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Lay a spanner across the two large terminals on the solenoid.
Whatever you lay across the terminals of the solenoid, make sure it's well insulated. I used a large screw driver and wore a thick rubber glove while holding the screw driver. It will likely spark a little if all the other circuits are working.

As others said, I would also first check the 30A main fuse located near the solenoid.
 

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1982 gl500
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General rule of diagnostics is "divide and conquer". This means finding something in the middle of the system you can test (starter button) - if the thing passes the test (gets power and switches some wire on when pushed) you know the issue is downstream between the test location and the part that isn't working, if it fails you know it is between the battery and the test-location. Then you keep dividing up the space you isolated the problem to until you find it.
Always check the basics first tho - fuses and things unplugged.
 

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Whatever you lay across the terminals of the solenoid, make sure it's well insulated. I used a large screw driver and wore a thick rubber glove while holding the screw driver. It will likely spark a little if all the other circuits are working.

As others said, I would also first check the 30A main fuse located near the solenoid.
You need a ground to get shocked. You can use a spanner, just don’t touch the bike anywhere with your other hand. Rubber gloves shouldn’t be needed.
 

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I was fixing an old Triumph 2000 on the side of the road once. Managed to bridge the starter solenoid with my metal watch band while reaching down the side of the engine. It stuck, the motor cranked {but wouldn't start} and it left a good burn on my wrist.

I've never worn a watch in the intervening 40 years.
 

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'84 CX650E that is evolving into a GL500
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You shouldn't get a shock from 12V DC but the tool you jump the terminals with could get hot from the current passing through it and burn you. (I was typing at the same time as Phreak but that is a good example of what I meant)
If you attempt this make sure the tool doesn't touch any other part of the bike. You do NOT want to short the battery.

The primary rule of troubleshooting is to look at the simple/obvious things first and once those are eliminated work through the system methodically, not to pick something at random and start messing around.

The most simple & obvious thing I can think of is does the electric system have power? Do any of the lights come on when you turn the key on? If not you need to find out why there is no power anywhere before you chase down a bunch of dead ends trying to figure out why it won't start.
The first thing I'd look at is the battery. You mentioned charging it but if you mean the one that was in the bike for 5 years without any attention/maintenance it probably can't hold enough charge to do much.
If you replaced the battery and the lights don't turn on the next thing to look at is the main fuse. As has been mentioned, the original "dogbone" type main fuses deteriorate over years of being exposed to the air to the point where hairline cracks can develop that prevent any current from flowing through them (I've even seen them crumble when touched). Even if yours looks perfect I would still recommend replacing it and don't fall into the trap of trying to use the spare because it is probably just as old. A blade fuse in an inline holder is definitely the best thing to replace it with.

Once you have power try again and let us know what happens.

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 as well as links in the signatures of several others who have replied) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
With your current problem I would also recommend getting the appropriate colour wiring drawing and maybe the Honda Wire Color Codes chart while you are there.

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).
 

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1980 Honda CX500
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Discussion Starter · #26 ·
Make sure you’re in neutral first. A spanner as already said or a screw driver will work to jump it. If you don’t know anything about electrics you might want to get more specific directions. Do you have a multimeter and know how to use it?
Yeah I have one and know how to use it I just have no idea where to test for this issue
 

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Discussion Starter · #28 ·
You shouldn't get a shock from 12V DC but the tool you jump the terminals with could get hot from the current passing through it and burn you. (I was typing at the same time as Phreak but that is a good example of what I meant)
If you attempt this make sure the tool doesn't touch any other part of the bike. You do NOT want to short the battery.

The primary rule of troubleshooting is to look at the simple/obvious things first and once those are eliminated work through the system methodically, not to pick something at random and start messing around.

The most simple & obvious thing I can think of is does the electric system have power? Do any of the lights come on when you turn the key on? If not you need to find out why there is no power anywhere before you chase down a bunch of dead ends trying to figure out why it won't start.
The first thing I'd look at is the battery. You mentioned charging it but if you mean the one that was in the bike for 5 years without any attention/maintenance it probably can't hold enough charge to do much.
If you replaced the battery and the lights don't turn on the next thing to look at is the main fuse. As has been mentioned, the original "dogbone" type main fuses deteriorate over years of being exposed to the air to the point where hairline cracks can develop that prevent any current from flowing through them (I've even seen them crumble when touched). Even if yours looks perfect I would still recommend replacing it and don't fall into the trap of trying to use the spare because it is probably just as old. A blade fuse in an inline holder is definitely the best thing to replace it with.

