2011 gsxr600 cat removal question | GTAMotorcycle.com

2011 gsxr600 cat removal question

danielzak1990

Well-known member
So ive searched this topic everywhere but i couldnt find a straight answer, ive also been to some local bike shops and they werent able to tell me 100% either.

I have 2011 suzuki gsxr600 with yoshimura r77d slip on, and i want to remove the cat.
I was going to order 'mjs midpipe' weld on version. But from what i know that will cause the 'FI' light to come on. Right ???
Will the pc5 and a custom map fix the fi light issue?
No one was able to give me a straight answer on this. Maybe someone here has done it.
 
So ive searched this topic everywhere but i couldnt find a straight answer, ive also been to some local bike shops and they werent able to tell me 100% either.

I have 2011 suzuki gsxr600 with yoshimura r77d slip on, and i want to remove the cat.
I was going to order 'mjs midpipe' weld on version. But from what i know that will cause the 'FI' light to come on. Right ???
Will the pc5 and a custom map fix the fi light issue?
No one was able to give me a straight answer on this. Maybe someone here has done it.

I've done the mod for others and I pulled a wire from the Ecu to eliminate the FI light. And the FI light comes from removing the servo and valve not the cat.
 
Maybe you can be lazy and just zip-tie the servo out of sight somewhere.
 
I've done the mod for others and I pulled a wire from the Ecu to eliminate the FI light. And the FI light comes from removing the servo and valve not the cat.

Well i wont be touching the servo or set valve , i will be cutting after all that stuff right before where the cat begins. So from what ur saying i should be fine and the fi light wont come on ?
 
The catalyst is not monitored by the ECU in your bike, if that is what you are asking. The ECU has no way of knowing whether the catalyst exists, so therefore it cannot trip a fault code solely because of that.
 
So ive searched this topic everywhere but i couldnt find a straight answer, ive also been to some local bike shops and they werent able to tell me 100% either.

I have 2011 suzuki gsxr600 with yoshimura r77d slip on, and i want to remove the cat.
I was going to order 'mjs midpipe' weld on version. But from what i know that will cause the 'FI' light to come on. Right ???
Will the pc5 and a custom map fix the fi light issue?
No one was able to give me a straight answer on this. Maybe someone here has done it.

It will cause your GSXR to have a pop sound on de-accel... also shoot blue flames.

That's no cat, stock exhaust...
 
You won't set any codes. Your mid-pipe will come with a bung for your 02 sensor and you're cutting after the SET valve as seen here:

http://www.youtube.com/watch?v=ylgLFVvECbY&sns=em

Cut as close to the cat side as you can.

You'll get some after-fire (popping on decel). Nothing to worry about tho. Take it for a custom flash if you're gonna keep the R-77 on it permanently.
 
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As stated, if your ex valve and o2 are still in place no fi code. If you decide to remove set valve yosh web site shows you which wire to disconnect Some other brands like leo vince use a plate that attaches to the servo motor, instead of disconnecting the wire.
 
The catalyst is not monitored by the ECU in your bike, if that is what you are asking. The ECU has no way of knowing whether the catalyst exists, so therefore it cannot trip a fault code solely because of that.

Some model have 02 sensors before and after the cat, which in effect tells the ECU if there is a cat or not.

Honestly, why do this? Not enough pollution around?
 
Some model have 02 sensors before and after the cat, which in effect tells the ECU if there is a cat or not.

Honestly, why do this? Not enough pollution around?

I bought the yoshimura slip on, thinking the bike will have a nicer sound to it , and to be honest its not much different than the stock.
It screams a bit louder at around 10k rpm, but i cant say i noticed much difference.
Thats the only reason im cutting it out.
 
I bought the yoshimura slip on, thinking the bike will have a nicer sound to it , and to be honest its not much different than the stock.
It screams a bit louder at around 10k rpm, but i cant say i noticed much difference.
Thats the only reason im cutting it out.

If its just about noise, look to a tail pipe slipon, like motogp, or nothing but a pipe.
 
