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Discussion Starter · #1 ·
Today I pressed the starter button and got nothing. So I pulled in the clutch lever and it started. The connection under the seat from the neutral safety switch was good so I figured something was up at the switch even though the neutral light was on. Upon trying to remove the 7mm nut, the wire turned with it and with very little force it broke off.
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When I tried to remove the nut, it just spun but not on the threads. It was as though the internals of the switch were turning with the nut. Is that supposed to happen?
Is it possible for the neutral light to light up and still have a problem with the neutral safety switch? The wire where it connects to the eyelet does not look too good. Could it have provided enough ground for the light but not the starter relay?
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Any ideas as to how to proceed with pulling the wire? Hate to try to fix it in situ.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Just crimp on a new ring terminal. Easy fix.
 
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Discussion Starter · #3 ·
I found lots of helpful info here where Bearman1 had the same issue:
Neutral Switch Troubles
Perhaps most helpful was Reg post #6 in which he states:

"...the neutral light only needs milliamps to glow while the
solenoid needs about 4 amps the operate
It has to be grounded via either/or the neutral switch or clutch switch
If the neutral switch is developing a high resistance due to wear or crap
this will inhibit the solenoid function
the fact the clutch switch enabled it suggests this increased
the current path and flow and operated the solenoid."

So a poor connection at the switch can be good enough to effectively ground the neutral light so that it lights up but not good enough to ground the solenoid so as to operate the starter motor. Given the appearance of my wire, it could have been making just such a connection. Good to know. (Not surprised that I forgot participating in that thread ten years ago when I can't remember 10 minutes ago.)

Still wondering how to loosen and tighten the 7mm nut on the neutral switch since the threaded part it goes onto spins with the nut. Even if I get it off I still need to tighten it unless snug is supposed to be good enough.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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There should be a hex base on the switch. Either 14 or 17mm, if I remember right.
There should be a split lock washer under the small nut. It shouldn't be tight enough to back out the switch.
 
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Discussion Starter · #5 ·
The hex base is 14mm. I used a 7mm wrench on the small nut. Problem is, the nut just turns, left or right, won't loosen or tighten. It also turns independently of the small protrusion at the bottom:
Household hardware Nickel Auto part Bicycle part Metal

It could be messed up. My ohm readings for the switch bounced all over the place, although I was having difficulty holding the meter leads in place. I'd like to know if the threaded part that the nut goes onto is supposed to remain stationary. If it is, it doesn't look like it would take much to over tighten and break it loose.
 

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Discussion Starter · #7 ·
Thanks. And for those who may not be aware, engine oil will come out of the hole where the switch goes, easily over a quart. I had just topped off and now nothing shows on the dipstick.
 

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'84 CX650E that is evolving into a GL500
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I have heard of the contacts in GL1000 neutral switches (which are actual switches) becoming fouled and acting up but the neutral "switch" on the CX'GL500/650 is actually a spring loaded contact that touches part of the transmission to complete the circuit to ground and they tend to be self cleaning.

Today I pressed the starter button and got nothing. So I pulled in the clutch lever and it started.
<<<
Is it possible for the neutral light to light up and still have a problem with the neutral safety switch?
This sounds like the classic symptom of a failed starter circuit diode to me. As you can see in the drawing below the solenoid's coil can connect to ground either through the clutch switch or through the neutral switch via the diode (the diode's job is to allow that without having the neutral light turn on whenever you disengage the clutch).
If the neutral switch (or the wire to it) fails the engine won't start unless the clutch is disengaged AND the neutral light won't light.
Diodes usually fail in open circuit mode and when that happens the neutral light works normally but the solenoid's coil can't connect to ground through the neutral switch. (If the diode failed in short circuit mode the neutral light would light whenever the clutch was disengaged.)

Rectangle Schematic Font Parallel Slope


As for the nut not coming off, are you sure the part that it threads onto is turning or have the threads stripped? While I don't doubt it is possible for the insides to let go and turn within the housing I would expect that stripping those threads would be more common.
If the threads are stripped you might be able to get the nut off by gently pulling on it while turning it with pliers. If the ends of the threaded stud are in good shape you might be able to get it to hold the new ring lug by adding a washer and using a fresh nut.
If the stud is turning with the nut you will need a new switch.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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You're over analyzing, Bob. I the the broken ring terminal is the more obvious fault.
 

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I think I have a spare neutral sender from when I swapped the rear cover on my 650. I'll see if I can find it.
 

