De-smog question

[zippychips]

Guys

ive de-activated the stupd emissions thing on the side of the dommy but was curious to know what you guys done with the pipe that runs from the carb to the smog valve thingy ?

[Mervinh]

blocked em off
merv

[twistgrip]

I know this device is a sham to reduce emissions and I even had it on an Indian heap of sh(bullet)it but does it reduce performance? If it doesn't why bother removing it. It's on the Vigor I have but what would I gain if I took it off?

[Axe]

Is this the same as an EGR valve that you get on some cars?

If so then removing it will increase performance, The EGR sends some of your exhaust gasses back into the cylinder for the next power stroke, The heat provided by the exhaust helps the fuel evaporate better providing a better mix for the next burn, but at the expense of some of the oxygen that you get with the next clean air/fuel charge.

A cold charge is denser than a warm one so you get more oxygen, no exhaust gasses leaves more space for fresh air/fuel.
So no EGR wins on 2 counts.

The downside is that your emissions suffer as burning some of the exhaust gases gets rid of more of the polutants so lowers emmisions figures.
(this doesn't matter in the UK as bikes do not have to pass an annual emissions test, only the type approval one)

If the Anti Smog isn't the same as EGR then ignore everything I just typed.

Axe.

[Mervinh]

all the smog thing does is intorduces air into the exhaust ports therefore makng the emissions seem cleaner, but it is in fact just fooling emissions tests, it does not help performance and causes a lot of popping in the exhaust,
I spoke to my local bike shop about it, and he says they serve no purpose, he removes them when fitting aftermarket exhausts as they cause a lot of popping and banging in the exhausts on the dyno he said

i removed the one from my vigor and it does seem smoother now and appears to pull better

[twistgrip]

Ah! so that explains the occasional popping in my exhaust. I've no need to worry now. Thought I had a leak or running weak. Think I'll leave mine alone. Thing is Honda etc spend sheds on developing a model or refining it and as their resources are greater than mine I'll leave well alone. Don't mean it can't be removed if you choose though.

[Rubberchicken]

I spoke to my local bike shop about it, and he says they serve no purpose, he removes them when fitting aftermarket exhausts as they cause a lot of popping and banging in the exhausts on the dyno he said

Not just popping and banging... Especially on the dyno it will be hard to measure the mixture correctly if some wossname is injecting clean air into the exhaust.

Took mine off when I was fiddling with the jets. Ran better after the next dyno run, cooler too somehow.

And hey, it saves weight.

[SiNX650]

Anyone have pics of this smog thing?.

Found a NX650 Smog Block Off Plate Kit on ebay, I guess this will be needed after it's taken off?.

Thanks.

[SiNX650]

Is it the cylindrical thing with pipes coming out of it below the fuel tap?.

[Mervinh]

Se the red arrow that is the accused