Whats downside running w/o baffles?
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
aside from hate & meeting lots of cops ( your NJ troopers have the silliest caps...)
a "suddenly open" exhaust system will result in lower exhaust gas velocity- the gasses don't leave as quickly, may even eddy and reverse direction inside the pipes
these muddled up gasses then affect the following cycle.
quickly exiting exhaust gasses will form a low pressure zone behind them which helps to pull the next intake charge into the cylinder- so you get more air ( and can add more fuel) for a bigger burn and more power per cycle.
Exhaust system design and tuning is difficult, but when done right can extract "free power" in an rpm range where we actually run the bikes. ( straight pipes are proven the give power gains at 6000 rpms +)
you may have noticed that a small import car with a 4" exhaust will seem to rev forever just to leave a stop sign... too large an exhaust, too large an intake will negatively affect performance
one of the loudest bikes i ever, ever heard was a dyna with some kinda megaphone straight pipes at a swap meet...as we got to the freeway onramp, he just sat in front of me blatting away, trying to slip the clutch to get started...I went around him and continued on at a normal speed, he never caught up to me over the next 6 miles...I was riding one of my '53's stock...38 horsepower.
mike
a "suddenly open" exhaust system will result in lower exhaust gas velocity- the gasses don't leave as quickly, may even eddy and reverse direction inside the pipes
these muddled up gasses then affect the following cycle.
quickly exiting exhaust gasses will form a low pressure zone behind them which helps to pull the next intake charge into the cylinder- so you get more air ( and can add more fuel) for a bigger burn and more power per cycle.
Exhaust system design and tuning is difficult, but when done right can extract "free power" in an rpm range where we actually run the bikes. ( straight pipes are proven the give power gains at 6000 rpms +)
you may have noticed that a small import car with a 4" exhaust will seem to rev forever just to leave a stop sign... too large an exhaust, too large an intake will negatively affect performance
one of the loudest bikes i ever, ever heard was a dyna with some kinda megaphone straight pipes at a swap meet...as we got to the freeway onramp, he just sat in front of me blatting away, trying to slip the clutch to get started...I went around him and continued on at a normal speed, he never caught up to me over the next 6 miles...I was riding one of my '53's stock...38 horsepower.
mike
Last edited by mkguitar; Nov 17, 2013 at 01:49 PM.
Tourer
Joined: Oct 2012
Posts: 336
Likes: 1
From: Senoia Ga
You know Mike, I usually agree with you ...And this is a minor exception. On the 09's at least. On the bikes with the cats in the head pipe ,,,I can't say, Anyway I had a fuel pac and and a airfilter with an V&H exhaust on my 09 ultra.( My fuel pac is for sale by the way, in the classifieds) I ran it with the baffeles. Did well, Then I took out the baffels I had a dead spot in my throttle.
Sounded GREAT but a pronounced dead spot. Then I bought the ThunderMax. NO more dead spots. No more throttle lag.
Maybe the cobra system can do this IDK!
Sounded GREAT but a pronounced dead spot. Then I bought the ThunderMax. NO more dead spots. No more throttle lag.
Maybe the cobra system can do this IDK!
Last edited by Hogster 1; Nov 16, 2013 at 07:39 PM.
Outstanding HDF Member
Joined: Nov 2013
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From: Indiana
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Tourer
Joined: Sep 2006
Posts: 266
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From: LI, NY
I agree
Totally obnoxious, why ruin it for everyone else
Totally obnoxious, why ruin it for everyone else
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Road Warrior
Joined: Aug 2008
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From: Michigan
What's the point? If you think its cool your wrong. You are the person that gives the sport a bad name.
Oh, I know you are one of many who could careless but really? You are the kind of guy I would like to go up to and slap too the ground till you cry like a baby but it would only result in something bad for both of us especially me so I just grin and bare it in hopes you will grow up and see how stupid you were.
Oh, I know you are one of many who could careless but really? You are the kind of guy I would like to go up to and slap too the ground till you cry like a baby but it would only result in something bad for both of us especially me so I just grin and bare it in hopes you will grow up and see how stupid you were.
Thread Starter
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Cruiser
Joined: Mar 2013
Posts: 201
Likes: 4
From: newark
What's the point? If you think its cool your wrong. You are the person that gives the sport a bad name.
Oh, I know you are one of many who could careless but really? You are the kind of guy I would like to go up to and slap too the ground till you cry like a baby but it would only result in something bad for both of us especially me so I just grin and bare it in hopes you will grow up and see how stupid you were.
Oh, I know you are one of many who could careless but really? You are the kind of guy I would like to go up to and slap too the ground till you cry like a baby but it would only result in something bad for both of us especially me so I just grin and bare it in hopes you will grow up and see how stupid you were.
