Why "true duals"
Road Warrior
Joined: Dec 2008
Posts: 1,250
Likes: 0
From: París, TX
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.
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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.
Attachment 317782
Lump
Outstanding HDF Member
Joined: Mar 2009
Posts: 2,216
Likes: 102
From: Central Illinois
Last year I changed my stock system over to Fullsac true duals. Used the same mufflers and the sound was much better. I didn't think I lost any low end, but when it was good and hot and taking off from a stop, it acted like it was in too high of a gear. I did, however, have a persistent leak I could not effectively find for awhile but turned out to be where the rear Fullsac pipe slipped into the stock pipe. Could not get it to stop leaking so junked the whole system.
I went with the V&H Pro Pipe 2 into 1 and immediately noticed a much better sound, less annoying too. No leaks and best of all, it performs waaaay better than the true duals. Feels like another bike. I am much happier with this system and I have much less heat on my legs than the stock or true duals also. With the true duals my left leg got a lot hotter than before.
I went with the V&H Pro Pipe 2 into 1 and immediately noticed a much better sound, less annoying too. No leaks and best of all, it performs waaaay better than the true duals. Feels like another bike. I am much happier with this system and I have much less heat on my legs than the stock or true duals also. With the true duals my left leg got a lot hotter than before.
Banned
Joined: Sep 2005
Posts: 4,341
Likes: 0
From: Dover, Oh
I love when people say true duals looses power down low. Over a properly tuned two into one yes you might. Over stock I still gained on every bike I have but true duals one. Never a loss down low. The upper rpm gain was even better!
Most people have never dynoed back to back runs and just pass on Internet info and their "seat of the pants" justification for false info.
My 06 street glide would out run any equally equipped big three modded bike. Everyone swore I must have had cams.
Most people have never dynoed back to back runs and just pass on Internet info and their "seat of the pants" justification for false info.
My 06 street glide would out run any equally equipped big three modded bike. Everyone swore I must have had cams.
Grand HDF Member
Joined: Sep 2009
Posts: 3,808
Likes: 285
From: Green Country Oklahoma
WTF you didn't understand may be you need to put both especially rear stock header pipe next to TD one and do some thinking then it might make a sense to you and count how many extra pieces and extra clamps and get a calculator to figure the cost.
Grand HDF Member
Joined: Sep 2009
Posts: 3,808
Likes: 285
From: Green Country Oklahoma
Thank you for backing me up I think he is not familiar with TD design I have both of em and it clearly makes a sense.
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Grand HDF Member
Joined: Sep 2009
Posts: 3,808
Likes: 285
From: Green Country Oklahoma
Until newer cat header pipes emission was controlled by slipons so Harley would have save millions by using TD IMO.
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
This is loss of low end torque. They all do it, no matter the crowd that has spent a small fortune making their bike perform worse says. It is pretty noticeable in sixth gear too.