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Discussion Starter · #1 ·
I just got a 1982 GL500 for 600. Already half way built into the cafe that I envisioned. I’m fairly savvy in electrical and mechanical as I am a technician. The guy before me got the bike and never finished it. He did some kind of janky wiring work with the ignition system. I’m attempting to get it to crank. The starter turns if I bypass everything and just hook it up to power and ground, my ignition switch has power and ground. Battery is good, only thing I have left is the starter solenoid. I’m fairly certain that the solenoid is bad but would like some confirmation. If I hook up everything like it should be and instead of hooking up the power that goes to the starter to the solenoid, if I put it directly to the battery it will crank. Otherwise it won’t crank.
 

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follow the solenoid wires down to the plug under the battery and unplug it. Direct from the battery positive run a rire to the yellow/red wire and from the negative to the green/red.

The motor should crank. If not the solenoid {or battery} are fubar.

Do you have a multimeter?
 

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Discussion Starter · #3 ·
I just got a 1982 GL500 for 600. Already half way built into the cafe that I envisioned. I’m fairly savvy in electrical and mechanical as I am a technician. The guy before me got the bike and never finished it. He did some kind of janky wiring work with the ignition system. I’m attempting to get it to crank. The starter turns if I bypass everything and just hook it up to power and ground, my ignition switch has power and ground. Battery is good, only thing I have left is the starter solenoid. I’m fairly certain that the solenoid is bad but would like some confirmation. If I hook up everything like it should be and instead of hooking up the power that goes to the starter to the solenoid, if I put it directly to the battery it will crank. Otherwise it won’t crank.
208739

follow the solenoid wires down to the plug under the battery and unplug it. Direct from the battery positive run a rire to the yellow/red wire and from the negative to the green/red.

The motor should crank. If not the solenoid {or battery} are fubar.

Do you have a multimeter?
Yea I have a multimeter, unfortunately my bike is at work and I can only work on it at lunch and after work for a few hours. I will try this out tomorrow and get back to you.
 

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If you have access to a multimeter make sure the green /red makes a connection back to ground. If not, see if it will with the clutch pulled. It may be a neutral or clutch switch issue.

Also test for power arriving at the yellow/red wire when the start button is pushed.
 

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'84 CX650E that is evolving into a GL500
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Welcome to the forum. Please add your location and your bike's model and model year to your profile so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.

While you are in the Wiki get the colour wiring drawing for your model and the Honda Wire Color Codes chart to help you figure out the current problem.

This drawing may help too
208747


I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. Check the date codes on your tires and replace them if they are over 5 years old no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid). And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).

The best advice anyone can give you about customizing any vehicle is to get it safe & reliable in more or less original condition and use it for a while before you start making any changes so it can tell you what changes it needs to make it do what you want/need better. That approach almost always results in something you actually want to keep and use but making changes based on style or on what someone else (who may or may not really understand how the changes affect the way it works) has done often results in a piece of expensive yard art that you can't stand sitting on for more than a few minutes and might even be dangerous.
 

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Discussion Starter · #6 ·
follow the solenoid wires down to the plug under the battery and unplug it. Direct from the battery positive run a rire to the yellow/red wire and from the negative to the green/red.

The motor should crank. If not the solenoid {or battery} are fubar.

Do you have a multimeter?
Apologize for the late response. Wasn’t able to work on the bike the past couple days. Attemteped to run the wires from the plug to the battery and it didn’t crank.
 

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Discussion Starter · #7 ·
View attachment 208739

Yea I have a multimeter, unfortunately my bike is at work and I can only work on it at lunch and after work for a few hours. I will try this out tomorrow and get back to you.
Apologize for the late response. Wasn’t able to work on the bike the past couple days. Attemteped to run the wires from the plug to the battery and it didn’t crank.
If I leave the plug, plugged into the solenoid and I test the yellow/red to positive and the green/red to negative then it cranks. No turn over though
 

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1978 CX500 "The Grub", '83 GL650, '82 GL500 Project "AdventureWing", '79 CX500C, '78 CX500 Scrambler
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If I leave the plug, plugged into the solenoid and I test the yellow/red to positive and the green/red to negative then it cranks. No turn over though
Cranking is turning over, unless it can't make a full rotation. Turning over, but no fire?
 

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'84 CX650E that is evolving into a GL500
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The solenoid consists of a set of contacts attached to a magnet and a coil. When current passes through the coil a magnetic field forms that pulls the magnet and closes the contacts. This is done so that a low current (which doesn't require heavy wiring) can control a big current.

As you can see in the drawing above, adding those jumper wires connected the solenoid's coil directly across the battery so that the contacts closed and current could flow through them to the starter motor. This demonstrates that the solenoid is not the cause of your problem.

