Change the head pipe or not
Seasoned HDF Member
Joined: Apr 2012
Posts: 9,980
Likes: 5,218
From: Michigan
Getting rid of the "cat" either by gutting the pipe, or replacing it is the best thing that you can do for your engine.
I'm not a "performance" guy by any means but getting rid of the heat that is produced by the catalytic converter is hard on the engine.
I'm not a "performance" guy by any means but getting rid of the heat that is produced by the catalytic converter is hard on the engine.
MODERATOR
Joined: Oct 2007
Posts: 4,108
Likes: 1,964
From: New England
IIRC, the cat on these bikes is located in the exhaust pipe well behind the engine.
Elite HDF Member
Joined: Jul 2008
Posts: 3,524
Likes: 34
From: Maryland
Whatever you do don't do nothing. Gut it to remove cat or buy a new head pipe.
Back pressure and heat.
Back pressure and heat.
Ultimate HDF Member
Joined: Mar 2012
Posts: 6,129
Likes: 143
From: Santa Cruz
Contrary to popular myth the CAT does not increase back pressure or engine temperature. It does decrease exhaust noise and increase exhaust heat. Completely different things. That said, a properly designed header can increase performance over the stock exhaust.
Intermediate
Joined: Aug 2010
Posts: 36
Likes: 0
From: Tennessee
i will tell you that on my bike i replaced the head pipe and did a stage one it really reduced the heat that was terrible, seems to have more power but may just be the sound, i am still running the stock pipes i think it sounds good.
Road Captain
Joined: Nov 2011
Posts: 547
Likes: 0
From: Illinois Corn Desert
Decat, save your money. Reduces heat. It does open up the flow. Anything in the path of flow is restriction, maybe not severe or performance robbing restriction but anything in the path of flow is restrictive. Read "decatting debate continues" thread. Make up your own mind.
Road Captain
Joined: Nov 2011
Posts: 547
Likes: 0
From: Illinois Corn Desert
Correct, the cat does not create anything or reduce to any appreciable degree flow enough to cause backpressure....BUT.....the presence of the cat does trap heat in that area just by the physical nature of it mass and position. Remove and it will reduce perceived heat levels especially for your passenger.
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Road Captain
Joined: Nov 2011
Posts: 547
Likes: 0
From: Illinois Corn Desert
Road Warrior
Joined: Mar 2009
Posts: 1,614
Likes: 27
From: Toms River, NJ
I don't ride fast. The stock bike is fast enough for me. I ride two up and the cat was very hot after awhile on the wife's right foot/ ankle. I changed to the V&H Power Duel and V&H Monster Ovals, SE back plate, K&N A/C and the PC V. Bike runs much cooler, sounds great and not too loud. As far as dino runs and HP gains, I can't comment but removing the CAT was the best move I made.
Be Safe JIM
Be Safe JIM