Why "true duals"
Stellar HDF Member
Joined: Jun 2007
Posts: 2,928
Likes: 117
From: Ashby, Ma
With True Duals there is no scavenging effect where the exiting exhaust of the previous cylinder firing pulls the exhaust from the current firing cylinder. This is why 2-into-1 are the best performers.
Bottom line, true duals are not a benefit for most of us, because we run lower rpm ranges as we cruise/tour. Now, if you're above 3.5K on the tach a lot, they may be a benefit.
Road Captain
Joined: Jan 2013
Posts: 576
Likes: 20
From: Eau Claire, WI
Fact of the matter is, unless you just want to have every bit of performance you can get, ANY after market pipes with a high flow air cleaner are going to be better than the stock setup, and sound better to, assuming you want more sound. If you like the look and sound of true duals, then get em. if not, don't. literally that damn simple. People are gonna argue all day long, with the vast majority not havin a damn clue what the hell they're even talking about. Truth of it is, 90 percent of the time you ask a question like this, what you're gonna get is everybody tellin you what they have is the best. I have a 2000 road king with a bone stock motor with the exception of vance and hines slipons and a forcewinder intake with a K&N filter, and i've never once been pissed off about not having enough power.
Road Master
Joined: Aug 2012
Posts: 944
Likes: 2
From: Ct
You lose a little torque and hp when you go with Duals over a 2 into 1 UNLESS you get some stepped high performance true duals that are out there and compare them to a poor performing 2 into 1.
generally speaking a 2 into 1 will perform better than true duals.
I have always run true duals, I ran rinehardts I love the look and sound, but this time I am going with a 2 into 1 technically, it is actually two short head pipes that terminate in a small collector on one side of the bike.
I went this way because after riding 2 up with bags full and the bike loaded I needed more torque when traveling especially for passing but even riding big hills, or taking off on a hill fully loaded even with the 103 I need more.
I dont wan t start with cams and beyond, I want to get my gains in a good stage one so I need to count every extra bit I can get to be satisfied.
I will tell ya in 4 days when they arrive and I tune the bike and install everything.
Also I decided in time I am going to do a set of stretch bags I really like a lot and there arent any true dual pipes that are going to easily work with them so I went this route, personally I think they look better and they definitely perform better from everything I have seen and everyone using them I have talked to.
Lump
generally speaking a 2 into 1 will perform better than true duals.
I have always run true duals, I ran rinehardts I love the look and sound, but this time I am going with a 2 into 1 technically, it is actually two short head pipes that terminate in a small collector on one side of the bike.
I went this way because after riding 2 up with bags full and the bike loaded I needed more torque when traveling especially for passing but even riding big hills, or taking off on a hill fully loaded even with the 103 I need more.
I dont wan t start with cams and beyond, I want to get my gains in a good stage one so I need to count every extra bit I can get to be satisfied.
I will tell ya in 4 days when they arrive and I tune the bike and install everything.
Also I decided in time I am going to do a set of stretch bags I really like a lot and there arent any true dual pipes that are going to easily work with them so I went this route, personally I think they look better and they definitely perform better from everything I have seen and everyone using them I have talked to.
Lump
Last edited by lumper; May 31, 2013 at 09:07 PM.
Grand HDF Member
Joined: Sep 2009
Posts: 3,808
Likes: 285
From: Green Country Oklahoma
True dual is such a simple and whole lot cheaper design vs stock if that is the answer for a better performing motor Harley will go for any cheaper supplier instead of the complicated and too many pieces stock system.
Banned
Joined: Sep 2005
Posts: 4,341
Likes: 0
From: Dover, Oh
WTF did you say????
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
He said true duals are a simpler design and cheaper to manufacture. If they really worked Harley would adopt this system to reduce manufacturing costs. He is correct.
Road Captain
Joined: Apr 2010
Posts: 671
Likes: 159
If you pay a grand for true duals over any other exhaust you got ripped off.
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Banned
Joined: Sep 2005
Posts: 4,341
Likes: 0
From: Dover, Oh
It's not correct, hd has used a couple of the biggest names in the exhaust business. They are after controlling emissions..... That's it!
