1. Some members were not receiving emails sent from XJbikes.com. For example: "Forgot your password?" function to reset your password would not send email to some members. I believe this has been resolved now. Please use "Contact Us" form (see page footer link) if you still have email issues. SnoSheriff

    Hello Guest. You have limited privileges and you can't "SEARCH" the forums. Please "Log In" or "Sign Up" for additional functionality. Click HERE to proceed.

Do I need to jet straight pipes? 1987 xj 650

Discussion in 'XJ Modifications' started by Jordan Roark, Apr 9, 2016.

  1. Jordan Roark

    Jordan Roark New Member

    Messages:
    19
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    Jenison, Michigan
    My existing mufflers have holes and are old, im thinking about just removing and putting straight pipes on... any thoughts?
     
    Jordan Roark, Apr 9, 2016
    #1
  2. k-moe

    k-moe Pie, Bacon, Bourbon. Moderator Premium Member

    Messages:
    19,647
    Likes Received:
    6,755
    Trophy Points:
    113
    Location:
    The City of Seven Hills
    mid 90's Sportster mufflers.
     
    k-moe, Apr 9, 2016
    #2
    XJ550H likes this.
  3. Jordan Roark

    Jordan Roark New Member

    Messages:
    19
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    Jenison, Michigan
    Ok thanks
     
    Jordan Roark, Apr 11, 2016
    #3
  4. hogfiddles

    hogfiddles XJ-Wizard, Host-Central NY Carb Clinic Moderator Premium Member

    Messages:
    14,911
    Likes Received:
    5,222
    Trophy Points:
    113
    Location:
    near utica, new york
    1987?
     
    hogfiddles, Apr 17, 2016
    #4
  5. Indtune

    Indtune Member

    Messages:
    35
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Kennewick, WA
    Would aftermarket Sportster mufflers work with an xj550 without rejetting? Or do the Sportster mufflers need to be stock? I found some on ebay, slip-on, come with baffles.
     
    Indtune, Sep 7, 2016
    #5
  6. Toomanybikes

    Toomanybikes Well-Known Member

    Messages:
    2,836
    Likes Received:
    815
    Trophy Points:
    113
    Location:
    Tsawwassen bc
    No way to know until there installed.
    Oem ones would be pretty close,anything else ???
    I have aftermarket pipes on my MaximX750 and are fairly quiet and no re jetting was needed. Just idle mixture
     
    Toomanybikes, Sep 7, 2016
    #6
  7. sybe

    sybe Active Member

    Messages:
    576
    Likes Received:
    138
    Trophy Points:
    43
    Location:
    NYC - Brooklyn
    Exhaust with no back pressure = increased jetting.

    Also you can pretty much use any muffler if you know how to weld. I put on 3 inch Harley davidson mufflers i found on ebay. Cost me 50 + shipping. Went to a muffler shop to make the necessary connectors to clear the rear brake pedal and welded it on.

    I ran it with and without baffles. Without sounded great but for my neighbors i put them back on with minimal packing. I also preplanned this and jetted to compensate for the reduction of back pressure.
     
    sybe, Sep 7, 2016
    #7
  8. mlew

    mlew Well-Known Member

    Messages:
    3,090
    Likes Received:
    241
    Trophy Points:
    63
    Location:
    Apex, NC
    mlew, Sep 7, 2016
    #8
  9. hogfiddles

    hogfiddles XJ-Wizard, Host-Central NY Carb Clinic Moderator Premium Member

    Messages:
    14,911
    Likes Received:
    5,222
    Trophy Points:
    113
    Location:
    near utica, new york
    The Xj mufflers are already about as free-blowing as you can get. There's minimal back-pressure. The free-flowing shouldn't be an issue. The bigger issue comes when you start playing with air/fuel mixtures.......as in: pods vs. airbox, stock air filter vs. k&n filter, etc.....
     
    hogfiddles, Sep 7, 2016
    #9
    k-moe and Indtune like this.
  10. Indtune

    Indtune Member

    Messages:
    35
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Kennewick, WA
    Sweet! Thanks guys! I had my xj550 sitting for 3 years, almost sold it. Got a wild hair and decided to get it going. I'll be posting on other threads regarding other questions and concerns. Learned a lot from the forums here, lots of help!
     
    Indtune, Sep 7, 2016
    #10
  11. Indtune

    Indtune Member

    Messages:
    35
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Kennewick, WA
    Also... Does anyone know the diameter of the Muffler opening right after the collector? As in, where you'd cut off the muffler? Or is it bolt on? I haven't measured it yet, looking at pipes.
     
    Indtune, Sep 7, 2016
    #11
  12. sybe

    sybe Active Member

    Messages:
    576
    Likes Received:
    138
    Trophy Points:
    43
    Location:
    NYC - Brooklyn
    If he ditches the H pipe and goes with straight pipes he would definitely lose back pressure.
     
    sybe, Sep 7, 2016
    #12
  13. hogfiddles

    hogfiddles XJ-Wizard, Host-Central NY Carb Clinic Moderator Premium Member

    Messages:
    14,911
    Likes Received:
    5,222
    Trophy Points:
    113
    Location:
    near utica, new york
    I don't know as he would lose much back pressure… He would lose the L/R equalization-
     
    hogfiddles, Sep 7, 2016
    #13
  14. Indtune

    Indtune Member

    Messages:
    35
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Kennewick, WA
    Not looking into straight pipes, I know the bends are important. Just a different look and sound without having to rejet and with minimal simple adjustments. I'm pretty new to working on my own bike, just learning as I go.
     
    Indtune, Sep 7, 2016
    #14
  15. k-moe

    k-moe Pie, Bacon, Bourbon. Moderator Premium Member

    Messages:
    19,647
    Likes Received:
    6,755
    Trophy Points:
    113
    Location:
    The City of Seven Hills
    And the scavenging the engine gets from the pulsing through the crossover.
     
    k-moe, Sep 7, 2016
    #15
    hogfiddles likes this.
  16. Indtune

    Indtune Member

    Messages:
    35
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Kennewick, WA
    Ok. What's a crossover? I'm guessing it's in the stock muffler, as I think I've read that in a thread. Sorry, newbie here. Is there an aftermarket muffler out there that compensates for that, or easy tuning needed? I'm ok with sticking to stock mufflers if it means saving the lifespan of the ol' girl...
     
    Indtune, Sep 7, 2016
    #16
  17. Polock

    Polock Well-Known Member

    Messages:
    9,751
    Likes Received:
    2,097
    Trophy Points:
    113
    Location:
    Beaver Falls, PA
    Polock, Sep 7, 2016
    #17
    Indtune likes this.
  18. mc1oo1

    mc1oo1 Member

    Messages:
    94
    Likes Received:
    26
    Trophy Points:
    18
    Location:
    LB,Ca
    Get yourself some stock Sportster pipes. They're the perfect ID in most cases and will have a split that you can use a new clamp on. Plus they give off a nice purr which works with the zing of the inline-4.
     
    mc1oo1, Sep 7, 2016
    #18
    Indtune likes this.

Share This Page