Welcome aboard!
You are about to become an electronic technician.
No juice, no lights is not the charging system but a wiring, connection issue. "somewhere"
A couple pics of the bike will really help us, all stock or "re-engineered"?
Start by looking at connections.
#1 Ground strap from battery to frame. Remove, flex, looking for gray dust at the ends, clean frame reinstall.

#2 The the fuse box area is next, seldom intact by now, the little metal fuse holders rot and fall apart.
A simple diagram of the basic wiring.
View attachment 237929
the physical fuse box layout
View attachment 237930
power goes from battery to main fuse ,then up to ignition switch, (the switch CAN have corrosion issues inside) Hawaii, salty air....., then; back to fuse box to the other three fuses.
start at the battery and test till you find where the power peters out.
a good idea to print this out.
View attachment 237932
Poster size is handy....
Where is the main fuse box on my 75?? All stock. I see a fuse holder and one fuse inside right side cover but thats it. Thanks again for everything
 
Where is the main fuse box on my 75?? All stock. I see a fuse holder and one fuse inside right side cover but thats it. Thanks again for everything
That one fuse is all you have, the fuse blocks didn't come till the special model was introduced.
I might be repeating, but removing the ground strap between battery and frame, checking for corrosion at the connectors, cleaning the frame to shiny metal where it bolts on, is something I do very early on every bike that comes through here. I've found a BUNCH of rotten ground straps, creating lots of issues...............
We're glad to help, keep the cards and letters coming...
 
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That one fuse is all you have, the fuse blocks didn't come till the special model was introduced.
I might be repeatiing but removin t he ground strap between battery and frame, checking for corrosion at the connectors, cleaning the frame to shiny metal where it bolts on, is something I do very early on every bike that comes through here. I've found a BUNCH of rotten ground straps, creating lots of issues...............
We're glad to help, keep the cards and letters coming...
Great. Yes all you mentioned above in my bike is spotless. I get what youre saying though
 
What is 12.6 surface volts on a battery
That one fuse is all you have, the fuse blocks didn't come till the special model was introduced.
I might be repeatiing, but removing the ground strap between battery and frame, checking for corrosion at the connectors, cleaning the frame to shiny metal where it bolts on, is something I do very early on every bike that comes through here. I've found a BUNCH of rotten ground straps, creating lots of issues...............
We're glad to help, keep the cards and letters coming...
Would 12.6 surface volts on a battery after 48 hours be OK or is that a sign of a bad battery. It was fully charged at about 13 V right off the tender 48 hours ago and this is what it is today, 12.6.
 
Hey jim, i just picked up a 1980 xs650, its my first bike. It worked fine when he showed me, but had to kickstart it. The battery died between us talking and so wasnt able to test ride it but picked it up anyway. Now its been replaced with 2 different batteries, and still nothing, no lights, no turn over. Im starting to think it’s the stator and am wondering if this deal will come with a stator or just the rotor? If not do you or anyone you know have a stator to sell?
No, just the rotor. But as JP points out, it's highly unlikely the stator's failed.
Follow Gary's lead, post some pics and we'll get it sorted.
 
What is 12.6 surface volts on a battery

Would 12.6 surface volts on a battery after 48 hours be OK or is that a sign of a bad battery. It was fully charged at about 13 V right off the tender 48 hours ago and this is what it is today, 12.6.
That's near perfect! - on lead acid & AGM types
 
I'd call it probably within normal deviation.
Maybe not brand new but serviceable.

https://shop.advanceautoparts.com/r/advice/car-maintenance/car-battery-voltage-range
If we haven't mentioned it; a volt meter up where you can see it while riding is VERY popular with motorcyclists that aren't big on pushing their bike on deserted rural highways.
A combo phone charger voltmeter up on the bars kinda useful specially if you use the phone GPS much...
I've got this one built into my dash but little strap on the handlebars voltmeters are common, cheap, and useful.
led indicators red.jpg
 
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What is 12.6 surface volts on a battery

Would 12.6 surface volts on a battery after 48 hours be OK or is that a sign of a bad battery. It was fully charged at about 13 V right off the tender 48 hours ago and this is what it is today, 12.6.
Surface volts are excess volts above what the normal charge would be. It's called that because the excess voltage occurs just on the surface of the plates and not in the plates.
Also known as "surface charge".... your 13v is above the normal range... a surface charge.
12.6v after 48hrs is the sweet spot. You're good.
 
That's near perfect! - on lead acid & AGM types
But this 12.6 V will be right at about 12.5 or maybe 12.48 in a day or two. At that point I hook a tender up to it. That’s not a good thing though correct, it should never drop below 12.5 within a week of being fully charged.
 
But this 12.6 V will be right at about 12.5 or maybe 12.48 in a day or two. At that point I hook a tender up to it. That’s not a good thing though correct, it should never drop below 12.5 within a week of being fully charged.
All batteries discharge over time when not being used... some faster than others, but they all do. that's kinda why tenders were invented. ;)
Down to 12.5 after a week isn't cause for concern.
 
I think that's ok. If it gets more serious, like near 12 in a week, we can check for parasitic draw when off. For the task at hand - charging system test - you're good to go...
 
Madness has been dropping below 12 after few weeks this winter, she's about due for a new battery.
:twocents: I'll run an automatic charger / tender for a day now and then over the long off season in the great white north but don't leave them on the battery full time.
I tend to get 5-6 years life out of plain old lead acid batteries.
 
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All batteries discharge over time when not being used... some faster than others, but they all do. that's kinda why tenders were invented. ;)
Down to 12.5 after a week isn't cause for concern.
Gotcha. I’ve heard that leaving them on a tender is also bad. Somebody said that’s where the corrosion in my rectifier came from. I highly doubt that’s the case but what are your thoughts about a battery constantly on a tender. One that maintains the voltage and doesn’t overcharge of course.
 
Th
Howdy - Jim will be along later, but in the meantime:

It's unlikely to be the stator; they are generally very reliable and don't drain the battery when failed. You can test all of the system (incl. stator & rotor) with a common multimeter and we'll help ya do that...
Thanks a lot! I don’t get off duty until tomorrow morning and will start checking everything then!
 
Thanks
Welcome aboard!
You are about to become an electronic technician.
No juice, no lights is not the charging system but a wiring, connection issue. "somewhere"
A couple pics of the bike will really help us, all stock or "re-engineered"?
Start by looking at connections.
#1 Ground strap from battery to frame. Remove, flex, looking for gray dust at the ends, clean frame reinstall.

#2 The the fuse box area is next, seldom intact by now, the little metal fuse holders rot and fall apart.
A simple diagram of the basic wiring.
View attachment 237929
the physical fuse box layout
View attachment 237930
power goes from battery to main fuse ,then up to ignition switch, (the switch CAN have corrosion issues inside) Hawaii, salty air....., then; back to fuse box to the other three fuses.
start at the battery and test till you find where the power peters out.
a good idea to print this out.
View attachment 237932
Poster size is handy....
Thanks gary! Yeah it is “reengineered” when it was converted to a cafe racer he removed the fuse box and now i cannot find the main fuse for the life of me.

I get off duty tomorrow and will check it then, i want to replace the wiring harness because the wiring is kind of a mess, so this will teach me a lot!

Ill post pics tomorrow!
 
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