Cat Headers are so bad?
Road Warrior
Joined: Jun 2007
Posts: 1,788
Likes: 4
From: Here
With the CAT removed they let the exhaust flow less restrictive & the sound difference is significantly better at least with aftermarket slip ons. I'm running the V&H Hi Flows & so is my brother & my 08 with NO-CAT is significantly louder than my brothers RG with the same mufflers. That alone tells me it is restrictive....
Road Warrior
Joined: Jul 2010
Posts: 1,816
Likes: 2
From: New Hampshire
I'm sticking with the cat for awhile...I like the sound I'm getting now out of my Supertrapps...both tone and volume wise. The heat has not been awful as of yet
I will agree that the header pipe is an interesting mix of gold and blue lol
I will agree that the header pipe is an interesting mix of gold and blue lol
Thread Starter
|
Intermediate
Joined: Oct 2007
Posts: 38
Likes: 0
Thanks for the answers!!!
So as a conclusion:
1-Cat= more heat, less sound and similar power
2-No Cat= less heat, hi sound and, little more power
I'll try keeping the cat, and see myself if heat and less sound means a problem for me, I think that the main think for me is power.
So as a conclusion:
1-Cat= more heat, less sound and similar power
2-No Cat= less heat, hi sound and, little more power
I'll try keeping the cat, and see myself if heat and less sound means a problem for me, I think that the main think for me is power.
Road Warrior
Joined: Mar 2008
Posts: 1,783
Likes: 10
From: Oh
It seems whether you live north or south of the Mason Dixon determines whether the cat is hot enough for you or not. People living down south have to live with more heat and are more prone to take out the cat. Removing the cat whether by cutting it out or a new head pipe WILL reduce the heat on you and your passenger. Along with a high flow air filter and tune to richen it slightly, will remove most of the heat while increasing performance. I am of the opinion it also restricts flow.
Outstanding HDF Member
Joined: Jan 2010
Posts: 2,916
Likes: 31
From: earth
Oh yeah them cats is restrictive as all git out, just look at the picture of one cut in half, and the sound, and the heat, that right there tells you its restrictive, Yeah boy that cat chokes off a whole buncha power, NOT. I'll be the first to claim that HD has made a lot design and engineering blunders over the years, but do you really believe they are so dumb that they used a catalyst design that would further inhibit their already anemic power plants. Please someone with the resources, do a before and after flow test on the cat removal, because the dyno test showing no diference in power is not enough evidence for a whole bunch of people. I just put the 2:1 OEM catalyst pipe back on my bike while I get my FM pipe repaired, no dyno sheets, it lost a little power but it still runs pretty damn good, Had I run it first I would have been real disappointed in the FM pipe. The little bit of power I did lose is not because of the cat, its due to the sharp bend on the rear pipe and the collector outlet being smaller than the primaries, measurably choking it off. Yeah buddy, that CAT's a big ol restriction ya best cut it out of there and unleash a bunch of free power.
Tourer
Joined: Jul 2011
Posts: 299
Likes: 1
From: Ct.
Live in Ct, and on a 2.5 hr trip to the cape on a 93 degree morning my wife said the heat on the right side was almost unbearable. Then we hit traffic at the bourne bridge, and the heat was out of control.
Fortunately we were travelling in proximity to my father in a car. We stopped he picked up the wife, and I continued on. A week later the cat was removed. We have yet to take a long ride during such a hot day yet, as the season is winding down, it prolly wont happen this year. But glad its gone.
Might I add, I now know why I always saw Harleys riding up the side of the road during a traffic jam, and all this time I just thought they were taking advantage of the fact they had bikes
Fortunately we were travelling in proximity to my father in a car. We stopped he picked up the wife, and I continued on. A week later the cat was removed. We have yet to take a long ride during such a hot day yet, as the season is winding down, it prolly wont happen this year. But glad its gone.
Might I add, I now know why I always saw Harleys riding up the side of the road during a traffic jam, and all this time I just thought they were taking advantage of the fact they had bikes
Tourer
Joined: Sep 2006
Posts: 361
Likes: 3
From: Nashville, TN
Removed my mufflers to send to American Custom. Started the bike to put back into garage and it was so quiet you'd think the mufflers were still on. To me, that is restriction.
I now have a new catless header waiting to be put on.
I now have a new catless header waiting to be put on.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Cruiser
Joined: May 2009
Posts: 121
Likes: 1
From: Oregon
I know these discussions come up very frequently but I have to admit for those of us who sit on the fence with this issue.....every time I learn alittle more from you guys have been down the road......thanks for your patience and indulgence
Elite HDF Member
Joined: Apr 2009
Posts: 3,780
Likes: 69
From: Al Bu Ker Key, New Mexico
I think the good folks at FuelMoto posted a dyno run a while back on a bike (think it might have been a 96ci StreetGlide) with the CAT intact. The conclusion was that the CAT had NO IMPACT on freeflow and was not restrictive in any way. Correct me if I am wrong here but I think this is what I remember reading. No doubt the CAT is HOT and significantly adds to rider's discomfort. I will say however there have only been a few days here in Al Bu Ker Key where I almost had to park the bike due to heat being generated off the engine/exhaust. I still have mine but I just keep things stock in general as I find I get more trouble free miles this way.