If its just about noise, look to a tail pipe slipon, like motogp, or nothing but a pipe.

His bike has a cat built into the exhaust headers, leaving that intact no matter what brand or style slip on pipe he puts on it after the cat it will not get that much louder or better sounding. As the cat sets the overall tone and loudness, so removing that is step number one....

I have done this a few times on GSXR's with the cat in the header, the same happens with 09-14 ZX6R's which also have a cat....If you dont remove it, you are not going to get the sound and performance you will after you remove it...

Some companies make a link pipe to remove them, other times I have just cut the exhaust pipe just before the cat, then use a slipon from the previous generation of GSXR that didnt have the cat.....Some say it needs welding, but I did it without welding, if you cut in the right spot there is enough pipe left over for the slipon to grab onto... And its a world of difference in sound once you remove the cat

If you also want to remove the exhaust servo and valve, there is one wire in the ECU wiring harness that needs to be pulled out to eliminate the FI warning light...Its all over google and youtube, its one wire you simply find in the harness and cut or just use a terminal puller to pull it out from the harness clip. Its a 5 min mod to find the correct wire and pull it out or cut it
 
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I bought the yoshimura slip on, thinking the bike will have a nicer sound to it , and to be honest its not much different than the stock.
It screams a bit louder at around 10k rpm, but i cant say i noticed much difference.
Thats the only reason im cutting it out.

The M4 comes with the mid-pipe (does for the 1000's), with a bung for your 02 sensor and has two silencers. It's a simple install. The Stage 2 silencer won't have every cop in the area looking at you. The cat has to come off to reach the sort of growl that you're looking for with the R-77. Again, you don't need to disable the SET valve, it's job is to give you some back pressure at low RPM's, which you need, or you'll have no power down low. It's only closed at idle and very low RPM's. It helps the engine warm up too. The only diff you'll notice if you disable it is more growl at idle and a bike that takes forever to warm up. And you may get smoked off the line by other 600's as all your back pressure is gone. Down low you need back pressure, up high (RPM's) you need flow, which is exactly what the SET valve does for you. (SET = Suzuki Exhaust Timing).

You won't get this kind of growl from the R-77 even with cat removed, but they still sound nice, especially up high:

http://www.youtube.com/watch?v=Hb5qYvzeY4Y&sns=em

If you want more noise at all RPM's you'll need the M4 or Racefit Growler or Jardine.
 
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The M4 comes with the mid-pipe (does for the 1000's), with a bung for your 02 sensor and has two silencers. It's a simple install. The Stage 2 silencer won't have every cop in the area looking at you. The cat has to come off to reach the sort of growl that you're looking for with the R-77. Again, you don't need to disable the SET valve, it's job is to give you some back pressure at low RPM's, which you need, or you'll have no power down low. It's only closed at idle and very low RPM's.

Its never "closed" when the bike is running. Its always open a little.......The only time it actually closes all the way is when you turn on the bike, it cycles all the way closed then all the way open, then to about 1/4 open for idle....

You dont have to loose all your bottom end when you remove them, but generally you need custom tuning to make sure that doesnt happen.....All full systems I have seen or installed for those bikes do not use a set valve, and they do not make the bike loose all its bottom end if you have the correct mapping...Using the stock mapping and removing it will obviously not run properly, as its a drastic change to the A/F ratio that the ECU can not adjust for...

Either way Ive done it with and without with good results, Akra full system and mapping does pretty darn good wihtout a set valve....Also have done with Yosh slipon and power commander with tuning and good results for a street rider, he never complained about not having torque...

However on the flip side someone came to me with a ZX6R with M4 and no cat and no mapping, he complained that he lost all torque when he installed it. He did not want to spend money on power commader/Bazzaz or any kind of tuning. So for him I offered to sell him another slipon that retains the cat, simply swapping out the 2 slipons and putting the cat back on made all his bottem end come back....Its not that he removed the car or the valve, its that he didnt want to spend the money required to tune the issues removing them caused out....

