Honda Shadow Spirit 1100 Exhaust Modification

  • February 18, 2010 8:27 AM PST
    I have a set of Cobra drag pipes I want to install on my 2007 Shadow Spirit 1100 and need to know what I will need and how to do this.  I will rejet at a later date when it gets warmer weather.
    • 0 posts
    February 18, 2010 9:13 AM PST
    Easy to do with basic metric tools. You can figure on about an hour to do total.
    One thing I learned is that if you put a light layer of grease on the pipe where it attaches to the heads, it helps to seal better.
    If they are new pipes, they should have the basic instructions with them.
  • February 18, 2010 10:34 AM PST
    make sure you put in new crush gaskets.
  • February 25, 2010 6:57 AM PST
    Dudeman here, I was told by the dealer that backpressure needs to be maintained to prevent valves from burning.

    I was going to do a similer thing to my 96Shadow 1100 and wound up using the exhaust system from an Areo. Not the sound I was looking for but worked out in the long run.
    • 5420 posts
    February 25, 2010 7:04 AM PST
    One thing I learned the hard way is if there is rust on the bolts where the exhaust mounts to the head, and the mounting nuts are stuck on, don't force them. Be patient...Get some Liquid Wrench and soak them several times until you can get them loose with reasonable force. Do not add a 2 foot extension to the wrench handle and try to break them loose. Getting that broken bolt out of the head is a nightmare!!!!
  • February 25, 2010 7:13 AM PST
    Lucky wrote...
    One thing I learned the hard way is if there is rust on the bolts where the exhaust mounts to the head, and the mounting nuts are stuck on, don't force them. Be patient...Get some Liquid Wrench and soak them several times until you can get them loose with reasonable force. Do not add a 2 foot extension to the wrench handle and try to break them loose. Getting that broken bolt out of the head is a nightmare!!!!

    The longer the soak or "pretreat"  the better the chance things will go well...  I have applied penetration oil several days ahead of planed work day and reaplied each day..  turned as if near new when work day came.. 
  • February 25, 2010 9:42 AM PST
    Lucky wrote...
    One thing I learned the hard way is if there is rust on the bolts where the exhaust mounts to the head, and the mounting nuts are stuck on, don't force them. Be patient...Get some Liquid Wrench and soak them several times until you can get them loose with reasonable force. Do not add a 2 foot extension to the wrench handle and try to break them loose. Getting that broken bolt out of the head is a nightmare!!!!




    Mistake I will never make again lol. PB Blast works well too.

    • 1509 posts
    February 25, 2010 9:54 AM PST
    Spray the insid of the pipes with a flame proof black paint and be extreamly critical that pipe to head seal is absolutly sealed any air leak will blue pipes instantly, running rich will be good to breakin pipes gets carbon built up on inside of pipes to keep chrome silver when summer comes you will need to rejet carb or throw fames out the back.
    • 2072 posts
    February 25, 2010 9:58 AM PST
    throw flames out the back..................................................................


    Now that sounds friggin' COOL !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!   
    • Moderator
    • 19067 posts
    February 25, 2010 9:59 AM PST
    hgsc90 wrote...
    Lucky wrote...
    One thing I learned the hard way is if there is rust on the bolts where the exhaust mounts to the head, and the mounting nuts are stuck on, don't force them. Be patient...Get some Liquid Wrench and soak them several times until you can get them loose with reasonable force. Do not add a 2 foot extension to the wrench handle and try to break them loose. Getting that broken bolt out of the head is a nightmare!!!!

    The longer the soak or "pretreat"  the better the chance things will go well...  I have applied penetration oil several days ahead of planed work day and reaplied each day..  turned as if near new when work day came.. 

    Yeah pre-treat, pre-treat, pre-treat...

    Also, on the subject of jetting and backpressure. Since you said rejet I assume it is carb'd. I  would not wait to re-jet. In reality bu just putting drag pipes on a stock engine without other mods you will loose power!, Yes lose power. Therefore you will have performance problems. Without back pressure you will probably find some flat spots in the throttle. I am not familiar with the pipes you are using. I hope they have some sort of baffle. True open straight pipes require carb work or at minimum rejetting. Here is a link explaining in more detail what I just said...http://www.nightrider.com/biketech/exhaust.htm ; They talk Harley but the same rules apply to your bike.


  • February 25, 2010 10:13 AM PST
    I tried a set of open shot guns on my 99. Sounded good, if not a tad loud. BUT...I lost most of my low end grunt. I removed those pipes shortly after trying them out. I prefer the usable low end torque the bike offers.

    There is usually some give and take with these kinds of mods.

    jb
  • February 27, 2010 10:20 PM PST
    If you really love your bike and got the money to dyno it first with stock pipes then you have something to work with. After changing the pipes put a few miles on it and dyno it again, no guess work. You now have a before and after chart on paper to see what the fuel burn, torque and power is doing.

    The bike might be running rich enough now to accept new pipes, all models are different. If you can't afford to dyno it check the plug color before you change and a couple hundred miles after, if they turn ghost white you know it needs fattening up some and can guess at the jet size's to experiment with and results they will make.