no cat with stock mufflers
Cruiser
Joined: Feb 2014
Posts: 167
Likes: 13
From: Albemarle, NC
No. But it should. To summarize what's been posted here--The cat is not restrictive. Removing it hurts performance.
As far as heat is concerned, here's what p51bombay's tests showed:
Without a cat and with lower fairings -- the area where the cat had been was actually hotter than the header pipe where it exits the cylinder. 675 degrees at the cylinder vs. 775 degrees at the cat.
With a cat and with lower fairings-- 750 degrees at the cylinder and 920 degrees at the cat
With a cat and without lower fairings-- temps are lower in both locations, 640 degrees at the cylinder at 800 degrees at the cat.
***************
So, for those of you with lower fairings, if these tests are accurate, you can potentially reduce the heat from the cat by 170 degrees, from 920 degrees to 775 degrees. In layman's terms that's a reduction from Very, Extremely MotherF'ing Hot down to Extremely MotherF'ing Hot. I challenge anyone to tell the difference between 920 degrees and 775 degrees with their foot (or any other part of their anatomy).
For those of us that don't have lower fairings, there is very little to be gained and performance to be lost by removing the cat.
As far as heat is concerned, here's what p51bombay's tests showed:
Without a cat and with lower fairings -- the area where the cat had been was actually hotter than the header pipe where it exits the cylinder. 675 degrees at the cylinder vs. 775 degrees at the cat.
With a cat and with lower fairings-- 750 degrees at the cylinder and 920 degrees at the cat
With a cat and without lower fairings-- temps are lower in both locations, 640 degrees at the cylinder at 800 degrees at the cat.
***************
So, for those of you with lower fairings, if these tests are accurate, you can potentially reduce the heat from the cat by 170 degrees, from 920 degrees to 775 degrees. In layman's terms that's a reduction from Very, Extremely MotherF'ing Hot down to Extremely MotherF'ing Hot. I challenge anyone to tell the difference between 920 degrees and 775 degrees with their foot (or any other part of their anatomy).
For those of us that don't have lower fairings, there is very little to be gained and performance to be lost by removing the cat.
The cat is not restrictive.
The cat is restrictive.
Removing it hurts performance.
Removing it does not hurt performance.
The one thing everyone seems to agree on is that the cat produces more heat so you will get less heat in that area with it removed.
Cruiser
Joined: Feb 2014
Posts: 167
Likes: 13
From: Albemarle, NC
No. But it should. To summarize what's been posted here--The cat is not restrictive. Removing it hurts performance.
As far as heat is concerned, here's what p51bombay's tests showed:
Without a cat and with lower fairings -- the area where the cat had been was actually hotter than the header pipe where it exits the cylinder. 675 degrees at the cylinder vs. 775 degrees at the cat.
With a cat and with lower fairings-- 750 degrees at the cylinder and 920 degrees at the cat
With a cat and without lower fairings-- temps are lower in both locations, 640 degrees at the cylinder at 800 degrees at the cat.
***************
So, for those of you with lower fairings, if these tests are accurate, you can potentially reduce the heat from the cat by 170 degrees, from 920 degrees to 775 degrees. In layman's terms that's a reduction from Very, Extremely MotherF'ing Hot down to Extremely MotherF'ing Hot. I challenge anyone to tell the difference between 920 degrees and 775 degrees with their foot (or any other part of their anatomy).
For those of us that don't have lower fairings, there is very little to be gained and performance to be lost by removing the cat.
As far as heat is concerned, here's what p51bombay's tests showed:
Without a cat and with lower fairings -- the area where the cat had been was actually hotter than the header pipe where it exits the cylinder. 675 degrees at the cylinder vs. 775 degrees at the cat.
With a cat and with lower fairings-- 750 degrees at the cylinder and 920 degrees at the cat
With a cat and without lower fairings-- temps are lower in both locations, 640 degrees at the cylinder at 800 degrees at the cat.
***************
So, for those of you with lower fairings, if these tests are accurate, you can potentially reduce the heat from the cat by 170 degrees, from 920 degrees to 775 degrees. In layman's terms that's a reduction from Very, Extremely MotherF'ing Hot down to Extremely MotherF'ing Hot. I challenge anyone to tell the difference between 920 degrees and 775 degrees with their foot (or any other part of their anatomy).
For those of us that don't have lower fairings, there is very little to be gained and performance to be lost by removing the cat.
The cat is not restrictive.
The cat is restrictive.
Removing it hurts performance.
Removing it does not hurt performance.
I haven't seen any independent tests showing loss of power by removing the cat or measurements of restriction, only opinions. The one thing everyone seems to agree on is that the cat produces more heat so you will get less heat in that area with it removed. If you're in favor of cats though it seems that heat doesn't matter. I'll be the judge of whether I feel less heat.
Tourer
Joined: Jul 2007
Posts: 369
Likes: 139
From: Minnesota
2012 FLHTCU 103 de-catted
I de-catted a stock head pipe and still run OEM mufflers. I had previously installed XiEDs. After removing the cat, it is cooler, it is slightly louder with deeper sound, performance seems the same, if there was any loss or gain, it isn't noticeable.
I am very happy with the de-catted the head pipe.
I am very happy with the de-catted the head pipe.
Intermediate
Joined: Mar 2014
Posts: 36
Likes: 0
From: Denver
I replaced my stock header with a cat-less header from American Custom. Cost was reasonable, fit right on without a hitch. Installed in hopes of reducing heat.
I've been running stock pipes and air filter.
I'm now moving to an S&S Stealth air filter system, V&H Fuelpak 3, and SE Street Cannons.
Anybody running a similar system?
Thanks
I've been running stock pipes and air filter.
I'm now moving to an S&S Stealth air filter system, V&H Fuelpak 3, and SE Street Cannons.
Anybody running a similar system?
Thanks
Ultimate HDF Member
Joined: Jun 2010
Posts: 5,105
Likes: 16
From: Blaine, WA
I replaced my stock header with a cat-less header from American Custom. Cost was reasonable, fit right on without a hitch. Installed in hopes of reducing heat.
I've been running stock pipes and air filter.
I'm now moving to an S&S Stealth air filter system, V&H Fuelpak 3, and SE Street Cannons.
Anybody running a similar system?
Thanks
I've been running stock pipes and air filter.
I'm now moving to an S&S Stealth air filter system, V&H Fuelpak 3, and SE Street Cannons.
Anybody running a similar system?
Thanks
Road Master
Joined: Oct 2007
Posts: 915
Likes: 29
From: SE FL & Black Hills SD
Just back from another test run and the results are pretty surprising.......for me at least, I did not expect to see this much of a change. The funny thing is the only thing I changed from the previous test was...........wait for it.........I pulled off both fairing lowers. The effect was immediately apparent, even before I hit the freeway. Same as before, 70mph, 6th gear cruise and the front head pipe measures 640F, that's around 110F cooler simply by removing the fairing lowers and this is at the pipe, not my foot although its pretty obviously cooler there too.......
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Road Warrior
Joined: Aug 2008
Posts: 1,784
Likes: 92
From: Michigan
LMAO at people that think sitting on top of a liquid cooled engine is like an ice cube in comparison to an air cooled motor. It's still hot weather the movement of the bike is blowing it back at you or the radiator fans are.
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