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.

Question About Float Bowl Needle Valve

Discussion in 'XJ Technical Chat' started by moshumi13, Feb 13, 2012.

  1. moshumi13

    moshumi13 Member

    Messages:
    85
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Salisbury, MD (near Ocean City!)
    How important is it that the spring inside the needle valve still function? Can I still set my floats without the spring working. The spring is inside the needle valve and allows the tiny button that contacts with the float to depress about 1 cm. If it's not uber important I'd like to go ahead and reuse them. This is concerning a Mikuni BS32 carb from a '85 FJ600. Should be very similar to BS28 model.

    Thanks

    Nevermind. I just set the floats to my known good needle valve and then installed the floats with the stuck spring needle valves and they measured the same. I think the spring adds extra closure pressure. Will find out when I put the carbs on the bike. Still waiting on key and battery, though.
     
    moshumi13, Feb 13, 2012
    #1
  2. tskaz

    tskaz Active Member

    Messages:
    1,878
    Likes Received:
    17
    Trophy Points:
    38
    Location:
    Saint Louis, Michigan
    It would not be good to reuse a needle that doesn't function correctly.

    The float rises to presss that spring in and without the tension of the spring the valve will never seal properly.
     
    tskaz, Feb 13, 2012
    #2
  3. moshumi13

    moshumi13 Member

    Messages:
    85
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Salisbury, MD (near Ocean City!)
    That sucks. Guess I'll have to get some new ones. At least the float height is already set.

    Thanks
     
    moshumi13, Feb 13, 2012
    #3
  4. bigfitz52

    bigfitz52 Well-Known Member Premium Member

    Messages:
    21,283
    Likes Received:
    419
    Trophy Points:
    83
    Location:
    Rural SE Michigan 60 miles N of Motown
    Be sure to double check it after replacing the needle valves; it doesn't take much variation to throw the float levels way off.
     
    bigfitz52, Feb 13, 2012
    #4
  5. tskaz

    tskaz Active Member

    Messages:
    1,878
    Likes Received:
    17
    Trophy Points:
    38
    Location:
    Saint Louis, Michigan
    +1

    New needle valves are usually about 1mm longer and that's about all the variation Yamaha allowed for most carbs.
     
    tskaz, Feb 13, 2012
    #5

Share This Page