Flat battery bike died

On the bikes that use the separate regulator and rectifier, unplugging the regulator does remove the power to the rotor.
On those bikes power goes to the regulator then to rotor, then ground.
On the later combo reg/rec power goes to the rotor, then to regulator and the regulator grounds the rotor.
Unplugging the big plug in the wire bundle coming from the stator just above the engine works on all years.
Leo
 
XSLeo said:
On the bikes that use the separate regulator and rectifier, unplugging the regulator does remove the power to the rotor.
On those bikes power goes to the regulator then to rotor, then ground.
On the later combo reg/rec power goes to the rotor, then to regulator and the regulator grounds the rotor.
Unplugging the big plug in the wire bundle coming from the stator just above the engine works on all years.
Leo
Click to expand...

Which one is the '79 Special then?
And why exactly does it have to be unplugged?
At the moment its all connected and the red light is showing on the dash.
 
The XS alternator for all years use a powered field. In this case the rotor. The amount of power coming out of the stator is determined by how strong the rotor (magnetic) field strength is. This field strength is controlled by the regulator. If voltage is low, the regulator increases the voltage to the rotor, increasing the field strength, which increases the output from the stator. So, in a system like this, it's the regulator that sends power to the rotor. Disconnecting the regulator as was recommended before will kill power to the rotor. The brown/green/black plug you described earlier. Brown is power in to the regulator, black is the ground, and the green is power out to the rotor for energizing the field. Pull it.
 
That's only true up to '79. In '80, they reversed the brush wiring. Constant (switched) power is fed to the inner brush. Ground is fed to the outer brush by the regulator, switched on and off to control charging output. So, just unplugging the regulator on an '80 and later system may not stop the rotor from draining off power if it's shorted to ground.
 
Thanks..mines a 79 Special so Ill unplug the regulator.
Not being electrically inclined I still dont understand why, in basic terms, why I need to unplug anything?
Cos itll blow my fuse and strand me roadside even with charge in battery?
Or
Cos if I leave it connected itll flatten the battery quicker?
Or both....
 
If the rotor is shorting (grounding) out, it will drain power out of the battery faster than just operating the ignition alone.
 
5twins said:
In '80, they reversed the brush wiring. Constant (switched) power is fed to the inner brush. Ground is fed to the outer brush by the regulator, switched on and off to control charging output.
Click to expand...
Thank's 5twins. I didn't know they changed it in '80.
 
XSLeo said:
On the later combo reg/rec power goes to the rotor, then to regulator and the regulator grounds the rotor.
Unplugging the big plug in the wire bundle coming from the stator just above the engine works on all years.
Leo
Click to expand...
My apologies Leo, didn't realize they changed it when they went to a single unit. Learn sumpin' new every day....
 
Thanks and apologies...geeze you blokes have much better manners than over on the Victory forum.
Nice to see....and thanks
Other forum seem to be at each others throats over politics and religion all the time, no tolerance or balance.
Thankfully those subjects are Verboten here and it shows ( give yourselves a pat on your backs)

Mines 3/79 so Im disconnecting at the reg before todays ride.
Would need to remove air filters and carbs to get at main connector so thats a relief.

Hopefully an enjoyable test ride coming up
 
motorbikerx said:
thinking of throwing a small car battery in one side of throwover saddlebags and a brick in the other to balance weight.
Connect it up in series to my underseat battery for extra range.
Click to expand...

Well its fairly heavy at 9kgs even though its not big .
What do you electically minded think of a solar battery charger say 2.4 watts on the back seat connected for daylight running no lights except the occasional brakelight...
Would it stop me being stranded?
Got my 4amp charger in the saddlebag so I can plug in at 240volt when possible..
Desperate to ride hey!
 
motorbikerx said:
Well its fairly heavy at 9kgs even though its not big .
What do you electically minded think of a solar battery charger say 2.4 watts on the back seat connected for daylight running no lights except the occasional brakelight...
Would it stop me being stranded?
Got my 4amp charger in the saddlebag so I can plug in at 240volt when possible..
Desperate to ride hey!
Click to expand...

I can answer my own question from reading up on the 2.4 watt solar charger says not to use it with ignition on as surges can damage the charger.
 
sure take an extra battery with you but instead of wiring them in parallel I would recommend using the on board battery until the engine starts to die on you then add the extra battery .
That way you won't suddenly find yourself stranded with no warning and no backup battery ..;)

Oh and don't wire your batteries in series or you'll get 24v and blow everything

Take a run out locally around home base and see how many miles you get on a full charge.



It doesn't need to be a car battery most small 12v batteries will do . The ignition takes very little current from the battery ,its all the ancillaries like lighting that will drain the battery quickly. You could even use any 12v Li-ion battery from a portable drill to start and run the bike. obviously make sure the charging system isn't connected if you use a Li-ion battery.
Pull the front and rear light bulbs or disconnect them for daylight running and leave plenty of time to brake with the front brake so you are not constantly using the rear brake light .
 
Thanks...not gonna bother pulling or disconnecting bulbs.
Just wont turn them on and Im not a constant braker as I usually leave a good gap and use gears to slow and Im a front braker anyway unless conditions dictate I need rear.
The half hour talcum powder ride only needed 5 mins on my cheap little charger to be back in the green again.
Ill hung for some cheap light 12v batteries for backup and like you say leave em for reserve
 
it would be handy if you add the model year and spec of your bike to your profile so that everyone can see it at the bottom of each post at a glance instead of having to search for it .;)
Don't forget that late models have the stop light wired to both front and rear brakes and I thought that the headlight came on automatically by relay whilst running on at least some model years ?
 
Which models dont have brake lights off both front and rear brakes?
Thats a new one on me...
Never owned an XS650 that I couldnt kill the headlight on either.
Yes Ill add my year model just tell me htf to do it, I just got here, wheres the instruction manual?
 
motorbikerx said:
Which models dont have brake lights off both front and rear brakes?
Thats a new one on me...
?
Click to expand...
you're right I just checked all the schematics for all years they all have front brake stop light switches my bad I should have checked first
....That'll teach me for spending so much time trying to help a fellow biker :rolleyes:

motorbikerx Looking looking looking ...wheres this bike info you speak of?

Try looking in your 'profile' you can't expect us to do everything for you;)
 
In 1978, Yamaha added a safety relay for the headlight that automatically turned it on once the bike was running. Or actually, once the relay sensed a charge output from the alternator. Since you're not charging, you shouldn't have to worry about that, lol.
 
5twins said:
In 1978, Yamaha added a safety relay for the headlight that automatically turned it on once the bike was running. Or actually, once the relay sensed a charge output from the alternator. Since you're not charging, you shouldn't have to worry about that, lol.
Click to expand...

That was in the US
We didnt get headlights forced on us here till later.
More daytime visibility yes.
But its still nice to have choices.

Just yesterday out test riding I had no less than 3 cars pull straight out in front of me , then when they did finally see me...they wave!
 

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