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Thread: Strange electrical gremlins

  1. #1
    apriliaforum Member
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    Strange electrical gremlins

    Hey guys...hope someone can point me in the right direction.
    When I hit the starter button I lose total elec power. Then it comes back many minutes later???? Push starter, it's gone again!!!
    I noticed +12V on the frame during one of these episodes, which tells me...no ground. So here's what I need to know ...
    1) Where are the main ground points???
    2) Why would the power return with such regularity???
    Thanks in advance...
    JohnB

  2. #2
    apriliaforum expert deefred's Avatar
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    For the main ground "Battery - Engine" just follow the ground lead from the battery to where it connects on the left side of the engine. Its a bit hidden.

    There is also another ground point on the right side of the engine just opposite of the left one.
    Two or three wires (don´t remember how many now) are connected to the right hand side ground. You will need to move the radiator expansion bottle slightly to access it.
    This one is also well hidden.
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  3. #3
    apriliaforum Member
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    Hi John, have you tried shorting the contacts of the starter relay, screwdriver or similar.

  4. #4
    apriliaforum expert RobC's Avatar
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    or try shorting the engine cases to the battery -ve with a jump lead - that would prove whether or not it's a bad earth.

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    Hey fellas...thanks for the speedy replies.
    I did try jumping the terminals on the starter solenoid...no good.
    My main problem right now is that the bike runs fine!!! That's my luck! Now that I'm ready to tackle it, the problem has disappeared. Thats why I want to find all the grounds and check them out. The only silver lining right now is that nobody is riding in NY right now. Too much snow!
    BTW what does the starter relay do? the little square one. Could this be my problem???

    Thanks again...keep them ideas coming
    JohnB

  6. #6
    apriliaforum expert Motech's Avatar
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    Your 12 volts to frame... I assume that's volt-drop between battery negative and frame? And I assume it's closer to zero when symptom is gone?

    Crank starter when measuring volt-drop between battery negative and engine block. If your reading is above a volt cranking, you've got resistance somewhere that might intermittently go "open". Back probe up the ground wire from the engine to the battery. When your crankjing volt-drop reads under a volt, you've passed your resistance, go back and fix it.

    Same goes for every ground.

    I suspect it's probably at one end or the other, and a good terminal service/tightening will fix it.

    You can test positive side same way, with cranking volt-drop measurements between battery positive and the powered connection at whichever component/fuse/connector you are testing.
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  7. #7
    apriliaforum expert Shippers's Avatar
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    Quote Originally Posted by deefred View Post
    For the main ground "Battery - Engine" just follow the ground lead from the battery to where it connects on the left side of the engine. Its a bit hidden.

    There is also another ground point on the right side of the engine just opposite of the left one.
    Two or three wires (don´t remember how many now) are connected to the right hand side ground. You will need to move the radiator expansion bottle slightly to access it.
    This one is also well hidden.
    There is one ground wire on the left of the bike and two on the right, these two are together on the same screw. As Deefred said they are well hidden.You will need a long allen key to get to them. If they are not clean this can cause issues, been there done that. HTH
    Mark


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    Gentlemen! Excellent answers, I'm much obliged. So I'll hunt down both of these grounds and perform a dynamic voltage drop test. Hopefully this will reveal my problem.
    First though I have to shovel my way through many layers of snow and ice to get to the shed brrr...winter suxs!!!
    Thanks again
    JohnB

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