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.

XJ900F, Generator upgrade

Discussion in 'XJ Technical Chat' started by Arnaud, Oct 4, 2025.

  1. Arnaud

    Arnaud Member

    Messages:
    71
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Netherlands
    Despite idling at 1100 rpm or slighly above, the onboard Voltmeter shows the battery Voltage dropping below 11,5V when waiting a little longer at a traffic light with lights on.

    The Motobatt is measured and found healthy.

    Is there an upgrade for the generator available, of are there people who had their stator rewinded with more windings?
     
    Arnaud, Oct 4, 2025
    #1
  2. Franz

    Franz Well-Known Member

    Messages:
    4,369
    Likes Received:
    1,234
    Trophy Points:
    113
    Location:
    Scotland UK.
    The alternator does not charge the battery below 2000rpm. Rev the engine and check the battery voltage.
     
    Franz, Oct 4, 2025
    #2
  3. Arnaud

    Arnaud Member

    Messages:
    71
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Netherlands
    ? Normally it starts charging at 1100 rpm? (Manual states that's why idling at 1100 rpm.
    Charging is okay at 14,4V lights off..
     
    Arnaud, Oct 4, 2025
    #3
  4. Franz

    Franz Well-Known Member

    Messages:
    4,369
    Likes Received:
    1,234
    Trophy Points:
    113
    Location:
    Scotland UK.
    I read the 2000 rpm figure here. Must be incorrect.
     
    Franz, Oct 4, 2025
    #4
  5. Arnaud

    Arnaud Member

    Messages:
    71
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    Netherlands
    Strange.. when i carefully open the throttle-normally- Voltage increases from 1100 rpm upwards..
     
    Arnaud, Oct 4, 2025
    #5
  6. Franz

    Franz Well-Known Member

    Messages:
    4,369
    Likes Received:
    1,234
    Trophy Points:
    113
    Location:
    Scotland UK.
    Franz, Oct 4, 2025
    #6
  7. Franz

    Franz Well-Known Member

    Messages:
    4,369
    Likes Received:
    1,234
    Trophy Points:
    113
    Location:
    Scotland UK.
    Voltage gradually increases. Makes sense.
     
    Franz, Oct 4, 2025
    #7

Share This Page