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Discussion Starter #1
hi can anyone tell me the effect of removing the standard headers with catalytic converter and replacing them with a set of non catalytic headers from arrow exhausts , you can replace the CO sensor, thanks
 

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I can't quite grasp what you're actually asking here..?
Are you wondering about pros vs cons of changing the whole exhaust system out with one that doesn't have a cat on it?
 

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Aha, okei then
Well, catalysts became standard on just about all exhaust systems quite a while back. Be it cars, bikes, etc, it was implemented to cut down on the emission from burning fuel. To reduce pollution in other words.
And that's basically it.
On bikes back in the 70's it would make a big difference to remove the cat, as bikes back then was air cooled, and the cat created a lot of back pressure, and thus held onto a lot of heat from the exhaust.
On today's bikes however, the cat hardly makes any back pressure, if any at all. It might be variable from brand to brand, but in general they don't.
Same then goes in regards of the collecting of heat. And many bikes are also liquid cooled these days, so even if it creates a little more heat for the engine, it won't be noticeable.
Another aspect of not having a cat can be the bikes fuel consumption. Might mainly relate to older bikes, but some may suffer a bit higher consumption without the cat, as some engines won't get through a full burn cycle in a proper way, thus sending unburnt fuel down the pipes instead. It's not a high amount all at once, but it will be a steady supply to say, and it will make your exhaust a bit more smoky.
Especially since you'll be driving without a cat, who's job it is to reduce said smoke in the first place.

All of this is mainly in general.

In short however, the cat is purely to cut down on emission, it's not dangerous to drive without it, but it may be illegal some places to do so.
Most people who remove them tend to do so purely due to the look of it, and the sound from it.
Although, not a 100% sure here, but I remember reading about several people in Thailand who had removed the cat, and/or changed the whole exhaust system to one without a cat, wounded up going back to the stock exhaust due to problems.
I don't have any details on what issues they experienced, so sadly I don't have any more info on this.
Might also be more to it than what I'm aware of, so yeah..
But to take a guess at it, I would say it may have screwed up the poor engine, as it is constantly reading the Co2 sensor and making changes to the mixture to get the correct reading it's programmed for. And with no back pressure, and no cat, it may just have been to much for the bike to handle, not being able to find a stable mixture to run steadily on.
There is ofc a little something that you can plug into the bike, to reprogram it's system in regards of the mixture, but that's costly and requires the proper knowledge.
 
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