Once you have power try again and let us know what happens.

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 as well as links in the signatures of several others who have replied) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
With your current problem I would also recommend getting the appropriate colour wiring drawing and maybe the Honda Wire Color Codes chart while you are there.

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).
Thank you for all the info i appreciate it and just to clear up some things I charged the battery and it is awful but it held enough charge to turn all lights on but once start button is pressed nothing no click no sound at all
 

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'84 CX650E that is evolving into a GL500
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Yeah, the starter motor draws more current than everything else on the bike put together. It is pretty typical for a charger to tell you that an old battery is fully charged only to have it go flat as soon as there is a load on it.
Most people consider 5 years to be an acceptable life for a motorsports battery that is properly maintained during storage (either connected to a battery maintainer or re-charged every month) so the likelihood of being able to start it with a battery that has been neglected that long is pretty low. In fact, I'd say you are lucky if it didn't freeze, crack and leak acid all over everything in that time.
 

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Discussion Starter · #31 ·
Yeah, the starter motor draws more current than everything else on the bike put together. It is pretty typical for a charger to tell you that an old battery is fully charged only to have it go flat as soon as there is a load on it.
Most people consider 5 years to be an acceptable life for a motorsports battery that is properly maintained during storage (either connected to a battery maintainer or re-charged every month) so the likelihood of being able to start it with a battery that has been neglected that long is pretty low. In fact, I'd say you are lucky if it didn't freeze, crack and leak acid all over everything in that time.
The battery was new when the previous owner had this problem but it wouldn’t hurt to start there
 

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In that case he probably parked it because of a different problem. But you will never be able to find it until you have a battery that works....
 

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Does your headlight go completely out when hitting the start button? Sometimes on these old bikes switches can get sticky and/or corroded. I sprayed some penetrating oil inside the switch via the starter button, while doing thumb exercises with the starter button. Eventually, it worked!
Also, I have noticed on my '81 GL500, I have to pull in the clutch handle before it'll turn over.
I also noticed that after I installed a new bat tree? (haven't ridden much in the past 3 er 4 years) I no longer have to pull in the clutch handle.
Go figure, eh?
 

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1) Contact cleaner is the only thing you should ever spray on electrical contacts.
2) If you have to pull the clutch lever to get it to start with the transmission in neutral you have a problem with the neutral light or the diode. Replacing the battery probably had nothing to do with the actual problem.
3) We have established that at least part of what is going on here is that the battery can't hold enough charge to run the starter motor.
 

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Discussion Starter · #36 ·
Does your headlight go completely out when hitting the start button? Sometimes on these old bikes switches can get sticky and/or corroded. I sprayed some penetrating oil inside the switch via the starter button, while doing thumb exercises with the starter button. Eventually, it worked!
Also, I have noticed on my '81 GL500, I have to pull in the clutch handle before it'll turn over.
I also noticed that after I installed a new bat tree? (haven't ridden much in the past 3 er 4 years) I no longer have to pull in the clutch handle.
Go figure, eh?
No head light atm but I will try that tonight with the new battery
 

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BTW, the Start button on these bikes (& a lot of other Hondas) have 2 sets of contacts, one set to feed power to the solenoid's coil do that the solenoid can send power to the starter motor and the other set to interrupt power to the headlight so that more of the battery's power is available to the starter motor.
 

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I would have tested for voltage at the solenoid's coil when the button is pressed before I started taking things apart. Most start button problems aren't caused by the actual button.
 

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I’m trying to navigate through the diagram sent above but I’m having a hard time understanding the wiring diagram. Im not technically incline with wiring at all
Reading wiring diagrams is like following a road map. Your journey starts at the + battery terminal. Follow the line from the battery to your point of interest, in this case the start button. Follow through the start button and so on. You must eventually return to the - battery terminal or a ground connection.
 
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