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jmccrary

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Hello everyone!  I am redoing all the electrical on the bike and while hooking everything up, I noticed something, weird.  I do have the "computers" off the bike right now, but just doing some voltage testing to make sure everything is working and noticed the lead going from the relay to the starter is ground.  Everything I read says it should be positive.  The other terminal on the relay is connected directly to the battery.

Any guidance is appreciated.  

I got this image from another topic, but it is the relay post circled in red as going to the starter that I am describing.

http://www.k100-forum.com/viewimage.forum?u=https%3A%2F%2Fi.imgur.com%2FDqkE4.jpg

TIA!!


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RicK G

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It is ground through .25 ohms of the starter windings so that when you press the start button it is 12v  which is why the load shed relay drops out.


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jmccrary

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Rick,
Thank you for the quick reply!  

I am changing the full harness over to the m.unit Blue and slowly putting it all back together.


Small plug, if anyone is in the Orlando area and loves to do wiring on a bike, I have beer lol


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jmccrary

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Hello everyone!  so, I hooked up the computers and the the same post on the relay remains at 12 negative volts.  The other wires going in react as expected when pushing the starter button.  I am use to a positive and a negative to make a motor turn, but this baffles me.  Does anyone have something that shows what should happen when pressing the starter button?  Much appreciated!


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RicK G

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PM sent


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats."  from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

jmccrary

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I did post this also on motorbrick to try to get a more answers.  

Motorbrick link

One thing I did recall after posting the original here, the starter motor did fall off the bench when it was removed...besides almost barely missing my toes, it was about a 3-4 foot fall.


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RicK G

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If you have electricals other than what the factory put there I am not in this count me out. Go talk to motogadget or whoever made it.


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats."  from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

robmack

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How can you measure -12V relative to ground on that post on the starter relay? That would mean you have +ve and -ve of the battery reversed? Are you using a standard, recommended battery? Have you hooked it up correctly? Could you be making a measurement error (i.e. switched voltmeter leads accidentally)?


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jmccrary

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@robmack wrote:How can you measure -12V relative to ground on that post on the starter relay?  That would mean you have +ve and -ve of the battery reversed?  Are you using a standard, recommended battery?  Have you hooked it up correctly?  Could you be making a measurement error (i.e. switched voltmeter leads accidentally)?
Rob,
When testing from the battery negative post on the battery to the post on the starter i get 0v.  When going from the positive post on the battery to the post on the starter, I get 13.5v.  The post on the starter is acting as a ground.  This is with the relay disconnected.  

I think the starter is shorted out causing the post to be a ground.

Can someone please confirm the following:
     Bike turned off
          1.  Multi-meter from negative battery post or frame to the post on the starter
          2.  Multi-meter from positive battery post to the post on the starter

My best guess is this:
     1.  you will get 0v.
     2.  you will get 0v.  I get 13.5v indicating a ground through the post.



Last edited by jmccrary on Fri Oct 05, 2018 3:59 pm; edited 1 time in total


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jmccrary

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@RicK G wrote:If you have electricals other than what the factory put there I am not in this count me out. Go talk to motogadget or whoever made it.
Rick, 
I appreciate the assistance!!

Justin


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Crazy Frog

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Please study this schematic and you will understand why the starter relay is grounded. Very Happy
When the starter is not running, it provides ground connection to the electrical.


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jmccrary

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Well, I sent CF a pm and got it right, so I can understand the interesting ways that was thought of to solve issues back before we had computers do it all for us.

On motobrick, I got an answer there too and seems that I will simply remove the starter from the bike.  Clamp it to a vice and see if it turns over.  Lucky for me, i have a very old machinist vice, so it should hold very well.  

Thanks again for everyone's help!!


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duck

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You don't need to remove it from the bike. Just jump 12V from the positive battery terminal to the terminal on the starter motor.


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jmccrary

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@duck wrote:You don't need to remove it from the bike. Just jump 12V from the positive battery terminal to the terminal on the starter motor.
I was debating on that first and if nothing happens then take it out.


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robmack

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As I mentioned over on Motobrick, I'd recommend pulling the motor and testing on the bench. It would be safer setup for testing and it would make the motor available for disassembly if required. You can test in-situ by shorting the terminals on the starter relay. That will serve to supply power to the starter motor. It's somewhat cramped in the area around the starter motor so jumping to the positive terminal of the battery is slightly more difficult and requires a bit more care.


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jmccrary

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@robmack wrote:As I mentioned over on Motobrick, I'd recommend pulling the motor and testing on the bench.  It would be safer setup for testing and it would make the motor available for disassembly if required.  You can test in-situ by shorting the terminals on the starter relay.  That will serve to supply power to the starter motor.  It's somewhat cramped in the area around the starter motor so jumping to the positive terminal of the battery is slightly more difficult and requires a bit more care.
Rob,
It’s very open for me right now.  However, you do make a great point if I need to take it apart and...it really is only two bolts to take it out. I tend to do things the hardway and realize later I should have listened, so this time it’s time to do things differently! Taking it out lol


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jmccrary

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And...it works!!!! 

Thank you again to everyone!!


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jmccrary

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@robmack wrote:As I mentioned over on Motobrick, I'd recommend pulling the motor and testing on the bench.  It would be safer setup for testing and it would make the motor available for disassembly if required.  You can test in-situ by shorting the terminals on the starter relay.  That will serve to supply power to the starter motor.  It's somewhat cramped in the area around the starter motor so jumping to the positive terminal of the battery is slightly more difficult and requires a bit more care.
Rob,
I seen your post on motobrick, but Johnny is blocked me from posting.  I will look more at the links

He said this(I am going to send him the middle finger when I get unblocked)

Sorry jmccrary, you are banned from posting and sending personal messages on this forum.
You were asked to post photos. You were warned defiance is futile. You chose defiance.
This ban is set to expire October 08, 2018, 10:43:48 PM.


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chris846

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The replies are all completely correct (what do you expect on this forum!) but if you're not yet grasping it, try this - the positive terminal on a starter motor is not like the positive terminal on a battery. The positive terminal on a starter motor is where you put the volts when you want it to run. 
Does that help?


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