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1981 cx500 custom
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Discussion Starter · #1 ·
Hi folks
A year ago i procured an 81 cx500. With the help of a local professional, she is running and riding good.
My issue now is the charging system.
Now, to be brunt, i am no mechanical and sometimes struggle to change the oil on my mower.
The battery doesn't hold a charge, and when i put the ol multi meter on it, it doesn't register and increase in volts when running.
So, i guess i am looking at a stator and regulator?
I'll take the seat off and check what i can at the connections.
If anyone has been in similar straits,
did you drop rhe engine yourself and learn in process, or bite the bank account and take the repair to a shop?
All feedback is greatly appreciated.
馃槉
 

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For now, take the seat off and find the CDI box. Directly behind it are three connectors.

You are after the 3 wire connector with the yellow wires.

Disconnect that and probe the side leading to the motor on all combinations of the three pins with a multimeter set to ohms.

You should have full continuity between all pairs of pins. Now probe them while grounding your other probe. There should be no reading here.

So continuity between combos of pins - good.

Continuity between pins and ground - bad.
 

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Welcome @Pinalski. You've come to the right place for CX/GL help. Try fixing it yourself (with the help of the forum) before you take to a "professional'. Hundreds of years of experience here!
 
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Registered
1981 cx500 custom
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Discussion Starter · #4 ·
For now, take the seat off and find the CDI box. Directly behind it are three connectors.

You are after the 3 wire connector with the yellow wires.

Disconnect that and probe the side leading to the motor on all combinations of the three pins with a multimeter set to ohms.

You should have full continuity between all pairs of pins. Now probe them while grounding your other probe. There should be no reading here.

So continuity between combos of pins - good.

Continuity between pins and ground - bad.
Thanks,
I found a video series on YouTube from UrbanMonk....
now if i can just fi d tve ohms setting on the multimeter.
馃ぃ
 

Registered
1981 cx500 custom
Joined
12 Posts
Discussion Starter · #7 ·
I won't knoe the proper verbiage-
When testing pin to pin:
. 71
.61
.77
when grounded to chasis
1.51 on each pin.
驴No bueno?
 

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1981 cx500 custom
Joined
12 Posts
Discussion Starter · #9 ·
Well, with the motorbike anyways.
馃ぃ
I've bedn calling around for a "guestamate"....
which no doubt will be substantial.
None of the shops want to take it on.
I might be forced to do the job myself.....
out of necessity.
 

Super Moderator
Joined
5,797 Posts
I won't knoe the proper verbiage-
When testing pin to pin:
. 71
.61
.77
when grounded to chasis
1.51 on each pin.
驴No bueno?
What reading do you get with the meters probes touching each other, not touching each other?
 

Registered
Joined
2,979 Posts
Hi folks
A year ago i procured an 81 cx500. With the help of a local professional, she is running and riding good.
My issue now is the charging system.
Now, to be brunt, i am no mechanical and sometimes struggle to change the oil on my mower.
The battery doesn't hold a charge, and when i put the ol multi meter on it, it doesn't register and increase in volts when running.
So, i guess i am looking at a stator and regulator?
I'll take the seat off and check what i can at the connections.
If anyone has been in similar straits,
did you drop rhe engine yourself and learn in process, or bite the bank account and take the repair to a shop?
All feedback is greatly appreciated.
馃槉
People will "hate" me for this...
The FSM is your go to...
But if you are new to mechanical work, Haynes/Clymer might explain the "process" more fully...
(used a Haynes for my first (points ignition) CB250...pulled the carbs, dismantled, cleaned, balanced etc...the Honda shop telling me the carbs were spot on, when they next had the bike....)
Just dont use the wheel spindle to pull that fan......

Youtube or electronic websites also cover "how to use a multimeter/bulb tester" for basic electrical work...
or see if you can borrow this.......
 

Registered
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People will "hate" me for this...
The FSM is your go to...
But if you are new to mechanical work, Haynes/Clymer might explain the "process" more fully...
(used a Haynes for my first (points ignition) CB250...pulled the carbs, dismantled, cleaned, balanced etc...the Honda shop telling me the carbs were spot on, when they next had the bike....)
Just dont use the wheel spindle to pull that fan......

Youtube or electronic websites also cover "how to use a multimeter/bulb tester" for basic electrical work...
or see if you can borrow this.......
I don鈥檛 鈥渉ate鈥 you, just disagree. The factory service manual is very easy to read and follow. No reason to muddy the waters with an inferior manual. The only exception would be if you wanted color wiring diagrams.
 

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I don鈥檛 鈥渉ate鈥 you, just disagree. The factory service manual is very easy to read and follow. No reason to muddy the waters with an inferior manual. The only exception would be if you wanted color wiring diagrams.
I agree the FSM to me now seems a easy read.
But when I got that first bike at 16years old...hadn't even changed oil in the mower.
Back then tho', pre-internet, it was hard to get a free FSM....unlike here at the Forum. (I think my last hardcopy FSM was over $100 in the 1980s....)

If the OP finds the FSM logical, no need for the Haynes CX manual (agreed) but I'd recommend their basic electrical manual I linked to....
 

Premium Member
1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Welcome, Pinalski!
If you have basic mechanics' tools and any amount of mechanical aptitude, you can handle this. Just take your time and ask questions if you're unsure of something. We've all had a first time at this, and in every case, it helped us become better mechanics.
 

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1981 cx500 custom
Joined
12 Posts
Discussion Starter · #17 ·
This is a basic question.
Since the system allows the machine to run on a dead battery,
will it provide any juice for the lights and horn.
Portable battery packs are tiny now....
enough to start the bike,
but if i ride it to the coffee shop,
will there be any electronics for the trip back?
 

Super Moderator
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5,797 Posts
Simple answer is no. There are two parts to the cx500 stator. One part generates electricity to recharge the battery, which powers the lights and horn. If your battery is dead because the part of the stator which supplies power to the battery has failed there will be no power available for the lights, horn etc. The other part generates higher voltage electricity to power the ignition system which is why the bike will still run.
 

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1981 cx500 custom
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Discussion Starter · #19 ·
Well.....
rat farts!
馃ぃ
I think packing an extra battery for the return trip is a bit much.
Until i get the parts and courage to rip into this project, i guess I'll be limited to little runs around the neighborhood.
 

Super Moderator
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Push start the bike and use the battery pack to run your lights or, if the bike's battery holds a charge use that and just recharge when at home.
 
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