Thoughts on Cat being restrictive......
Outstanding HDF Member
Joined: Jan 2010
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From: earth
"shakin' the bush Boss"
Tourer
Joined: May 2009
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From: Dunstable, MA
+1 on the cat is not a restriction, just a noise suppressor, and heat source.
Ultimate HDF Member
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From: Jayhawk Country
Very doubtful, here's a dyno sheet from their website showing the gains on a stock bike with just the addition of their head pipe. Dont get me wrong, I think their pipe is great but not for $450. That's around $100 per 1 hp. I cant justify that kind of money for the gains but it's not just their head pipe, it's all of them unless you go 2 into 1.
Last edited by KCFLHRC; Aug 15, 2011 at 09:56 AM.
Road Master
Joined: Jun 2006
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From: Jaw-Jaw (Near The BIG Chicken!)
Seat of the pants, I'm VERY happy... Seat of the pants - a cheap dyno. LOL!!!
Cruiser
Joined: Jul 2011
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From: PA
No, the fact that the cat is hot is due to the fact that it oxidizes (burns) unburnt hydrocarbon and carbon monoxide molecules in the exhaust.
Tourer
Joined: Jul 2008
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From: Mass.
Why do so many here seem to feel that if a decatted pipe shows no power gains on a dyno , that it proves it isnt a restriction ?? Who ever said that less backpressure always has to equal an increase in hp and/or torque ???
From my experience and posts in other threads , I never said that I noticed actual power gains. Frankly if I didn't have the heat issue, I never would have bothered removing the cat ...and I really didn't want the volume increase... But be that as it may , to me there was an obvious night and day difference in the amount of backpressure during acceleration and deceleration .
From my experience and posts in other threads , I never said that I noticed actual power gains. Frankly if I didn't have the heat issue, I never would have bothered removing the cat ...and I really didn't want the volume increase... But be that as it may , to me there was an obvious night and day difference in the amount of backpressure during acceleration and deceleration .
Last edited by Tele00; Aug 15, 2011 at 10:44 AM.
You can buy all the heat deflectors you want and they will still not give you the heat relief that removing the cat will. You would have to buy one that hangs down past the passangers foot rests to do any good. The wife is very happy by not having her feet burned off when we go riding. When Mama's happy, everybody's happy.
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Tourer
Joined: Apr 2006
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You can buy all the heat deflectors you want and they will still not give you the heat relief that removing the cat will. You would have to buy one that hangs down past the passangers foot rests to do any good. The wife is very happy by not having her feet burned off when we go riding. When Mama's happy, everybody's happy.
Performance gains/issues, back pressure, and exhaust noise/tone/loudness aside...my right foot, ankle, shin, and calf all told me it was better without that CAT riding with them.
Extreme HDF Member
Joined: Dec 2007
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From: Illinois
Because it is in your head. Many others as I did could not detect any change at all with removing the cat. The cat has virtually no back pressure and removing it changes nothing except less heat.
The exhaust may be a little cooler and therefore denser which could account for the change your super sensitive ears are hearing.
The exhaust may be a little cooler and therefore denser which could account for the change your super sensitive ears are hearing.