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.

What does the over revolution switch do???

Discussion in 'XJ Technical Chat' started by jdrockin, Feb 28, 2009.

  1. jdrockin

    jdrockin Member

    Messages:
    81
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    WI
    Hi all.
    I have an XJ900 and I bought a new speedo/tach for it. I'm going over the wiring and I have no idea what the over revolution switch does. Can anyone help me out? Do I even need to worry about it? Also, if anyone has any tips on hooking up the Acewell speedo let me know. Or looses ends that aren't addressed in the instructions, things I should know about etc... Thanks, Joel
     
    jdrockin, Feb 28, 2009
    #1
  2. gurgietrueshot

    gurgietrueshot Member

    Messages:
    190
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Kansas
    I don't know about the revolution switch that but the Acewell is pretty straight forward. I found that plugging straight into the ignition coil was much better than wrapping the wire around spark plug wire for the tach. I also added the 1MOh resistor inline with the tach wire. Make the reading less jumpy.

    Here is my write up on putting one on my 650 Seca. I'll be adding a few more pics tonight.

    http://xjbikes.com/Forums/viewtopic/t=15565.html
     
    gurgietrueshot, Feb 28, 2009
    #2
  3. MN-Maxims

    MN-Maxims St. Paul Minnesota

    Messages:
    3,067
    Likes Received:
    114
    Trophy Points:
    63
    Location:
    Saint Paul, MN
    Sounds like a rev limiter to me.
     
    MN-Maxims, Feb 28, 2009
    #3
  4. sushi_biker

    sushi_biker Member

    Messages:
    576
    Likes Received:
    0
    Trophy Points:
    16
    Location:
    Maryland
    Just off the top of my head, the over-rev switch sounds like a safety limiter to me. I'm guessing that the over-rev switch takes a signal from the tacho so that it knows when to cut out and kill the engine.
     
    sushi_biker, Feb 28, 2009
    #4
  5. Kiwi

    Kiwi Member

    Messages:
    77
    Likes Received:
    0
    Trophy Points:
    6
    Location:
    New Zealand
    I'm not sure of the actual specifics of the XJ but on other Yamaha models what it does to rev limit is drop a coil, this would have the effect of killing 2 cylinders, revs drop, below rev limit coil fires again...

    I'd assume that is what happens here.
     
    Kiwi, Mar 1, 2009
    #5

Share This Page