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1981 400 special 2 carb o ring

Discussion in 'The Garage' started by Jasonsblue81, Jul 3, 2023.

  1. Jasonsblue81

    Jasonsblue81 colorado Kid

    Hey guys. finally took my carbs off my 81 special. Been driving it for three years without it idling. looks like all i need is that o ring that goes around the float needle housing. that housing is kinda loose going in and out . I see mikes xs part #48-1445 for a total replacement, but i would rather just replace the o ring. Does any body just sell a generic carb kit with that o ring?? probrably need 2. havent taken other carb apart yet. i have new intake boots also that i got from mikes xs.
     
  2. Jasonsblue81

    Jasonsblue81 colorado Kid

    the float bowl gaskets look fine. Maybe amazon has a o ring kit. oh yea, whats up with the black plug over the idle jet. . do i need to leave that on??
     
  3. CaptChrome

    CaptChrome XS400 Addict Top Contributor

    I think you are talking about the needle valve seat o-ring. It is part number 8F2-14147-00-00 and you can buy just one from Yamaha, but the
    MikesXS basic kit #48-1408 is a better deal, and as long as you have them open, you should just replace sealing parts in the float bowl.

    Yup, that needs to be installed (if you like the carbs to operate correctly).
     
  4. Jasonsblue81

    Jasonsblue81 colorado Kid

    ok i didnt see that 48-1408 because it was listed for xs650 ... but it said good for 82 xs400. mine is 81. same carbs i guess??
     
  5. Jasonsblue81

    Jasonsblue81 colorado Kid

    It looks like there is a little port hole that goes from the main jet to the idle jet . is that how the idle jet gets feul??? with the plug on??
     
  6. Jasonsblue81

    Jasonsblue81 colorado Kid

    noticed also no model numbers on the carbs ??
     
  7. CaptChrome

    CaptChrome XS400 Addict Top Contributor

    Yes, this will work on an '81. I have a 1981 Special II and I used this very kit on both carbs.

    Yes, there are internal drilled passages to allow the pilot jet work. The plug just covers the access port that allows you to get a screwdriver in there to remove it.

    The model number for the 1980 to 1982 SOHC bikes is Mikuni BS34 mark III
     
  8. Jasonsblue81

    Jasonsblue81 colorado Kid

    thanks captain chrome!!
     
  9. gpounce32768

    gpounce32768 XS400 Enthusiast

    Worth it to get new gaskets for the carb bowls while you're in there.

    If your carbs have the little tube which fits in a recess down in the side of the carb bowl, make sure the passage down to the bottom of the bowl is clear- that is part of the starting circuit.
     
  10. Jasonsblue81

    Jasonsblue81 colorado Kid

    clean carbs ,new air filters, bike runs great!! took long trip today. love my xs400
     

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