2 into 1 vs. Tru Dual
Tourer
Joined: Jan 2006
Posts: 373
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From:
RE: 2 into 1 vs. Tru Dual
I swear I just saw an advertisement somewhere for a 2:1 exhaust with a 2nd "dummy" pipe for the other side of the bike. But I agree, if it's an improvement in the 1-2k rpm range, where would one realistically see that improvement? You'd be going 35 in 5th I guess, at less than 20% throttle.
Outstanding HDF Member
Joined: Jan 2006
Posts: 3,249
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From: Lubbock, TX
RE: 2 into 1 vs. Tru Dual
I know D&D makes what they call a "Ghost Pipe" for dressers. It is about $250-300.
ORIGINAL: OG_electra_glide
I swear I just saw an advertisement somewhere for a 2:1 exhaust with a 2nd "dummy" pipe for the other side of the bike. But I agree, if it's an improvement in the 1-2k rpm range, where would one realistically see that improvement? You'd be going 35 in 5th I guess, at less than 20% throttle.
I swear I just saw an advertisement somewhere for a 2:1 exhaust with a 2nd "dummy" pipe for the other side of the bike. But I agree, if it's an improvement in the 1-2k rpm range, where would one realistically see that improvement? You'd be going 35 in 5th I guess, at less than 20% throttle.
Stage II
Joined: May 2011
Posts: 2
Likes: 0
SE to True Duals
Be prepared with a SERT and a good Dyno run. I made the switch and my bike ran really bad until I went to the SERT and it was on the Dyno for a while. Now with my V&H True Duals and bike tuned right they are the best investment I've made. Put 103 behind them and they are loud and sound fantastic...
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
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From: SoCal
I swear I just saw an advertisement somewhere for a 2:1 exhaust with a 2nd "dummy" pipe for the other side of the bike. But I agree, if it's an improvement in the 1-2k rpm range, where would one realistically see that improvement? You'd be going 35 in 5th I guess, at less than 20% throttle.
Road Warrior
Joined: Mar 2010
Posts: 1,980
Likes: 16
From: USA
I'll chime in.....
All of my life I hated the look of 2-1's and especially on baggers. But, it's grown on me after I purchased this last bike which came stock 2-1. So, that's the look I kept when I upgraded. I like it. And from the numbers I've seen, you're getting good numbers at the bottom and top ends.
All of my life I hated the look of 2-1's and especially on baggers. But, it's grown on me after I purchased this last bike which came stock 2-1. So, that's the look I kept when I upgraded. I like it. And from the numbers I've seen, you're getting good numbers at the bottom and top ends.
Road Warrior
Joined: Aug 2010
Posts: 1,788
Likes: 5
From: Tennessee
I did on my sig bike. The difference is goin from bein the slowest bike in the pack to beatin stock 103s. I had a 2into1 and you definately notice more off-idle power. But unless you have a riding deficiency and tend to fall over at stoplights true duals are the way to go. IMO
Too many variables to make a generalization. Properly designed 2-1 systems with a merge collector (like a fatcat or propipe) will generally make a bit more at the lower rpms, due to increased exhaust scavenging. As rpms and exhaust gas speeds rise, the scavenging effect from the opposite cylinder has less of an effect, and overall exhaust volume becomes more important, and that's where the good TD systems start to gain an advantage. The tune is crucial. The best exhaust in the world won't overcome a poor tune, but a good tune can compensate for all kinds of exhaust variations.
Your definition of best performing might be different than another guys. Some want the most power, peak torque and hp, others focus more on early torque production.
Here's a chart showing two identical bikes, exactly the same except for the exhaust. The one with the fatcat 2-1 has an earlier torque curve, the one with the Rinehart TDs has higher overall numbers. Running around town, the fatcat bike will feel a little snappier, but in a race, the one with the TDs would likely pull away.
Here's another chart comparing the fatcat with the Rinehart TDs. Similar looking curves. Again, up to about 3K rpms, the fatcat comes on earlier, but the Rineharts post higher numbers. Some guys want the early torque curve and don't care about overall numbers, others want the most power they can get.
Your definition of best performing might be different than another guys. Some want the most power, peak torque and hp, others focus more on early torque production.
Here's a chart showing two identical bikes, exactly the same except for the exhaust. The one with the fatcat 2-1 has an earlier torque curve, the one with the Rinehart TDs has higher overall numbers. Running around town, the fatcat bike will feel a little snappier, but in a race, the one with the TDs would likely pull away.
Here's another chart comparing the fatcat with the Rinehart TDs. Similar looking curves. Again, up to about 3K rpms, the fatcat comes on earlier, but the Rineharts post higher numbers. Some guys want the early torque curve and don't care about overall numbers, others want the most power they can get.
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Joe Kucinski
Ultimate HDF Member
Joined: May 2008
Posts: 7,439
Likes: 884
From: 'Noke, VA
I've recently changed from a Fatcat to a 2:1:2. There's no doubt in my mind that the Fatcat makes more power everywhere. TDs are going to be an even larger difference, especially down low.
Boogaloodude, any tuner worth his salt can tune away that horrendous torque dip on the Fatcat.
Last edited by '05Train; May 23, 2011 at 07:05 PM.
