Alternator Disable Mod.

I thought of a new question about this "disable the alternator until started" issue:

If I use a method, any method, to disable the rotor field windings until started, does the yellow wire going out of the stator still generate it's 4 volts or more to trip the safety relay? Or does it need the rotor field to be hot?

I don't think it would be good for my safety relay to be rendered inoperative just to conserve the amperage the field draws!
 
Wasn't happy with starter run on without the relay.
 
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Wasn't happy with starter run on without the relay.
Get a faster finger. :boxing:

I don't think it would be good for my safety relay to be rendered inoperative just to conserve the amperage the field draws!

Fwiw... once started, the safety relay acts normally. IE.... if you accidentally hit the start button, nothing happens... it's locked out. And that, after all is the purpose of the relay.
 
Gotta beg to differ on this. I really think it was added to prevent starter overrun. My sample size is small but I removed the relay and reinstalled it a couple days later. They don't make (my?) fingers fast enough at least on that bike, I made the effort .
ps prollum went away as soon as relay went back in. Not a prob on your bike Jim?
 
Ha ha, thanx Jim.
But, that's not where the "noise" is.

Need a chalkboard, and a large room (for arm waving and flailing) to explain it...

Drop on by Steve - I work at a university so large rooms with chalk boards and a lot of arm waving....are a specialty! :rock:
 
Not a prob on your bike Jim?
Without re-reading this thread and the SG's .... I'm guessin' I forgot to mention it, but I tested it both ways, with and without the disable mod active. On the SG I get a consistent run on of about 1 to 1-1/2 secs. No discernible difference between with or without.
 
Finally got around to this.

From post #14:
https://www.xs650.com/threads/alternator-disable-mod.53271/post-630144

Last week, I decided to intercept the brown power wiring to the regulator, at the harness connector, with a simple toggle switch.

20230501_RotorSwitch1.jpg

20230501_RotorSwitch2.jpg

I guess that I should've painted the switch bracket black.

20230501_RotorSwitch3.jpg

Switch off before starting, then on after startup.
So far, the bike has been a "first kick" starter...
 
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Switch off before starting, then on after startup.
So far, the bike has been a "first kick" starter...

Ain't seen you 'round these parts for a spell. Yeah... old bikes an' old men... we take every advantage we can. :wink2:

Don't be a stranger Steve...
 
Just food for thought Steve. I don't know if you're in the habit of runnin' with the headlight on (not required on pre '75 in Texas) but if you are, you could run the headlight switch to a relay and have the relay power both the regulator and headlight.

Switch the headlight off for start: no charge or headlight power lost.
Switch the headlight on: Charging and headlight circuits energized.

One less switch to turn on.... or forget to turn on... :whistle:
 
Don't be a stranger Steve...

But..., but..., "strange" is my forte'.

... run the headlight switch to a relay and have the relay power both the regulator and headlight...

That's a great idea there, Jim.

However, I run with the headlight off during the day.
For some reason, the early charging system is weaker than the later models. At idle, headlight off, it barely puts out enuff to keep the bike running. With headlight "on", or a turn signal "on", power is pulled from the battery. Which tends to annoy the ignition system.

Switching to LEDs should help this... :D
 
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