True dual question
I always thought this was an area of unnecessary compromise for HD. The '08 and earlier suffered from extreme heat for the passenger and less then optimal flow due to the hard left turn the exhaust gasses make immediately when leaving the combustion chamber. On '09 and newer, the linguini shaped section of pipe under the trans also leaves much to be desired flow wise. Always thought they could've cast a rear cylinder head that had the exhaust port on the left side of the bike or even straight out the back of the head. Then the header could be routed directly over the transmission and (well heat shrouded), and out the left side of the bike behind the passenger foot rest.
Outstanding HDF Member
Joined: Feb 2007
Posts: 2,710
Likes: 6
From: Spokane, WA.
Hmmm
Road Captain
Joined: Nov 2007
Posts: 504
Likes: 2
From: NE IOWA
I put Vance and Hines true duals on my 2012 Ultra this winter. The pipes follow the same path as the stock pipes, except that they do not merge where the catalytic converter used to be. I liked it because it really did not change the look of the bike. Only the performance and sound.
I have the same set up and yes, they do appear to decrease in size, however it doesn't appear to be as much as the stockers. The pipe flattens out under the trans, but it looks like the overall diameter is close to the same. More like fettucini then linguini if that helps at all. lol
Dyno chart is right. The infamous everybody and they once said the world was flat too! We're here to tell you that the world is round and our true duals will out-perform any pipe out there. We just took off a 2-into-1 thunder header from a customer's bike and installed a set of our true duals. The dyno sheet was staggering! I'll post the video and print out this week.
Road Warrior
Joined: Oct 2010
Posts: 1,332
Likes: 34
From: Michigan
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Good one! Should've seen it, that one went over my head! You never know these days..... We thought that myth was debunked years ago, but still hear it all the time! Funny how things get around that aren't true.
