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Discussion Starter · #1 · (Edited)
I read the other thread on gutting the cats and have a few questions. I would like to remove the the heat caused by the cats.

I do not want to lose any more bottom end by removing the cats.

1. Is the reason for the bottom end loss because of the lack of back pressure from removing the cats?

2. Would just gutting the large cat and leave the small one still create enough back pressure to keep from losing any power, while at the same time remove a lot of the heat source?

3. If I installed the A&R baffles, would I also lose any more back pressure?

4. Would performing the sprocket mod me help me to recover any "power" loss caused by removing cats or just one?

5. Last but not least....I do not have the power commander, but it is my understanding any mapping doesn't affect the bottom end anyway. Most of my riding is street anyway so I do not want to lose any lower range power. I could accept some loss in top-end since I probably would never know it anyway. So would a power commander be really necessary in my application?

Sorry for the long winded post.


AK
 

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I read the other thread on gutting the cats and have a few questions. I would like to remove the the heat caused by the cats.

I do not want to lose any more bottom end by removing the cats.

1. Is the reason for the bottom end loss because of the lack of back pressure from removing the cats?

2. Would just gutting the large cat and leave the small one still create enough back pressure to keep from losing any power, while at the same itme remove a lot of the heat source?

3. If I installed the A&R baffles, would I also lose any more back pressure?

4. Would performing the sprocket mod me help me to recover any "power" loss caused by removing cats or just one?

5. Last but not least....I do not have the power commander, but it is my understanding any mapping doesn't affect the bottom end anyway. Most of my riding is street anyway so I do not want to lose any lower range power. I could accept some loss in top-end since I probably would never know it anyway. So would a power commander be really necessary in my application?

Sorry for the long winded post.


AK
I can answer a couple of questions bottom end?? the engine breathes without the cats, take em both out, the x up valve will give enough back pressure. I did mine some months ago less heat, thats all i did.. Stock pipes have some back pressure, but the low end power dont see it, just wind it up man. Using baffles i would get a power commander as this mod will lean out the fuel ratio.
 

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Malum Prohibitum
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I read the other thread on gutting the cats and have a few questions. I would like to remove the the heat caused by the cats.

I do not want to lose any more bottom end by removing the cats.

1. Is the reason for the bottom end loss because of the lack of back pressure from removing the cats?

2. Would just gutting the large cat and leave the small one still create enough back pressure to keep from losing any power, while at the same itme remove a lot of the heat source?

3. If I installed the A&R baffles, would I also lose any more back pressure?

4. Would performing the sprocket mod me help me to recover any "power" loss caused by removing cats or just one?

5. Last but not least....I do not have the power commander, but it is my understanding any mapping doesn't affect the bottom end anyway. Most of my riding is street anyway so I do not want to lose any lower range power. I could accept some loss in top-end since I probably would never know it anyway. So would a power commander be really necessary in my application?

Sorry for the long winded post.

AK
Here's my .02

R1's run lean from the factory. It you increase the airflow by gutting the cat and installing baffles, you will lean out the bike even further. I have also heard/read that you may get some popping on decell. If I were to do this mod, I would gut the entire cat, put a PCIII on the bike and install the smog block off plates. As far as the gearing, I would do that anyway. (just preference)
 

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My R1 hasn't killed me yet.
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Backpressure is bad, its flow velocity that gives the engine the power down low. The EXUP valve is a simple way to increase velocity at low end while opening up allows good top end power also. All backpressure would do is reduce velocity, its not the same thing.
 

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Discussion Starter · #5 · (Edited)
Backpressure is bad, its flow velocity that gives the engine the power down low. The EXUP valve is a simple way to increase velocity at low end while opening up allows good top end power also. All backpressure would do is reduce velocity, its not the same thing.
Was curious about this since some people have reported a loss of low end power from removing the cats.
I have always thought some back pressure was needed. I am speaking from a low-end standpoint more that top-end.

Was also curious about the power commander because from what I have read, it has no effects on the bottom end anyway. I have read 7000 rpm and below is not even mapped. Not that I even know what mapped means. I am very old-school, and just plain old.


AK
 

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you are going not to loose anything in low end if you gut tha cat (but i would say that there is still much difference by changing it completely with an akra Y, I did both the mods and the akra Y seems to give you more power everywhere instead gutting the cat seem to decrease some mid but I could be wrong or just no feeling difference) if you decide to leave the original pipes,if you plan to gut the cat and change the pipes I suggest you to put a power commander cause it could be too much and going lean...
The best way to go if you use most the bike in street is to buy an akra Y and not to change the pipes (so no mapping needed) ,your bike will perform stronger all the way up in rpm!
However my bike is an euro model and I know for sure there are differences in the way us bikes are mapped ,but I'm sure you don't lose anyway bottom end cause the ecu could adjust fuel in a range of +-10% and something more, but if you live at sea level you could end in something lean, cause once the bike adapt the map with +5% of fuel (for example) you got only another +5% to give depending of how higher are you going from sea level.
I hope you understand what I'm trying to explain,sorry for my english!
 

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Discussion Starter · #7 ·
you are going not to loose anything in low end if you gut tha cat (but i would say that there is still much difference by changing it completely with an akra Y, I did both the mods and the akra Y seems to give you more power everywhere instead gutting the cat seem to decrease some mid but I could be wrong or just no feeling difference) if you decide to leave the original pipes,if you plan to gut the cat and change the pipes I suggest you to put a power commander cause it could be too much and going lean...
The best way to go if you use most the bike in street is to buy an akra Y and not to change the pipes (so no mapping needed) ,your bike will perform stronger all the way up in rpm!
However my bike is an euro model and I know for sure there are differences in the way us bikes are mapped ,but I'm sure you don't lose anyway bottom end cause the ecu could adjust fuel in a range of +-10% and something more, but if you live at sea level you could end in something lean, cause once the bike adapt the map with +5% of fuel (for example) you got only another +5% to give depending of how higher are you going from sea level.
I hope you understand what I'm trying to explain,sorry for my english!
I am at sea level (Miami) So what would that in the performance of my bike if I gut the cats, leave the mufflers as is?

AK
 

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unleash the beast
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I read the other thread on gutting the cats and have a few questions. I would like to remove the the heat caused by the cats.

I do not want to lose any more bottom end by removing the cats.

1. Is the reason for the bottom end loss because of the lack of back pressure from removing the cats?

2. Would just gutting the large cat and leave the small one still create enough back pressure to keep from losing any power, while at the same time remove a lot of the heat source?

3. If I installed the A&R baffles, would I also lose any more back pressure?

4. Would performing the sprocket mod me help me to recover any "power" loss caused by removing cats or just one?

5. Last but not least....I do not have the power commander, but it is my understanding any mapping doesn't affect the bottom end anyway. Most of my riding is street anyway so I do not want to lose any lower range power. I could accept some loss in top-end since I probably would never know it anyway. So would a power commander be really necessary in my application?

Sorry for the long winded post.


AK
Get the y pipe... trust me that would help, also get power commander and get custom mapping....
 
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