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Help needed with new exhaust on m8

  • Khrusty666
    Khrusty666
    4 years ago
    I'm at my wits end.
    I have a set of freedom pipes I'm trying to install on my 18 fatboy 114.
    After working my way around incorrect brackets (don't get me started there). 
    I got to put on my new pipes, but they just won't fit in the exhaust manifold. 
    Not even enough to show enough thread to put nut on. 
    I have measured with verniers, the stock HD pipe at 46.3mm at its widest, and the freedom pipes are 48.6mm
    Also the harley pipes start off tapered then to the larger, but the freedoms are not tapered at all. 

    If I were to take out the manifold gaskets, they would fit perfectly. Surely they can't be made to not use a gasket? 

    There were no instructions with the pipes, and nothing on their website. 

    My bike is in pieces, please anyone with some advice is greatly appreciated. 
  • wello
    wello
    4 years ago
    Quoting Khrusty666 on 09 May 2020 07:42 AM

    I'm at my wits end.

    I have a set of freedom pipes I'm trying to install on my 18 fatboy 114.
    After working my way around incorrect brackets (don't get me started there). 
    I got to put on my new pipes, but they just won't fit in the exhaust manifold. 
    Not even enough to show enough thread to put nut on. 
    I have measured with verniers, the stock HD pipe at 46.3mm at its widest, and the freedom pipes are 48.6mm
    Also the harley pipes start off tapered then to the larger, but the freedoms are not tapered at all. 

    If I were to take out the manifold gaskets, they would fit perfectly. Surely they can't be made to not use a gasket? 

    There were no instructions with the pipes, and nothing on their website. 

    My bike is in pieces, please anyone with some advice is greatly appreciated. 

    is it this one ?
    https://www.youtube.com/watch?v=aXZIWmH6Ud0

  • Khrusty666
    Khrusty666
    4 years ago
    No, they are straight 2-2 (with a crossover).
    Kinda like the V&H big shot staggered. 


  • Khrusty666
    Khrusty666
    4 years ago


    IMG_20200509_180218.jpg
    IMG_20200509_180311.jpg
  • Khrusty666
    Khrusty666
    4 years ago
    You can see the difference between the two.
  • perthhog
    perthhog
    4 years ago
    Tapered gasket vs flat gasket  you will have to swap the gasket s  me thinks 
  • Khrusty666
    Khrusty666
    4 years ago
    Quoting perthhog on 09 May 2020 08:47 AMedited: 09 May 2020 08:49 AM

    Tapered gasket vs flat gasket  you will have to swap the gasket s  me thinks 

    I think you have hit the nail on the head.
    I got replacement gaskets, and they are tapered. 

    I need to get the screamin eagle flat gaskets. 

    Just my luck, I'm a shift worker, and now can't get them until next week. 


    Thanks guys appreciate the help. 
  • Ratbob
    Ratbob
    4 years ago
    Quoting perthhog on 09 May 2020 08:47 AMedited: 09 May 2020 08:49 AM

    Tapered gasket vs flat gasket  you will have to swap the gasket s  me thinks 

    Quoting Khrusty666 on 09 May 2020 09:04 AM

    I think you have hit the nail on the head.

    I got replacement gaskets, and they are tapered. 

    I need to get the screamin eagle flat gaskets. 

    Just my luck, I'm a shift worker, and now can't get them until next week. 


    Thanks guys appreciate the help. 

    Yes the SE gaskets are the go but as they are quite thin (pic on left) fit two per side, they will compress nicely. 
    Occasionally one isn’t enough and it’s bloody annoying to do the job twice.


    7361F2E2-44CC-4B93-9C54-697A6FC4A871.jpeg
  • Khrusty666
    Khrusty666
    4 years ago
    Good point
    I might grab 2ea

    Was going to use some permaflex, but this makes sense. 
    Cheers
  • beaglebasher
    beaglebasher
    4 years ago
    That is good thinking Rat.
    Will keep that one in mind.
    How did you learn that?
  • Ratbob
    Ratbob
    4 years ago
    Quoting beaglebasher on 10 May 2020 04:24 AM

    That is good thinking Rat.

    Will keep that one in mind.
    How did you learn that?

    Hi Beagle, I asked the forum a similar question last year and I think it was John.R who mentioned that some folks double up for some reason. 
    Having already failed to fit my 2-1 pipes twice with the conical gasket, I moved to the SE and took John.Rs advice, worked perfectly, no need to redo a fourth time. Bloody good knowledge pool our forum. 
  • dicko
    dicko
    4 years ago
    Quoting beaglebasher on 10 May 2020 04:24 AM

    That is good thinking Rat.

    Will keep that one in mind.
    How did you learn that?

