning behind polluting engines or not can be pulled apart by a few minutes on the internet.

I didn’t know that ocean going ships had 2 stroke engines. 👍
 
What makes me larf is Khan claims 90% of cars are ULEZ compliant within London and the planned expansion of the ULEZ zone.. So does that mean the 10% that are not compliant have prompted the government to invest millions of pounds in infrastructure to charge them for polluting the air. 10% of the cars are causing all these respiratory problems and deaths we hear about.. 10%!!! wow they must be really bad.... Those 10% must be causing a smog of biblical proportions..

I would charge them way more than £12.50 a day!!


They find the money to do this, yet they cant find the money to install public chargers for zero emission EV cars etc?? Somehow I think we are being sold a pup here..
 
So basically any reasoning behind polluting engines or not can be pulled apart by a few minutes on the internet.
The engine that would have replaced the Rolls-Royce Merlin was a 2T (Crecy). The aero engine with unparalleled fuel efficiency (Nomad) was a 2T. But the jet engine arrived and was a better fit for aviation. They can be the most powerful (400hp/litre NA) or the most frugal - and anything in between - but mainly neglected.
I didn’t know that ocean going ships had 2 stroke engines. 👍
The one domain where they were taken seriously and that was immune to the politics that saw it killed off elsewhere in favour of engines that were much costlier to build. Back in the 1960s it was said that the 2T will have to be revisited when ''NOx emissions become problematic''. Which is where we are now.
 
What makes me larf is Khan claims 90% of cars are ULEZ compliant within London and the planned expansion of the ULEZ zone.. So does that mean the 10% that are not compliant have prompted the government to invest millions of pounds in infrastructure to charge them for polluting the air. 10% of the cars are causing all these respiratory problems and deaths we hear about.. 10%!!! wow they must be really bad.... Those 10% must be causing a smog of biblical proportions..

I would charge them way more than £12.50 a day!!


They find the money to do this, yet they cant find the money to install public chargers for zero emission EV cars etc?? Somehow I think we are being sold a pup here..
I wonder if the 10% are black cabs?
 
What makes me larf is Khan claims 90% of cars are ULEZ compliant within London and the planned expansion of the ULEZ zone.. So does that mean the 10% that are not compliant have prompted the government to invest millions of pounds in infrastructure to charge them for polluting the air. 10% of the cars are causing all these respiratory problems and deaths we hear about.. 10%!!! wow they must be really bad.... Those 10% must be causing a smog of biblical proportions..

I would charge them way more than £12.50 a day!!


They find the money to do this, yet they cant find the money to install public chargers for zero emission EV cars etc?? Somehow I think we are being sold a pup here..

I don't think you are reading this correctly.

The comment was made in reference to cars entering the zone, not cars registered to owners living inside the zone - the two are very different.

In terms of ownership, I would hazerd a guess that ULEZ compliance for cars owned by people living inside the zone is much higher than 90%, and for people living outside the zone it is much lower.

The claimed achievement here is that the ULEZ charge successfully deters people from driving older Diesel cars into the zone.

I would hazerd another guess that the 10% of non-compliant cars that drive into zone comprise chiefly from cars owned by people who do not live inside the zone.

So ULEZ does work in that it (a) got most Londoners living inside the zone to replace their non-compliant cars with compliant ones, and (b) it deters people living outside the zone from driving their non-compliant card into the zone.
 
So ULEZ does work in that it (a) got most Londoners living inside the zone to replace their non-compliant cars with compliant ones, and (b) it deters people living outside the zone from driving their non-compliant card into the zone.
Of course the ULEZ will work but that’s not the argument here.
 
I don't think you are reading this correctly.

The comment was made in reference to cars entering the zone, not cars registered to owners living inside the zone - the two are very different.

In terms of ownership, I would hazerd a guess that ULEZ compliance for cars owned by people living inside the zone is much higher than 90%, and for people living outside the zone it is much lower.

The claimed achievement here is that the ULEZ charge successfully deters people from driving older Diesel cars into the zone.

I would hazerd another guess that the 10% of non-compliant cars that drive into zone comprise chiefly from cars owned by people who do not live inside the zone.

So ULEZ does work in that it (a) got most Londoners living inside the zone to replace their non-compliant cars with compliant ones, and (b) it deters people living outside the zone from driving their non-compliant card into the zone.

10% of cars within or 10% of cars entering or however you split it is still 10%? ie a small amount.

If the aim is to reduce air pollution because of this 10% of cars, then simply ban them from the zone, don't charge people. But I find it hard to believe the aim is to actually reduce air pollution..

After all, there are bigger issues than that affecting people lives..
 
10% of cars within or 10% of cars entering or however you split it is still 10%? ie a small amount.

If the aim is to reduce air pollution because of this 10% of cars, then simply ban them from the zone, don't charge people. But I find it hard to believe the aim is to actually reduce air pollution..

After all, there are bigger issues than that affecting people lives..

Why ban?

At current, only 10% of cars entering the Zone are non-compliant.

This means that the ULEZ charge is an effective deterrent, because non-compliant cars avoid the zone (and the charge).

A complete ban will also eliminate the remaining 10%, agreed. But you could equally argue that since only a very smal number of non-compliant cars now enter the zone, NOx levels are low and there's no need for any further measures.
 
6 of my neighbours have now had to get shot of their 13, 14 and 15 plate diesels for a crappy price and purchase newer diesel vehicles thus shelling out money they can’t really afford.

They’re not very happy.
 
This means that the ULEZ charge is an effective deterrent, because non-compliant cars avoid the zone (and the charge).


So, Kahn has effectively forced them to give up their vehicles but what’s he given them in return?

What are the workers going to use to get to work?
 

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