Removing Catalytic Converter

AML

AML

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So another noob question :)

If I did remove it what kind of gains would I get?

Do you loose milage?

Its sort of important for me to ask because the bike needs to pass a test after 3 years and if I remove it, It wont pass.

So for me it means having to buy a second header and keeping one with the Cat, just for that test.

So if I dont get much more HP and I loose milage then im thinkin to just leave it.
 
where is it ur from ?? we dont have emissions test on bikes in the uk ???

and gutting the cat DOES give power gains, not sure on numbers but it allows for better flow.

seth
 
I live in Japan and on a new bike we have a test after 3 years.

After that its every 2 years.

They check emissions and noise levels.

I actually found the thread about the Cat on the next page so never mind guys : oops:
 
AML said:
So another noob question :)

If I did remove it what kind of gains would I get?

Do you loose milage?

Its sort of important for me to ask because the bike needs to pass a test after 3 years and if I remove it, It wont pass.

So for me it means having to buy a second header and keeping one with the Cat, just for that test.

So if I dont get much more HP and I loose milage then im thinkin to just leave it.
Click to expand...

If you have do deal with emissions then I would just leave it alone. Removing the cat wont probably impact your mileage much one way or the other. Probably worth about 2-3 RWHP mostly on the top end. I know you're already planning on doing the slip-on Yosh and that's going to give you the bigger gain. I guess you'll need to reinstall the stock muffler when it's time to pass emissions since there in a cat in there as well.
 
AML said:
So another noob question :)

If I did remove it what kind of gains would I get?

Do you loose milage?

Its sort of important for me to ask because the bike needs to pass a test after 3 years and if I remove it, It wont pass.

So for me it means having to buy a second header and keeping one with the Cat, just for that test.

So if I dont get much more HP and I loose milage then im thinkin to just leave it.
Click to expand...

Okay lets look at this in reality. Back in the early seventies when catalytic converters were first employed, they were first introduced by GM and were a chamber of beads of a precious metal. Its only requirement was that leaded gasoline would kill the catalytic converter so we had to switch to unleaded. Lead was used in gasoline to cool and cushion exhaust valves. If you added leaded gasoline to a vehicle equipped with a catalytic converter it would cause it to overheat and melt therefore clogging the converter.

Fast forward to 2010 (37 years). Almost all of the current cats are of a full flow honeycomb design with almost no impediment to exhaust flow. The surface area of the honeycomb design was able to reduce the size of the catalytic converter and meet emission standards. Leaded gas has been phased out and life is good for your children.

Yes a full race four into one exhaust will give you the best peak horsepower, but how do you ride your bike on a daily basis. Somewhere around 5-7thou RPM or 12-14thou. We could get into volumetric efficiency at this time but there’s not enough space.

My thoughts are this, change to a slip on muffler, leaving the stock header pipe & and cat in place. Enjoy the hell out of your bike. Change back to the stock muffler for inspection. Switch back when you are done.

Removing the catalytic converter increases the impression ratio only. Your ass will never feel the difference in power.

Mt two sense. :box:
 
There will be a big change in sound just by adding the slip on. You will be losing 1 cat that is in the stock can and you will also lose the EXUP valve. You will be making music..
 
FastRnu2 said:
Okay lets look at this in reality. Back in the early seventies when catalytic converters were first employed, they were first introduced by GM and were a chamber of beads of a precious metal. Its only requirement was that leaded gasoline would kill the catalytic converter so we had to switch to unleaded. Lead was used in gasoline to cool and cushion exhaust valves. If you added leaded gasoline to a vehicle equipped with a catalytic converter it would cause it to overheat and melt therefore clogging the converter.

Fast forward to 2010 (37 years). Almost all of the current cats are of a full flow honeycomb design with almost no impediment to exhaust flow. The surface area of the honeycomb design was able to reduce the size of the catalytic converter and meet emission standards. Leaded gas has been phased out and life is good for your children.

Yes a full race four into one exhaust will give you the best peak horsepower, but how do you ride your bike on a daily basis. Somewhere around 5-7thou RPM or 12-14thou. We could get into volumetric efficiency at this time but there’s not enough space.

My thoughts are this, change to a slip on muffler, leaving the stock header pipe & and cat in place. Enjoy the hell out of your bike. Change back to the stock muffler for inspection. Switch back when you are done.

Removing the catalytic converter increases the impression ratio only. Your ass will never feel the difference in power.

Mt two sense. :box:
Click to expand...

Its been Dyno proven the on the Gen II your biggest gains are with a aftermarket header. As a bonus the largest power increase is smack dab in the mid range right were you want it. Any where from 20 to 30 HP at 7500
 
In my 46 (going into 47) years riding street bikes, I've seen a lot of money go down the drain in the name of making more power. In my early days I was starting with ten, maybe fifteen OEM H.P. trying to squeeze out maybe eleven or sixteen. Just as today, many times the bike got louder and the brain translated that into more power but the actual increase was very hard to measure, at least in the real world. As I matured I made a couple rules. Don't do something that can't be undone, and don't spend a bunch of money that can't be at least partially be reclaimed.

With a starting point of 120-130 horses, an additional 20 or so is useless on the street anyway and unless you like to do a lot of work on the track you'll be stacking up speeding tickets in a hurry, then you won't be riding anyway. There are plenty of things you can add to a bike to make it fit your desires that will also alow you to return it to stock and you can recoup your investment by selling it. Doing unrepairable damange to you exhaust AINT going to make your bike that much more of a fireburner and you very well may regret doing it in the first place. Take it from an Old fart who has pissed away more money than I wish I could remember and I'm sure there's a bunch I can't.
 
FastRnu2 said:
Okay lets look at this in reality. Back in the early seventies when catalytic converters were first employed, they were first introduced by GM and were a chamber of beads of a precious metal. Its only requirement was that leaded gasoline would kill the catalytic converter so we had to switch to unleaded. Lead was used in gasoline to cool and cushion exhaust valves. If you added leaded gasoline to a vehicle equipped with a catalytic converter it would cause it to overheat and melt therefore clogging the converter.

Fast forward to 2010 (37 years). Almost all of the current cats are of a full flow honeycomb design with almost no impediment to exhaust flow. The surface area of the honeycomb design was able to reduce the size of the catalytic converter and meet emission standards. Leaded gas has been phased out and life is good for your children.

Yes a full race four into one exhaust will give you the best peak horsepower, but how do you ride your bike on a daily basis. Somewhere around 5-7thou RPM or 12-14thou. We could get into volumetric efficiency at this time but there’s not enough space.

My thoughts are this, change to a slip on muffler, leaving the stock header pipe & and cat in place. Enjoy the hell out of your bike. Change back to the stock muffler for inspection. Switch back when you are done.

Removing the catalytic converter increases the impression ratio only. Your ass will never feel the difference in power.

Mt two sense. :box:
Click to expand...


Tetraethyl lead was added to gasoline primarily to raise octane/eliminate pre-ignition. It also had some lubricating properties.
 
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