It's Official

Qui bono? The manufacturers of catalytic converters, Johnson Matthey for
instance.

 

IANALBIASLAITYFT "cui bono", not "qui bono".

 

Probably.

 

Anything over 1500kg DIN kerb weight governed to 55mph max.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, platypus

<looks at BlingMobile>

Oi! Fekkorf.

--
Wicked Uncle Nigel - Podium Placed Ducati Race Engineer As featured in
Performance Bikes

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
SBS#39 OMF#6 Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
Suzuki TS250 "The Africa Single" Yamaha Vmax Honda ST1100 wiv trailer

 

It goes over 55?

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, platypus

Oh yes. Quite considerably.

There's a modicum of screaming involved, and I seem to be followed by an
air ambulance whenever I attempt it, but it really, really does.

--
Wicked Uncle Nigel - Podium Placed Ducati Race Engineer As featured in
Performance Bikes

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
SBS#39 OMF#6 Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
Suzuki TS250 "The Africa Single" Yamaha Vmax Honda ST1100 wiv trailer

 

Some days I can't see the mountains that are only 10 miles away due to
the smog.

 

muddy cat says...

Move to a less pikey area

 

I'm saving up so I can move next door to darsy.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, muddy cat

<drafts letter to Home Office>

Fucking foreigners, coming over here, forming ghettos.

--
Wicked Uncle Nigel - Podium Placed Ducati Race Engineer As featured in
Performance Bikes

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
SBS#39 OMF#6 Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
Suzuki TS250 "The Africa Single" Yamaha Vmax Honda ST1100 wiv trailer

 

Jesus Fucking Christ, you don't have post some shite.

 

Stop smoking and open your windows.

 

<drafts letter to Homeland Defense Department>

Fucking foreigners, coming over here, riding harleys.

 

No windows on the bike.

 

cwt?

 

It might be more accurate to say that the reduction of NOx in the cat
requires an oxygen-defficient input stream. Which effectively means that
the stream must have a surplus of unburned hydrocarbons. Which will be the
case when the engine is burning a stoichiometric mixture (or richer).


If the cat *didn't* require such an input, then why is it so important for
fuel-injection systems to maintain the mixture so close to stoichiometric?
If it were possible for the cat to function with much leaner, or much richer
exhaust, then why bother going to all the trouble to design such precise
fuel-metering systems? The requirement to keep the mixture so precisely
centred on stoichiometric is the primary reason that fuel-injection has
become so ubiquitous.


A lean-running engine will typically produce higher NOx levels than a
rich-running engine. Consider what happens when the cat is fed the
exhaust from a lean-running engine. The NOx levels remain high. The cat
does nothing to reduce them.


A rich-burning engine produces lower NOx levels, but higher levels of CO and
unburned HCs. Again, the cat does nothing to reduce them.


It's only at that "sweet-spot", when the engine is running on a
stoichiometric mixture, that the cat works efficiently. The fuel mixture is
kept "wobbling" slightly around that sweet-spot by a feedback loop, with an
oxygen-sensor in the raw exhaust stream measuring how much free oxygen there
is. If there's too much oxygen, the engine must be running lean, so the
system tells the injectors to remain open a little bit longer. If there's
not enough oxygen, the system instructs the injectors to shut off sooner.


What does running lean actually do to the cat? The various reactions that
take place in the converter require oxygen, and ideally that should come
from the NOx. If there's an excess of free oxygen in the exhaust, that will
be used to oxidize the CO and HC, in preference to the oxygen that's tied up
in NOx. The reduction of NOx doesn't happen. So run lean, get lower HC and
CO, but more NOx.


And if there's not enough oxygen (ie, engine is running rich), the HCs don't
burn. And the oxid(iz)ation of CO to produce CO2 doesn't happen either. So
run rich, get more CO and HCs.


Lean-burn engines require a different kind of cat, one that accumulates the
NOx. And then, periodically, the system squirts a little extra fuel into
the engine, making it temporarily run rich, so that the cat can get the
right mixture to reduce all the accumulated NOx.


Stoichiometric is the air/fuel ratio that is necessary (in theory) for
perfect combustion. No engine will produce perfect combustion. But a
well-designed system (i.e., engine plus cat) will produce something very
close to it.

 

Mmmfffff!

But the point remains.

 

Wish you could find a still pic. I'm reminded of that lovely shot you
put up, a few months back, of you in your tender youth faffing with some
old steam loco.

 

This one?
http://www.sweller.dynalias.org/images/no7vordb.jpg

I found this rather poor quality scan of me driving:
http://www.sweller.dynalias.org/images/vor_driver.jpg

I have it in Paint Shop Pro format but can no longer open it - can anyone
convert it to jpg? (hopefully it's better quality)
http://www.sweller.dynalias.org/images/vor_driver.psp

I'm guessing it's from 1987; I seem to have lost the pack with all the
originals from that era.