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I thought about it for a while before posting. The neutral bulb should draw about 1/4A so if the bulb lit up brightly the switch should have been able to pass enough current for the solenoid's coil.

And the ring lug broke when he turned the nut and it moved with it.

I'm pretty sure the switch needs to be replaced, but only because it was damaged by the nut being corroded onto the stud and turning the inside parts of the switch during the attempt to disconnect the wire.
I will be surprised if the diode doesn't turn out to be the actual cause of the problem.
 

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Discussion Starter · #12 ·
I think I have a spare neutral sender from when I swapped the rear cover on my 650. I'll see if I can find it.
Thanks Randall but your offer caused a light to go on and I have two covers that I won't be using and each one has the switch in them.
While I don't doubt it is possible for the insides to let go and turn within the housing I would expect that stripping those threads would be more common.
The threads turn too.
I will be surprised if the diode doesn't turn out to be the actual cause of the problem.
I thought about the fact that the neutral light was always bright when the problem occurred, that it did not even flicker, nor has it ever. The switch needs replacement and the wire repaired. I'll look into the diode also.
 

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'84 CX650E that is evolving into a GL500
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When you get the new switch in the diode's condition will be easy to determine. Or if your meter has a diode test setting you can simply unplug it and test it now.
 

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Discussion Starter · #14 · (Edited)
Repaired the wire and installed working switch. All is well. Neutral light and solenoid functioning as they should.

I pulled the diode and tested it using the diode test function on my multimeter. Having never tested one before, I put the positive lead on the circled terminal and the negative lead on the other one I get a result of 547. The meter shows the number one when the leads are reversed. That is to say nothing happens, the screen remains as it was before connecting the leads.
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Since a spare diode tested the same, I'm guessing the one from the bike is working. Based on my test results, is it?

Keep in mind that the problem is intermittent. Once a week or so I might have to push the start button several times before the starter motor turns.

I'm confident I eliminated the starter switch/button as the problem. I tested and found that I was getting power to the solenoid when the start button was pushed but the starter motor did not turn. It was then down to the solenoid itself or the grounding of it. It wasn't until yesterday that I thought to pull in the clutch lever when the problem occurred. The bike started right up and my focus turned to the switch, the wire and then the diode.

Unless someone has a better idea, my approach at this point is to see if fixing the wire and installing a good switch fixes the problem. If someone will confirm that my test numbers are in spec I'll continue to use the same diode I have been using. If I have no more problems then problem solved. If a diode can fail intermittently then a failing diode remains a possibility.
 

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'84 CX650E that is evolving into a GL500
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I think your meter is telling you the diode is OK. What do the meter's instructions say about using the diode test function?

If the diode is OK and the neutral switch is OK and it still intermittently won't start the next suspect would be the wires that connect the diode to the circuits.
 

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I had exactly the same thing for a while with my blue 500C. everything checked out but it continued to be picky about starting from the button.

One day it wouldn't start at all and this is what it took to uncover the actual problem.

The yellow/red wire had at some point been probed with a circuit tester in the steering flex zone.

The wire internally corroded from this and eventually broke totally.

Repaired the wire {had to remove several inches of blackened wire} and never another issue.
 

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Discussion Starter · #17 ·
Thanks everybody. Bob, I don't have the instructions for my meter but I think I read where something around 500 was a good reading for a diode in general. I'll look into that some more. I'd like to know what a good reading is for our diodes.

I may or may not have fixed the problem. I will say that the eyelet or ring at the end of the wire broke off rather easily, like "wow, that's not right" easy.
 

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Discussion Starter · #19 ·
You should always save the manuals from tools & equipment for future reference.
I might have done so if it hadn't been written in subatomic script. I found the manual for my multimeter here: https://manuals.harborfreight.com/manuals/63000-63999/63759.pdf
The instructions for testing a diode:
Font Parallel Number Document


"...displayed in milivolts", in my case 547mv or .547 volts. That falls within range if the following applies:
Tool Watch Font Bicycle part Automotive lighting

This applies to diodes in general and I think applies to the one in question assuming it's a Silicon diode.
 

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'84 CX650E that is evolving into a GL500
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Yep. I'd say yours is probably OK.

FWIW, I have a folder on my network drive with manuals I've downloaded for all sorts of items we have that either didn't come with one or it was too small to rad (don't you just when they assume everyone has teenage eyes?)
 
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