Back pressure...I'm confused
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Tourer
Joined: Nov 2007
Posts: 441
Likes: 0
From: Brentwood, Tennessee
Back pressure...I'm confused
I've been caught up in the on going discussion about changing over to true duals, and the controversy about the loss of torque caused by the loss of back pressure when true duals are installed on a bagger. If the back pressure/torque gain is so significant with stock bagger pipes, then why don't owners of Dynas, Soft Tails & Sportys change over to the system that the MOCO puts on baggers as stock equipment? Wouldn't they gain from such a change over?
Bottom line is, are we baggers making a big deal over nothing, or are the owners of the "other" Harleys missing out?
Bottom line is, are we baggers making a big deal over nothing, or are the owners of the "other" Harleys missing out?
Road Master
Joined: Aug 2006
Posts: 1,038
Likes: 26
From: Fort Worth, Texas
RE: Back pressure...I'm confused
Not so much on bacpressure as it is more on scavaging. The stock dyna and softails have this small crossover tube between exhaust that helps. Not sure if the stock sporties have this crossover pipe but I am sure the do. It is removed when drag pipes or most any aftermarket pipe is installed With a slip on pipe, the crossover stays. So it is in some sort the same as the bagger system.
Outstanding HDF Member
Joined: Jul 2007
Posts: 2,424
Likes: 0
From: Hoboken, New Jersey
RE: Back pressure...I'm confused
Here is some good info re: back pressure
Here is some more I dont know how accurate it is though...I didnt read it all.
Here is some more I dont know how accurate it is though...I didnt read it all.
Road Master
Joined: Oct 2007
Posts: 813
Likes: 1
From: REPUBLIC of TEXAS
RE: Back pressure...I'm confused
Road Warrior
Joined: Dec 2006
Posts: 1,530
Likes: 0
From: Diamond Bar, California
RE: Back pressure...I'm confused
ORIGINAL: BOARGAURD
Not so much on bacpressure as it is more on scavaging. The stock dyna and softails have this small crossover tube between exhaust that helps. Not sure if the stock sporties have this crossover pipe but I am sure the do. It is removed when drag pipes or most any aftermarket pipe is installed With a slip on pipe, the crossover stays. So it is in some sort the same as the bagger system.
Not so much on bacpressure as it is more on scavaging. The stock dyna and softails have this small crossover tube between exhaust that helps. Not sure if the stock sporties have this crossover pipe but I am sure the do. It is removed when drag pipes or most any aftermarket pipe is installed With a slip on pipe, the crossover stays. So it is in some sort the same as the bagger system.
the Dynas and Softys are lighter and the effects of a true dual or drag pipe style pipe are deminished on these bikes. and alot of people cam there bikes bigger and have alot more compresion with these bikes, so tuning is different.
Road Warrior
Joined: Oct 2007
Posts: 1,446
Likes: 5
From: Chicago, IL.
RE: Back pressure...I'm confused
My opinion is unless your racing the bike it is not a very significant difference any way you go.
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Extreme HDF Member
Joined: Apr 2006
Posts: 10,449
Likes: 46
From: Roswell, GA
RE: Back pressure...I'm confused
My butt dyno isn't sensitive enough to notice a difference; I did Rinehart TD's and an SE a/c at the same time, but I couldn't tell you that right off idle there was any difference; above 2000 or so there was a big improvement, however.
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Grand HDF Member
Joined: Feb 2005
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From: Twin Cities Minnesota
RE: Back pressure...I'm confused
ORIGINAL: pab
I've been caught up in the on going discussion about changing over to true duals, and the controversy about the loss of torque caused by the loss of back pressure when true duals are installed on a bagger. If the back pressure/torque gain is so significant with stock bagger pipes, then why don't owners of Dynas, Soft Tails & Sportys change over to the system that the MOCO puts on baggers as stock equipment? Wouldn't they gain from such a change over?
Bottom line is, are we baggers making a big deal over nothing, or are the owners of the "other" Harleys missing out?
I've been caught up in the on going discussion about changing over to true duals, and the controversy about the loss of torque caused by the loss of back pressure when true duals are installed on a bagger. If the back pressure/torque gain is so significant with stock bagger pipes, then why don't owners of Dynas, Soft Tails & Sportys change over to the system that the MOCO puts on baggers as stock equipment? Wouldn't they gain from such a change over?
Bottom line is, are we baggers making a big deal over nothing, or are the owners of the "other" Harleys missing out?
LOOKS, is why they don't change on Sporty's etc. Not performance.
