Removed the catalyst from the head pipes
Tourer
Joined: Dec 2010
Posts: 381
Likes: 0
From: Longwood, Fl
I am the same way James. If I need to go fast, I have a 554hp Cobra that gets the job done! If you have not noticed any issues with your 02's being unplugged, it makes me wonder why they are there in the first place. Does the check engine come on?
Seasoned HDF Member
Joined: Jan 2007
Posts: 20,616
Likes: 4,440
From: anacoco, la
i've been running a gutted headpipe for 9 months now. no other changes, except for the nightstick replacing the stock muffler. stock ac. mileage runs 45mpg or better, plugs look nice (but we all know that that isn't a good indicator anymore with fi), bike runs strong. as far as i can tell, i do not have a problem with 'cross talk' between the o2 sensors. i have no trouble codes stored. no cel light on.
maybe one day, i'll do the full stage 1. i like the new dynojet powervision. but, not in a big hurry.
maybe one day, i'll do the full stage 1. i like the new dynojet powervision. but, not in a big hurry.
Road Warrior
Joined: Jul 2010
Posts: 1,816
Likes: 2
From: New Hampshire
I bought a gutted 2010 2-2 headpipe on Ebay a month or so ago. With all this talk about pieces of the cat being sucked back into the exhaust port.I dropped an email to the person I bought it from and asked about how he cleaned the part where cat was.
He said after he cuts the cat out that he files the inside slightly and runs a 1 3/4 wire wheel to try and get any loose material out. He suspects that issues could be happening with some people just running a concrete coring bit though the cat just to punch a hole in it. That could open up pieces coming off in that case which makes sense
Is the bike much louder without the cat.....? I sort of like the volume of the bike now but would like more of a low rumble without my ears ringing....gotta protect the hearing!
He said after he cuts the cat out that he files the inside slightly and runs a 1 3/4 wire wheel to try and get any loose material out. He suspects that issues could be happening with some people just running a concrete coring bit though the cat just to punch a hole in it. That could open up pieces coming off in that case which makes sense
Is the bike much louder without the cat.....? I sort of like the volume of the bike now but would like more of a low rumble without my ears ringing....gotta protect the hearing!
Road Warrior
Joined: Jan 2010
Posts: 1,290
Likes: 20
From: Salem, Or
You are correct. They won't cross talk. The sensor for the rear pipe screws all the way into the pipe and is totally seperated from the sensor for the front pipe.
Outstanding HDF Member
Joined: Oct 2007
Posts: 3,437
Likes: 15
You are not taking in to account reversion negative pulse wave comeing back up the pipe. The cat material acts as a barrier to slow down the negative pulse wave before it hits the senosrs. When the cat is removed nothing is there in the void to prevent the cross talk. I thought the same thing but after cutting my exhaust in two and removing the cat I can see how they can be affected. Doc Weaver of Doc's performace knows his stuff about tuning. He is the one who brought me up to date on this.
Last edited by mtclassic; Jan 15, 2011 at 10:59 AM.
Ultimate HDF Member
Joined: Feb 2010
Posts: 8,039
Likes: 1,305
From: Jayhawk Country
Yep, the old reversion negative pulse wave will get you every time. But seriously, lots of folks here have gutted the CAT with no adverse affects.
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Stellar HDF Member
Joined: Jan 2008
Posts: 3,036
Likes: 65
From: Earth
You are not taking in to account reversion negative pulse wave comeing back up the pipe. The cat material acts as a barrier to slow down the negative pulse wave before it hits the senosrs. When the cat is removed nothing is there in the void to prevent the cross talk. I thought the same thing but after cutting my exhaust in two and removing the cat I can see how they can be affected. Doc Weaver of Doc's performace knows his stuff about tuning. He is the one who brought me up to date on this.
Outstanding HDF Member
Joined: Oct 2007
Posts: 3,437
Likes: 15
Jeff
There is one 02 sensor that is in a tube and but the other is not protected because it is in the big void that the cat used to fill. The Cat provides enough back pressure to protect the one sensor in the big area and the cat stops 99% or the reversion (negitive pulse wave) coming back up the pipe. When you remove the cat reversion takes over taht void and the 02 sensors will now cross talk........I know this for a fact Jeff I'm not guessing or blowing smoke. Both 02 sensors have to be in a tube at least 6'' to stop the cross talk.
Doc