Pros/cons with true Duals vs. 2 into 1 into 2 .

 

Lots of folks like the sound and/or look of true duals but a good 2-1-2 will outperform a good true dual set-up on a bagger. Hell a stock non-cat '09 header will outperform a good true dual set-up on a bagger.

 

a.) one of the advantages of a 2/1/2 set up is the large volume of the exhaust system.

the same twin cam A motor is used in the Touring and Dyna frames- the touring will always show about 3 horsepower more...the only diff is the exhaust system.
the large volume allows for high exhaust gas velocity

b.) another is that when the cylinders exhausts are connected as the exhaust gasses rush down the pipe, they form a low pressure zone behind them...this can "suck" the exhaust gasses out of the other cylinder faster.
which in turn can "suck" the intake charge of air and fuel into the cylinder faster- it is possible to get a more than 100% cylinder fill.
this is known as scavenging and it's effect is much dependent on cam profile

( this is why the v8 in the driveway has carefully designed headers and an "X" pipe by the transmission connecting the 2 cylinder banks...free power with out extra emissions or fuel consumption)


some riders prefer the sound of true duals, feel it gives better heat control or somehow has a "traditional look".

some of us with "traditional bikes" have the stock 2 into 1



mike

 

Subscribed. I have a stock head pipe, and hate the look. I believe there's a performance advantage in the 2-1-2, but in reality I'm not going racing and horsepower gains aren't as important to me as style is.

 

true duals look and sound better , IMO , if your not into the big power thing that's the way to go , mine runs just fine

 

I went with the V&H Bagger Duals and the monster rounds on my '12 FLTRX. I am also running the SE255 cams. I am at 98 ft/lbs and 88HP with the Ventialtor (sp?) air filter on a 103" everything Ive seen shows that I am about 4HP down and about even on torque on other bikes with a 2-1 or 2-1-1.

Im good with the power where its at.

 

I had used either Rinehart true duals or Vance & Hines dresser duals on my touring bikes for years, but I went with a set of the Vance & Hines power duals on my new 2014 Limited and I've been really impressed. They give more power by having the crossover chamber, but retain a lot of the look of true duals and still sound like true duals.

 

I have the Vance & Hines Power Duals Head Pipes and Vance & Hines High Flo mufflers. Compared to stock ... ya big difference.

Power Duals is the ticket to style, quality and performance
More than just individual head pipes, Power Duals integrates an exclusive Vance & Hines Power Chamber hidden behind a contoured heat shield that generates more horsepower and torque than stock
This new right side design eliminates the heat issues on the left side for the passenger, routing hot exhaust gases below the footpeg and protecting vital engine components and side covers from heat damage
Allows the use of any many muffler options
Made in the U.S.A.!!!
Plus they look damn cool IMHO

 

nice cut and paste!

mike

 

Is that frowned upon? It was from their site. Since I own them and agree I thought it was ok to CUT & PASTE.