The next step is to leave the jumper connected to the battery negative off and see if it cranks when you connect the positive jumper (cranking and "turning over" are the same thing; Don't worry about getting it to fire yet - one problem at a time).
  • If it does the problem is somewhere between the battery + and the red/yellow wire, perhaps a disconnected or broken wire but more likely a dirty Start button.
  • If not the problem is between the green/red wire and ground so you need to look at the neutral switch and the clutch switch.

BTW: What kind of technician are you?
 

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Discussion Starter · #10 ·
The solenoid consists of a set of contacts attached to a magnet and a coil. When current passes through the coil a magnetic field forms that pulls the magnet and closes the contacts. This is done so that a low current (which doesn't require heavy wiring) can control a big current.

As you can see in the drawing above, adding those jumper wires connected the solenoid's coil directly across the battery so that the contacts closed and current could flow through them to the starter motor. This demonstrates that the solenoid is not the cause of your problem.

The next step is to leave the jumper connected to the battery negative off and see if it cranks when you connect the positive jumper (cranking and "turning over" are the same thing; Don't worry about getting it to fire yet - one problem at a time).
  • If it does the problem is somewhere between the battery + and the red/yellow wire, perhaps a disconnected or broken wire but more likely a dirty Start button.
  • If not the problem is between the green/red wire and ground so you need to look at the neutral switch and the clutch switch.

BTW: What kind of technician are you?
I was a technician at Nissan, now I wire off road vehicles at a private shop. I never really did wiring at Nissan other than just replacing/ repairing harness from rodent damage.
When I give the yellow/red wire power it cranks/turns over but no fire. I ordered a solenoid a couple days ago anyway just to have a new one. Could I be the start switch? When I press the start switch I don’t have any power coming from the yellow/red. Which I’m pretty sure I should.When I jump the wires on the solenoid (positive to the starter) it will crank.
 

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Discussion Starter · #11 ·
I was a technician at Nissan, now I wire off road vehicles at a private shop. I never really did wiring at Nissan other than just replacing/ repairing harness from rodent damage. I did little chasing wires on a diagram at Nissan
When I give the yellow/red wire power it cranks/turns over but no fire. I ordered a solenoid a couple days ago anyway just to have a new one. Could I be the start switch? When I press the start switch I don’t have any power coming from the yellow/red. Which I’m pretty sure I should.When I jump the wires on the solenoid (positive to the starter) it will crank.
 

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Discussion Starter · #13 ·
The solenoid consists of a set of contacts attached to a magnet and a coil. When current passes through the coil a magnetic field forms that pulls the magnet and closes the contacts. This is done so that a low current (which doesn't require heavy wiring) can control a big current.

As you can see in the drawing above, adding those jumper wires connected the solenoid's coil directly across the battery so that the contacts closed and current could flow through them to the starter motor. This demonstrates that the solenoid is not the cause of your problem.

The next step is to leave the jumper connected to the battery negative off and see if it cranks when you connect the positive jumper (cranking and "turning over" are the same thing; Don't worry about getting it to fire yet - one problem at a time).
  • If it does the problem is somewhere between the battery + and the red/yellow wire, perhaps a disconnected or broken wire but more likely a dirty Start button.
  • If not the problem is between the green/red wire and ground so you need to look at the neutral switch and the clutch switch.

BTW: What kind of technician are you?
From the looks of it, the yellow/red wire isn’t damaged. The only part I can’t see is the part that goes into the starter switch.
 

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'84 CX650E that is evolving into a GL500
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OK, you should at least understand enough about electrical to read wiring drawings. You would be amazed at some of the absolute misinformation some auto techs were taught and believe is true about electrical systems but we'll get you straightened out ;-)
And speaking of drawings, have you studied the one I posted? There are 2 switches and at least 3 wires between the solenoid's coil and the battery (it is simplified to explain the circuit so no connectors are shown) and the problem could be anywhere in that circuit (at least you can rule out the negative/ground circuit).

This is with the key in the ON position, right?

I just had a look at your pic and it looks like the harness is apart and probably a lot of it is missing. You might be better off shopping for a complete harness instead of messing around with that.

Does it have the original handlebar switch assemblies? Are they connected the way they should be? I wonder how many important wires the hack you got it from removed....

Re firing: What position is the kill switch in? If it is set to Off the starter motor will run but the ignition won't fire.
 

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Discussion Starter · #15 ·
OK, you should at least understand enough about electrical to read wiring drawings. You would be amazed at some of the absolute misinformation some auto techs were taught and believe is true about electrical systems but we'll get you straightened out ;-)
And speaking of drawings, have you studied the one I posted? There are 2 switches and at least 3 wires between the solenoid's coil and the battery (it is simplified to explain the circuit so no connectors are shown) and the problem could be anywhere in that circuit (at least you can rule out the negative/ground circuit).

This is with the key in the ON position, right?

I just had a look at your pic and it looks like the harness is apart and probably a lot of it is missing. You might be better off shopping for a complete harness instead of messing around with that.

