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Discussion Starter #1
I've got an Australian model and I'm just wondering if I would have this PAIR system, should I remove it if I'm not getting it dynotuned?
 

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As far as I know both US and EU spec bikes have it.

The PAIR system pumps fresh air into the exhaust stream to reduce the concentration of emissions, and that of course compromises the readings of self-tuning modules that depend on data the sensor picks up to understand how the engine is running. So removing it is better than keeping it in all cases whether you choose to self-tune, dyno-tune or no tune.
 

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Discussion Starter #5
Thanks guys, I may consider it when I get a full system and then do a tune, for now I think I should be fine.
 

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The system is in place to provide oxygen to allow unburned fuel to burn off in the exhaust tract . Its not for dilution. This extra burn also raises egts and keeps the cat working optimally
 

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The system is in place to provide oxygen to allow unburned fuel to burn off in the exhaust tract . Its not for dilution. This extra burn also raises egts and keeps the cat working optimally
To quote the manual:

The secondary air supply system introduces filtered air into exhaust gases in the exhaust port. The secondary air is drawn whenever there is negative pressure pulse in the exhaust system. This charged secondary air promotes burning of the unburned exhaust gases and changes a considerable amount of hydrocarbons and carbon monoxide into relatively harmless carbon dioxide and water.
 

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To quote the manual:

The secondary air supply system introduces filtered air into exhaust gases in the exhaust port. The secondary air is drawn whenever there is negative pressure pulse in the exhaust system. This charged secondary air promotes burning of the unburned exhaust gases and changes a considerable amount of hydrocarbons and carbon monoxide into relatively harmless carbon dioxide and water.
I remember reading that and perhaps a chemist could confirm this, because it's been a while since I've dealt with it, but if air is about 78% N2, wouldn't compounds like N2O which IIRC creates smog and other bad stuff then be released in higher quantities?
 

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Rad... The manual is saying what I just did.

Kat, the catalytic converter deals with these things
I thought so...I guess what I'm wondering is if for some reason or another the bike doesn't have a cat anymore, wouldn't extra air going into the exhaust be bad with respect to emissions?
 

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Emissions are more harmful when the mixture is rich. So essentially yes. The pair essentially leans the mixture once its out of the combustion chamber.
 

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Sorry. Pair will allow for less harmful emissions when used without a cat. Fuel burned completely is less harmful than fuel that burns in a rich condition
 

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the simple solution is energy density.

light crude has a massive amount of potential energy, and it doesn't take much energy expenditure to get it.

a lot of the other technologies that people are trying to get at require substantial energy expenditure just to get the fuel (hydrogen fuel cells come to mind).

electric is another issue because batteries aren't there yet when it comes to energy density, and they also require an energy injection from another energy source, which for the most part currently is fossil fuels.

the best solution honestly is nuclear. but the public won't allow that. so we're kinda fucked.
 
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