Real Difference in Duals
Elite HDF Member
Joined: Jul 2010
Posts: 3,830
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From: Lorain Ohio
When I had my Shovel most everyone ran drag pipes, which like was stated is pretty much the same as true dual's, an the key there was the length....short drag pipes on the shovel killed low end but longer ones like 34" or 36" lowered the power band.....never read why but everyone swore that's the way it is. So....I think it might depend on what mufflers you run an how well they match your combo. I'd bet baffles are important.
Seasoned HDF Member
Joined: Dec 2005
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From: poway
That makes little sense as they all are affected the same by exhaust configuration. True duals can work great on a bagger/touring as well, BUT, there is a flatter torque curve in a good 2:1 pipe every day of the week. Many Harley stock pipes Dyna/Softail had a crossover pipe in them. That was done not for the EPA or for anything other than making the bike better to ride. Flatter torque curve for better low/mid torque. Just putting the engine in a different frame doesn't change how it is influenced by exhaust configuration.
The problem with TDs on a bagger is that the front head pipe is too long and the rear too short. You can fit staggers duals and get a good power band. It can be harder depending on the design. Pipes I mention don't have a crossover. You are thinking slipons, I'm saying complete exhaust systems.
Road Captain
Joined: Jul 2015
Posts: 565
Likes: 152
From: Calgary, Alberta
You must have a short week..
The problem with TDs on a bagger is that the front head pipe is too long and the rear too short. You can fit staggers duals and get a good power band. It can be harder depending on the design. Pipes I mention don't have a crossover. You are thinking slipons, I'm saying complete exhaust systems.
The problem with TDs on a bagger is that the front head pipe is too long and the rear too short. You can fit staggers duals and get a good power band. It can be harder depending on the design. Pipes I mention don't have a crossover. You are thinking slipons, I'm saying complete exhaust systems.
I was talking about the factory pipes and why there is a crossover pipe in those, and why you would want a crossover pipe as opposed to not having one. Just clarifying. I do know the difference between a true dual setup and anything with a crossover or collector.
Either way, run what you want. I got no dog in this hunt.
Seasoned HDF Member
Joined: Dec 2005
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From: poway
Nope, I'm certainly not thinking slipons. I'm pretty sure I know the difference. I never said that true duals or staggered duals can't produce a "good" power band. I'm only saying that a good 2:1 pipe will get you a flatter torque curve.
I was talking about the factory pipes and why there is a crossover pipe in those, and why you would want a crossover pipe as opposed to not having one. Just clarifying. I do know the difference between a true dual setup and anything with a crossover or collector.
Either way, run what you want. I got no dog in this hunt.
I was talking about the factory pipes and why there is a crossover pipe in those, and why you would want a crossover pipe as opposed to not having one. Just clarifying. I do know the difference between a true dual setup and anything with a crossover or collector.
Either way, run what you want. I got no dog in this hunt.
And you'd be wrong.
Staggered duals 640 cam.
Crossover can help but proper design of a 2-2 can be give the desired results.
Road Captain
Joined: Jul 2015
Posts: 565
Likes: 152
From: Calgary, Alberta
But, yes it is a nice curve.
Seasoned HDF Member
Joined: Dec 2005
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From: poway
What do you need to compare it to? You simply stated that that TDs won't have any low end torque.
Road Captain
Joined: Jul 2015
Posts: 565
Likes: 152
From: Calgary, Alberta
Run what you want, your choice. I still have no dog in this hunt.
Stage IV
Joined: Jun 2008
Posts: 4
Likes: 0
From: Colorado
I put MGS true duals on my 2008 streetglide a few years ago and tuned my tts tuner. I can honestly say I lost no torque at all. Bike pulls better then it did originally. Good tune and stepped true duals worked for me. I personally think 2 into 1 exhaust sounds like crap. Just me maybe !!
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Joe Kucinski
Seasoned HDF Member
Joined: Dec 2005
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From: poway
Incorrect. I only said you'd do better with a 2:1. Please, let's not start misrepresenting what each has said. If I'm wrong, then I'm wrong ... it's happened before, will happen again, but I never said "TDs won't have any low end torque".
Run what you want, your choice. I still have no dog in this hunt.
Run what you want, your choice. I still have no dog in this hunt.
Yeah you're right.. That one I don't have a direct comparison. This one is close. Lower power was a thunderheader compared to staggered duals. The staggered duals did have a small 1 inch cross over at the muffler. You got any runs to show otherwise?
Road Captain
Joined: Jul 2015
Posts: 565
Likes: 152
From: Calgary, Alberta
I put MGS true duals on my 2008 streetglide a few years ago and tuned my tts tuner. I can honestly say I lost no torque at all. Bike pulls better then it did originally. Good tune and stepped true duals worked for me. I personally think 2 into 1 exhaust sounds like crap. Just me maybe !!