PS its Suzuki exhaust tuning I believe not timing
 
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The M4 comes with the mid-pipe (does for the 1000's), with a bung for your 02 sensor and has two silencers. It's a simple install. The Stage 2 silencer won't have every cop in the area looking at you. The cat has to come off to reach the sort of growl that you're looking for with the R-77. Again, you don't need to disable the SET valve, it's job is to give you some back pressure at low RPM's, which you need, or you'll have no power down low. It's only closed at idle and very low RPM's. It helps the engine warm up too. The only diff you'll notice if you disable it is more growl at idle and a bike that takes forever to warm up. And you may get smoked off the line by other 600's as all your back pressure is gone. Down low you need back pressure, up high (RPM's) you need flow, which is exactly what the SET valve does for you. (SET = Suzuki Exhaust Timing).

You won't get this kind of growl from the R-77 even with cat removed, but they still sound nice, especially up high:

http://www.youtube.com/watch?v=Hb5qYvzeY4Y&sns=em

If you want more noise at all RPM's you'll need the M4 or Racefit Growler or Jardine.

And that video, that is the exact same pipe and bike that the customer came to me with that sucked *** on stock mapping......Not sure what that insert will do, but that pipe on that bike completely sucks with no mapping..The no torque thing is 100% true on that one if you dont tune it
 
Some model have 02 sensors before and after the cat, which in effect tells the ECU if there is a cat or not.

Honestly, why do this? Not enough pollution around?

The pre- and post-catalyst sensors are on OBDII cars (every gas engine car after 1996 - diesels are a different matter). Motorcycles are not (yet) required to have OBDII. In some ways, that's good ... if you want to modify a.k.a. tamper. In other ways, it's frustrating, because OBDII standardized all emission-related trouble codes, diagnostic ports, communication protocols, etc between manufacturers so you only need one scan tool (in theory). OBDII also standardized the way trouble codes are "remembered". Having just been through an exercise with one bike in which it lit the MIL, but the process of getting to the diagnostic port involved stopping the engine which caused the ECU to "forget" all its troubles ... OBDII is not all bad.

If your question was really "why remove the catalyst" ... personally, all of my road-legal vehicles that came with a catalyst, still have it. Modern catalysts don't hamper performance in any meaningful way.
 
The pre- and post-catalyst sensors are on OBDII cars (every gas engine car after 1996 - diesels are a different matter). Motorcycles are not (yet) required to have OBDII. In some ways, that's good ... if you want to modify a.k.a. tamper. In other ways, it's frustrating, because OBDII standardized all emission-related trouble codes, diagnostic ports, communication protocols, etc between manufacturers so you only need one scan tool (in theory). OBDII also standardized the way trouble codes are "remembered". Having just been through an exercise with one bike in which it lit the MIL, but the process of getting to the diagnostic port involved stopping the engine which caused the ECU to "forget" all its troubles ... OBDII is not all bad.

If your question was really "why remove the catalyst" ... personally, all of my road-legal vehicles that came with a catalyst, still have it. Modern catalysts don't hamper performance in any meaningful way.

Besides weight? Minimal and not a factor for most, but cats do weight a lot......Huge difference if you compare the whole unit, to say a full Ti system with no cat....

I believe some of the GSXR's came with 02 and some didnt. and it depends on the market the bike was made for also, as some kits I have installed came with a plug in eliminator for the the 02 sensor.....When the bike the kit was bought for didnt even have one to begin with.....

I just did a servo removal on a 2002 954 with PCV, and it came with a plug in eliminator for something that wasnt even on the bike....Possibly the euro or cali model did and the include it just in case you have that ?
 
And that video, that is the exact same pipe and bike that the customer came to me with that sucked *** on stock mapping......Not sure what that insert will do, but that pipe on that bike completely sucks with no mapping..The no torque thing is 100% true on that one if you dont tune it

You own your own dyno? Are you flashing ECU's or using auto-tuners?
 

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