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Discussion Starter #1
I just got my battery today and now the trouble shooting begins.

This bike had been neglected for years so there is no telling what could be wrong.

It’s a 2000 750 Monster and when I removed the wire harness I labeled everything. There were two wires that weren’t connected to anything so they never got labeled, and I’m still wondering where they go.

One is a connector, and the other is a wire that I would have bet was a ground by the look of it. Come to find out when I put my probe on it, that bastard is hot. I guess you can never assume.

It’s a very thick wire with a ground style connector on the end so I have to assume that it carries a very heavy load, my guess is that it’s the hot to the starter, but when I assume...

These two wires are right off of the main harness and I’m wondering if anyone can help.

I have a service manual, but electrical isn’t my thing. I can manage when things are connected correctly, but when wires are hanging loose, I’m lost.

This heavy wire is a constant hot so it may go to the solenoid but I don’t want to guess.

The first picture are the two wires and the second is the connector only. Not sure why my hands look purple, they’re not.

Any ideas?

...one more thing. There are two wires an the solenoid right now. One goes from the engine to the selinoid and the other comes out from the solenoid to I believe the positive on the battery if I remember correctly...



 

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Discussion Starter #2
I wish there was a wiring diagram for dummies that shows where all connectors go.
 

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That is half a connector. If you don’t have the other half on the bike maybe whatever plugged in there has been removed. Dis you check the color code for those wires on a wiring diagram ?
 

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the white one goes into the back of the starter solenoid. that's the only place they use that connector on the bike.

the other one is one of the battery / starter / earth main leads. maybe the earth? battery earth to the frame at the bolt that holds the battery box on the left? if you show us what the rest of it looks like it might be more obvious.
 

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The black one is a ground. Clean frame to bare metal and bolt it to the frame or engine, then run a wire from that bolt back to your battery ground on the frame.
 

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Discussion Starter #6
All very helpful thank you.

I ended up buying a Haynes Manual that should help me.
 

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Discussion Starter #7
the white one goes into the back of the starter solenoid. that's the only place they use that connector on the bike.

the other one is one of the battery / starter / earth main leads. maybe the earth? battery earth to the frame at the bolt that holds the battery box on the left? if you show us what the rest of it looks like it might be more obvious.
I didn’t see a place on the solenoid that would accept a plug, but I’ll look again. It makes sense.
 

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Discussion Starter #8
The black one is a ground. Clean frame to bare metal and bolt it to the frame or engine, then run a wire from that bolt back to your battery ground on the frame.
As you probably know, there aren’t a lot of bolts on this frame. I can attach it to the bolt that holds the battery box in place, or I can bolt it to the timing belt cover on the engine.

Are both acceptable?
 

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Discussion Starter #9
the white one goes into the back of the starter solenoid. that's the only place they use that connector on the bike.

the other one is one of the battery / starter / earth main leads. maybe the earth? battery earth to the frame at the bolt that holds the battery box on the left? if you show us what the rest of it looks like it might be more obvious.
Not sure if this is helpful. Put a penny there for scale.



 

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Discussion Starter #10
Could the black wire possibly be this wire that attaches to the underside of the negative battery cable? The problem with that is I don’t think it will reach.

angel locsin age
 

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It is a ground wire. You can ground to a clean bare metal spot on the engine or frame , wherever the wire will conveniently reach. Then if you run a jumper wire to the spot on the frame where the battery grounds you will have no “ ground related” problems. This is called Single Point Grounding. Many
people with older bikes with marginal electrical systems do this to guarantee a good ground.
 

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It is a ground wire. You can ground to a clean bare metal spot on the engine or frame , wherever the wire will conveniently reach. Then if you run a jumper wire to the spot on the frame where the battery grounds you will have no “ ground related” problems. This is called Single Point Grounding. Many
people with older bikes with marginal electrical systems do this to guarantee a good ground.
 

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Discussion Starter #13
Great advice. Thank you!!!

Question on the jumper wire. If you add the jumper where the ground is mounted to the frame, where does the other end attach to???
 

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Discussion Starter #14
Oh I think I get it. You add the jumper to where you ground the battery ground, right?

Is there any special place to ground the battery ground or just any bare spots on the frame?
 

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Discussion Starter #15
I know this isn’t very helpful, but the two wires in question are in yellow.

According to the vague reference, the plug goes to the solenoid. The other is the one in question.

Does this help any, or just compound the question?

cheapest gas station around me
 

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As Belter said, the Plug definitely goes to the solenoid. The other can only be Ground/Earth or the constant live wire that also goes to the Solenoid. A quick multimeter or bulb test should clear that up.
 

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Discussion Starter #17
To determine if it’s a ground or a live solenoid wire, when I test it with my power probe, do I test it with the key on or off? And if it’s a 12V live that means solenoid?
 

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Discussion Starter #18 (Edited)
I guess another question could be does anybody have three thick wires on their solenoid? I have one thick wire going to the starter solenoid I have the other thick wire going to the positive on the battery. I wonder if someone could look at their solenoid and see if there are three wires attached? right now mine has two.
 

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Solenoid has two thick wires. One comes from the battery to the solenoid, the other goes from the solenoid down lown on the motor to the starter.

To test if its live or not.
Key off.
Multimeter set to 20V.
Measure between the end of the Thick wire in question to any good earth or Battery Neg terminal. If its live and belongs on the Solenoid it will show Battery Voltage (12+V) if it shows 0 its an earth wire. If you dont have a Multimeter, buy one, or get a 12V bulb and two lengths of wire. Connect the bulb up as above. If it lights up its Live.
 

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Discussion Starter #20
I have a meter. I’ll test this tonight. Great advice and exactly what I needed.

Thank you. I’ll let you know what happened.
 
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