    Quoting Ratbob on 10 May 2020 05:08 AM

    Hi Beagle, I asked the forum a similar question last year and I think it was John.R who mentioned that some folks double up for some reason. 

    Having already failed to fit my 2-1 pipes twice with the conical gasket, I moved to the SE and took John.Rs advice, worked perfectly, no need to redo a fourth time. Bloody good knowledge pool our forum. 

    You know what , I think the original exhaust looks fuckin great, just remove the cat, it will perform perfectly.
    Think this , the pressure pulse from exhaust flows through the pipe from each cylinder, ,( at piston/rpm speed)
     
     It then meets the crossover / balance pipe, where it can then release through two pipes/mufflers effectively doubling the available output for that pulse.
    My experience tuning these things has proved to me the balanced /crossover pipe is always the best for all round performance.
  • Ratbob
    Ratbob
    4 years ago
    Quoting beaglebasher on 10 May 2020 04:24 AM

    That is good thinking Rat.

    Will keep that one in mind.
    How did you learn that?

    Quoting Ratbob on 10 May 2020 05:08 AM

    Hi Beagle, I asked the forum a similar question last year and I think it was John.R who mentioned that some folks double up for some reason. 

    Having already failed to fit my 2-1 pipes twice with the conical gasket, I moved to the SE and took John.Rs advice, worked perfectly, no need to redo a fourth time. Bloody good knowledge pool our forum. 

    Quoting dicko on 10 May 2020 09:16 AM

    You know what , I think the original exhaust looks fuckin great, just remove the cat, it will perform perfectly.

    Think this , the pressure pulse from exhaust flows through the pipe from each cylinder, ,( at piston/rpm speed)
     
     It then meets the crossover / balance pipe, where it can then release through two pipes/mufflers effectively doubling the available output for that pulse.
    My experience tuning these things has proved to me the balanced /crossover pipe is always the best for all round performance.

    Eh? Balance pipes need to join at specific locations along each pipe in tune with the pulse within each pipe. Removing the CAT simply creates an untuned chamber in which the exhaust gas slows down negating any scavenging or pulse balancing effect. The gas then has to speed up as it gets forced through the muffler/s hardly ideal.
  • Khrusty666
    Khrusty666
    4 years ago
    The cats are in the stock slips on.
    I had eliminator slip ons before I bought these pipes which have a crossover pipe in the baffle section, of which I'm sure had R&D testing done for that model. 

    I have a V&H FP3 which I use to tune the bike. 

    I didn't want to sacrifice low end torque, hence the 2 pipe crossover. 
  • Ratbob
    Ratbob
    4 years ago
    Quoting Ratbob on 10 May 2020 05:08 AM

    Hi Beagle, I asked the forum a similar question last year and I think it was John.R who mentioned that some folks double up for some reason. 

    Having already failed to fit my 2-1 pipes twice with the conical gasket, I moved to the SE and took John.Rs advice, worked perfectly, no need to redo a fourth time. Bloody good knowledge pool our forum. 

    Quoting dicko on 10 May 2020 09:16 AM

    You know what , I think the original exhaust looks fuckin great, just remove the cat, it will perform perfectly.

    Think this , the pressure pulse from exhaust flows through the pipe from each cylinder, ,( at piston/rpm speed)
     
     It then meets the crossover / balance pipe, where it can then release through two pipes/mufflers effectively doubling the available output for that pulse.
    My experience tuning these things has proved to me the balanced /crossover pipe is always the best for all round performance.

    Quoting Ratbob on 10 May 2020 09:49 AM

    Eh? Balance pipes need to join at specific locations along each pipe in tune with the pulse within each pipe. Removing the CAT simply creates an untuned chamber in which the exhaust gas slows down negating any scavenging or pulse balancing effect. The gas then has to speed up as it gets forced through the muffler/s hardly ideal.

    Damn, ignore that thanks Khrusty and Dicko, got my posts mixed up with a Sport Glide. Another senile seniors moment.
  • Khrusty666
    Khrusty666
    4 years ago


    IMG_20200511_150327.jpg
    IMG_20200511_152030.jpg
  • Khrusty666
    Khrusty666
    4 years ago
    Thanks for everyone's help.
    Pipes are now on, base tune flashed, and ready for a test ride. 

    Used the 2 gaskets per cylinder, and it worked a treat. 
    Love the lines of the pipes, and a nice deep rumbling note. 
    Exactly what I was looking for. 
  • Ratbob
    Ratbob
    4 years ago
    Yeah she looks great Khrusty, like the end tips. 
  • Khrusty666
    Khrusty666
    4 years ago
    Cheers mate
    The funny thing is, I thought I ordered the chrome tips, but now they are on the bike, I dig the black
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