Does it have the original handlebar switch assemblies? Are they connected the way they should be? I wonder how many important wires the hack you got it from removed....

Re firing: What position is the kill switch in? If it is set to Off the starter motor will run but the ignition won't fire.
I’d like to think I can read diagrams and know a fair amount. The guy before me removed all of the lights other than the head light and tail light. I might end up having to get a new harness. He said he “simplified it” but it’s not that way. At least to me. Got rid of the fuse box and everything. It is in the on position on the key. And in run on the start switch. I’m in the middle of cleaning the start switch (bigger pain than I thought it would be) but the contacts in it were all oxidized and gross. This week I will most likely be ordering a harness and a start switch.
 

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Discussion Starter · #16 ·
I’d like to think I can read diagrams and know a fair amount. The guy before me removed all of the lights other than the head light and tail light. I might end up having to get a new harness. He said he “simplified it” but it’s not that way. At least to me. Got rid of the fuse box and everything. It is in the on position on the key. And in run on the start switch. I’m in the middle of cleaning the start switch (bigger pain than I thought it would be) but the contacts in it were all oxidized and gross. This week I will most likely be ordering a harness and a start switch. I did look at your diagram and messed around with some stuff on it. It is not the stock front end. I’m fairly certain that this front end is off a Suzuki GSXR. No gauges or switches other than start switch
 

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Discussion Starter · #17 ·
OK, you should at least understand enough about electrical to read wiring drawings. You would be amazed at some of the absolute misinformation some auto techs were taught and believe is true about electrical systems but we'll get you straightened out ;-)
And speaking of drawings, have you studied the one I posted? There are 2 switches and at least 3 wires between the solenoid's coil and the battery (it is simplified to explain the circuit so no connectors are shown) and the problem could be anywhere in that circuit (at least you can rule out the negative/ground circuit).

This is with the key in the ON position, right?

I just had a look at your pic and it looks like the harness is apart and probably a lot of it is missing. You might be better off shopping for a complete harness instead of messing around with that.

Does it have the original handlebar switch assemblies? Are they connected the way they should be? I wonder how many important wires the hack you got it from removed....

Re firing: What position is the kill switch in? If it is set to Off the starter motor will run but the ignition won't fire.
Is there any companies that make these harnesses? Or do I just have to trust the one I buy from eBay works? Same for the start switch
 

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'84 CX650E that is evolving into a GL500
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Start is the button you press. Kill is the switch on top marked "OFF RUN OFF".

Simplified can be good if you know what you are doing and understand what you are working on. Unfortunately a lot of people have no idea so they remove wires just to make the harness skinnier with no thought about why a company like Honda would spend the time, effort and money to include those wires in the first place.
Honda used the same switches (with varying cable lengths &c) on a lot of models so aftermarket repros are available (you would need to make sure you get a right switch that is for models with points or Transistor amplifier Ignition (TI), not CDI models because CDI kill switches short the ignition while TI/points ones just turn the power off).
I don't know of any companies that make wiring harnesses for old bikes other than the odd custom place. Generally used ones are OK unless there is a melted wire or something like that.

Did you check for continuity between the coil and the switch and across the switch (in RUN) before you started taking stuff apart? And I assume you know to use real contact cleaner and not WD40 (leaves sticky residue) or brake or carb cleaner (can melt plastic parts) and you haven't sanded any contacts (particles of grit embedded in a contact will damage its mate).
 

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Discussion Starter · #19 ·
Start is the button you press. Kill is the switch on top marked "OFF RUN OFF".

Simplified can be good if you know what you are doing and understand what you are working on. Unfortunately a lot of people have no idea so they remove wires just to make the harness skinnier with no thought about why a company like Honda would spend the time, effort and money to include those wires in the first place.
Honda used the same switches (with varying cable lengths &c) on a lot of models so aftermarket repros are available (you would need to make sure you get a right switch that is for models with points or Transistor amplifier Ignition (TI), not CDI models because CDI kill switches short the ignition while TI/points ones just turn the power off).
I don't know of any companies that make wiring harnesses for old bikes other than the odd custom place. Generally used ones are OK unless there is a melted wire or something like that.

Did you check for continuity between the coil and the switch and across the switch (in RUN) before you started taking stuff apart? And I assume you know to use real contact cleaner and not WD40 (leaves sticky residue) or brake or carb cleaner (can melt plastic parts) and you haven't sanded any contacts (particles of grit embedded in a contact will damage its mate).
So I have some news about the bike. Was able to pull it in at lunch today and mess with it. After I rebuilt the start switch, it’s good. I don’t think I have power coming out of the rectifier. If I probe the black wire (in your simplified diagram) that is coming out of the rectifier with key on, it will crank off the start button. I didn’t know which yellow wire to probe coming out the alternator side of the rectifier. Could it be the rectifier that’s bad? Maybe the alternator?
 

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