Bike dying when using turn signals

[Rich82GS750TZ]

https://www.thegsresources.com/_forum/showthread.php?253112-Cheap-NOS-Compufire-stock-on-EBAY

[mcquillr]

B0D9B4BC-BE54-4B1E-8742-83E2FAEB98BF.jpg

As a semi-side note, I am trying to understand my bike’s wiring diagram. I have begun to annotate the factory diagram in color, but I’m not understanding how the regulator is functioning in this circuit. It doesn’t appear to be in-line with the battery. I must be missing something here unless the regulator is drawing current away from the stator circuit to regulate he voltage?

Image Link: http://m.imgur.com/a/I38PayM

[Uncamitzi]

[ATTACH=CONFIG]56196[/ATTACH]

As a semi-side note, I am trying to understand my bike’s wiring diagram. I have begun to annotate the factory diagram in color, but I’m not understanding how the regulator is functioning in this circuit. It doesn’t appear to be in-line with the battery. I must be missing something here unless the regulator is drawing current away from the stator circuit to regulate he voltage?

Image Link: http://m.imgur.com/a/I38PayM

Power is generated at the stator.. 3 phase (the three wires from the stator) feed the rectifier/regulator converting the AC voltage to DC power.. from there to the fuse box and to the battery to charge.

[mcquillr]

Yes but in the wiring diagram it looks like the regulator is connected directly to one of the phases instead of being inline with the rectifier and then the battery.

[mcquillr]

Actually, I think I was thinking about this wrong. The voltage off the stator is somewhere around 75V and once it leaves the rectifier circuit it should be around the proper range (13-14V) to charge the battery. If the battery is full, the regulator begins to draw power from the rectifier circuit straight to ground. If the rectifier can't dissipate the heat fast enough then that heat is passed off back to the stator (this is what can cause it to blow up).

Did I get it right this time?

[Brendan W]

[ATTACH=CONFIG]56196[/ATTACH]

As a semi-side note, I am trying to understand my bike’s wiring diagram. I have begun to annotate the factory diagram in color, but I’m not understanding how the regulator is functioning in this circuit. It doesn’t appear to be in-line with the battery. I must be missing something here unless the regulator is drawing current away from the stator circuit to regulate he voltage?

Image Link: http://m.imgur.com/a/I38PayM

Hard to read the diagram but....
The output of the regulator is what runs the bike, not the battery. The positive r/r output is teed into the main power line and the negative receives the returning currents as directly as possible or should do. That leads on to the idea of single point grounding, SPG.
The battery is there to crank the starter and provide a little help at low rpm and high electrical load.
It's correct position in the circuit is in parallel with the other loads. In this position the regulator has the best view of the state of charge and has a better chance of keeping it topped up provided the earth returns are not creating a difference in voltage between the battery negative and the regulator ground.

[mcquillr]

I see, because in my wiring diagram (in 1978 and earlier the regulator and rectifier were separate units) the regulator is connected directly to the third phase of the stator and has a ground but that's it. There aren't any other connections to the regulator. That third phase of the stator splits via a connector: one yellow wire to the regulator and one yellow wire as an input into the rectifier. This is where I am confused.

[Uncamitzi]

Actually, I think I was thinking about this wrong. The voltage off the stator is somewhere around 75V and once it leaves the rectifier circuit it should be around the proper range (13-14V) to charge the battery. If the battery is full, the regulator begins to draw power from the rectifier circuit straight to ground. If the rectifier can't dissipate the heat fast enough then that heat is passed off back to the stator (this is what can cause it to blow up).

Did I get it right this time?

looks right to me.. I can't see your diagram well enough to see how close it is to my 850g... but I'm sure some others will be able to tell you.

[mcquillr]

I can't see your diagram well enough to see how close it is to my 850g...

Shoot, is the image in the link not that big? That one was supposed to be a large version.

[mcquillr]

Most of my factory diagram appears to be similar to the one of BikeCliff's website:

https://onedrive.live.com/?cid=2370B62DDF9F0C6B&id=2370B62DDF9F0C6B%211033&parId=2370B62DDF9F0C6B%211030&o=OneUp

[Uncamitzi]

Shoot, is the image in the link not that big? That one was supposed to be a large version.

It's my age/sight and size of monitor more than the diagram.. I hear there's a procedure to eliminate the headlight loop.. and I'm going to get around to that.. but now that I have the series R/R my electrical seems to be doing MUCH better. (also cleaning the fuse box and all the connectors from stem to stern might have helped a bit too)

[Brendan W]

The charging system is capable of putting out more than the bike needs.
The wiring diagram shows how the bike deals with that.
The blue/white phase is connected directly to the rectifier. Consider it always on.
The green/white leg heads off to the lighting switch, returning as a red white. This leg is active when the light switch is on. Makes sense, more load more demand.
The yellow is connected to a regulator which modulates the output voltage, preventing it going too high. You may see values as high as 15 Volts or more in the service literature of the time.
Consensus here is to replace the separate regulator and rectifier with a series r/r unit like the SH775. Send all three phases directly to the new r/r input and dispense with the loop to the lighting switch altogether. In my case those two wires are just hanging there by the airbox doing nothing.
Those old units are notoriously unreliable and only looking for an excuse to fry your stator.

[mcquillr]

The charging system is capable of putting out more than the bike needs.
The wiring diagram shows how the bike deals with that.
The blue/white phase is connected directly to the rectifier. Consider it always on.
The green/white leg heads off to the lighting switch, returning as a red white. This leg is active when the light switch is on. Makes sense, more load more demand.
The yellow is connected to a regulator which modulates the output voltage, preventing it going too high. You may see values as high as 15 Volts or more in the service literature of the time.
Consensus here is to replace the separate regulator and rectifier with a series r/r unit like the SH775. Send all three phases directly to the new r/r input and dispense with the loop to the lighting switch altogether. In my case those two wires are just hanging there by the airbox doing nothing.
Those old units are notoriously unreliable and only looking for an excuse to fry your stator.

I agree this is a good plan! I have ordered the SH775. My bike doesn't actually have a headlight switch (US model I guess?). So I don't have to worry about closing that loop?

I'm just still unclear as to exactly how the regulator is modulating the output voltage. Everything you'll find explained on the internet is either a linear regulator or a zener diode regulator. Mine seems to involve a diode, thyrister and resistors?

[Brendan W]

I agree this is a good plan! I have ordered the SH775. My bike doesn't actually have a headlight switch (US model I guess?). So I don't have to worry about closing that loop?

I'm just still unclear as to exactly how the regulator is modulating the output voltage. Everything you'll find explained on the internet is either a linear regulator or a zener diode regulator. Mine seems to involve a diode, thyrister and resistors?

Getting rid of that loop also stops the thing melting itself and taking out other bits of harness with it.
My understanding of the old school shunt regulator is that it just dumps the output to ground effectively letting the stator winding deal with the current.
There have been a few discussions here along the lines that shunt regulation is akin to an electrical oil heater. There were thermal images of at least one bike showing marked lower casing temperatures after fitting a series r/r.
How exactly the shunt works is above my pay grade but at a guess the system voltage is controlling the gate of a diode and when it hits the set point it just dumps current to ground.
I recall Jim, Posplayr saying that shunt would have been the choice at the time as devices with fast enough switching frequency either weren't or couldn't be built. That is not true now although afaik the SH775 will come up short on some higher revving applications.
How do I remember this stuff. Sad really

[mcquillr]

Thank you Brendan!

Yesterday, I was able to replace the stator and the R/R. It looks like the bike is charging but I need to do a more though test. I'll try and do that later today after work.