duals
Road Captain
Joined: Feb 2009
Posts: 671
Likes: 5
From: D.C suburbs
I went supertrapp to MGS, I did notice the difference but it wasn't bad. You can feel it though, mostly torque loss. If you went from stock pipes u probably won't notice a change. My loss has been even bigger when I added 107 and heads, not producing as much as I think they should. I am putting it on the dyno soon to see how much i am loosing. They sound mean with the big build and that's my trade off
Tourer
Joined: Oct 2012
Posts: 336
Likes: 1
From: Senoia Ga
2. It's more the case that bringing the pipes together provides a bonus! If you look at any recent Buell they have equal length pipes, which may look ugly, but they enable the designer to increase CR and use much wilder cams, giving more power and torque, while still meeting the same EPA regulations as all Harleys.
With a near stock Harley, power for TDs will be similar to any of the siamesed systems, but torque will be improved. I ran TDs on the bike in my sig pic for a while, before swapping to the Supermeg you see and had both set up on the dyno by the same shop.
Headline numbers were similar, with the 2-into-1 giving a little more peak torque, however the low/mid range torque was up to 15% higher with the Supermeg. In addition the engine is far smoother and just a lot nicer to ride. So there is more to the difference than meets the eye!
3. I never used stock headers with this S&S 107" engine, but no way will I go back to TDs.
4. I would expect your stock pipes, with suitable mufflers, to give better results than any TDs.
With a near stock Harley, power for TDs will be similar to any of the siamesed systems, but torque will be improved. I ran TDs on the bike in my sig pic for a while, before swapping to the Supermeg you see and had both set up on the dyno by the same shop.
Headline numbers were similar, with the 2-into-1 giving a little more peak torque, however the low/mid range torque was up to 15% higher with the Supermeg. In addition the engine is far smoother and just a lot nicer to ride. So there is more to the difference than meets the eye!
3. I never used stock headers with this S&S 107" engine, but no way will I go back to TDs.
4. I would expect your stock pipes, with suitable mufflers, to give better results than any TDs.
Are those Supermegs on the bike in your sig pic?. If not what exhaust is that? The reason I'm asking is that my wife complains bitterly about the heat on the right side. And she is correct... it is extremely hot... I think it is is from that rear exhaust pipe. I think I see that they turn left and come out the left side. If that is the case I'M VERY interested in that exhaust. Reguardless of the performance.
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
Are those Supermegs on the bike in your sig pic?. If not what exhaust is that? The reason I'm asking is that my wife complains bitterly about the heat on the right side. And she is correct... it is extremely hot... I think it is is from that rear exhaust pipe. I think I see that they turn left and come out the left side. If that is the case I'M VERY interested in that exhaust. Reguardless of the performance.
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
I changed my sigpic recently and that is an earlier shot of my bike with true duals. Sorry about that. THIS is the photo I should have posted, with the SuperMegs:
Road Warrior
Joined: May 2012
Posts: 1,570
Likes: 117
From: Southeast NC
i agree 100% and then some. Im getting there x pipe soon. far superior to true duals and with ceramic coating the heat is cut down even more. My buddy has em and they are sweet. You actually gain power and torque. no brainer for me
I am not disagreeing.
However, I would like to see a before/after dyno sheet, going from TRUE duals to whatever 2/1/2 a man chooses, with no changes other than exhaust, and of course, the accompanying proper tune.
I'm willing to bet lunch that the numbers are not mind blowing... and really not enough to feel on a daily rider.
Might see a few thousandths on the track, but I've never been there.
However, I would like to see a before/after dyno sheet, going from TRUE duals to whatever 2/1/2 a man chooses, with no changes other than exhaust, and of course, the accompanying proper tune.
I'm willing to bet lunch that the numbers are not mind blowing... and really not enough to feel on a daily rider.
Might see a few thousandths on the track, but I've never been there.
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Seasoned HDF Member
Joined: Jan 2013
Posts: 10,637
Likes: 1,246
From: Lake, Ms
I am not disagreeing. However, I would like to see a before/after dyno sheet, going from TRUE duals to whatever 2/1/2 a man chooses, with no changes other than exhaust, and of course, the accompanying proper tune. I'm willing to bet lunch that the numbers are not mind blowing... and really not enough to feel on a daily rider. Might see a few thousandths on the track, but I've never been there.
2010 Limited with some stuff
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
True duals are simply drag pipes with mufflers. The pipes also have the disadvantage of not being the same length, so they are not off to a good start! I enjoyed mine for several years and only changed to a 2-into-1 because of problems keeping the left-hand pipe off the primary casing. I've already referred to the benefits, measured on the same dyno, of my current system over my TDs, in post #6. It's the only way to travel!
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