Cats and decibels
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Joined: Aug 2008
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From: Northern Nevada
Cats and decibels
How much does the cat affect the loudness of an exhaust system?
I installed a set of Monster Ovals, keeping the stock headers on my '09 RK. Though I'm satisfied with the quality, looks and tone of the pipes, they are just too quiet. I've gotten mixed opinions from two dealers and two shops. One dealer and one shop say I should see a significant increase in volume by installing aftermarket headers, and the other two say no significant increase. I'd appreciate opinions from those with experience in this.
I'm thinking of just replacing the Ovals with louder slipons, but if a set of headers will fire up the Ovals, I'd rather go that way.
I installed a set of Monster Ovals, keeping the stock headers on my '09 RK. Though I'm satisfied with the quality, looks and tone of the pipes, they are just too quiet. I've gotten mixed opinions from two dealers and two shops. One dealer and one shop say I should see a significant increase in volume by installing aftermarket headers, and the other two say no significant increase. I'd appreciate opinions from those with experience in this.
I'm thinking of just replacing the Ovals with louder slipons, but if a set of headers will fire up the Ovals, I'd rather go that way.
Road Warrior
Joined: Sep 2008
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From: North Texas
A TON. Buddy has a 2010 SE SG and put rinehart mufflers on, it sounded like a HondaSaki. Put true duels on without a cat, sounds like a Harley now. Made a HUGE difference.
Here's a picture of one, see for yourself how much restriction there is.
Here's a picture of one, see for yourself how much restriction there is.
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From: Northern Nevada
Thanks.
Are all cats located in the crossover?
Road Warrior
Joined: Sep 2008
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From: North Texas
Damn! That photo scared me half to death. Why would the Carson City dealer tell me "no significant increase in volume" if it's as obvious as that photo shows? (I can think of an obvious answer, but I'll give him the benefit of the doubt for now.)
Thanks.
Are all cats located in the crossover?
Thanks.
Are all cats located in the crossover?
Trust me, it will make a huge difference and will really wake your exhaust up.
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Joined: Aug 2008
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From: Northern Nevada
(Carson City, Nevada. FWIU, California dealers can't even do mods to an exhaust system. That brings a lot of work to dealers and shops in Reno/Carson City.)
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From: Hesperia CA
I put 4" SE slip-ons my 2009 UltraGlide, and it made a little bit more noise, but not enough for me. I pulled the baffles out and did not like what I saw. I made a pair of my own baffles out of 2" stock pipe and a design I found of another web site. Got more sound, and a lot more power.
I then purchased a stock head pipe off a 2009 SE w/cat that a HD sold on ebay (new take off) for $60 (sell at HD for over $400), cut it in half, and removed the cat material, and welded back together. I live in California, so if they enact the emmission inspection in future, I can put the stock pipe back on.
POW!!! To much sound now. Put the stock SE baffles back in the pipes, re-mapped my PCV, and sound like a real harley now.
That cat really F's up the sound, and causes the heads to heat up more.
Ride on...
I then purchased a stock head pipe off a 2009 SE w/cat that a HD sold on ebay (new take off) for $60 (sell at HD for over $400), cut it in half, and removed the cat material, and welded back together. I live in California, so if they enact the emmission inspection in future, I can put the stock pipe back on.
POW!!! To much sound now. Put the stock SE baffles back in the pipes, re-mapped my PCV, and sound like a real harley now.
That cat really F's up the sound, and causes the heads to heat up more.
Ride on...
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Road Warrior
Joined: Sep 2008
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From: North Texas
Hell, I wouldn't be surprised if there's a report that comes out in a year or two that talk about damage due to the constriction caused by the cat. I don't see how the motor is breathing at all with that thing in there.
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Tourer
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I'm not sure you would like it, as it would be a can with an end-cap as there is no baffle in the nightstick. One of the Supertrapp wrenches was asked that question on their tech forum and advised against it. He said it was designed in conjunction with the cats, thus no baffle of any sort in the muffler body.