Gs450 Ignition circuit trouble

[GsRocket]

1980 Gs450, Iv'e done my best to test the coils, which seem fine, and the CDI(not sure if i did it right but the circuit is complete still), and look around for any wires belonging to ignition that maybe be prone to shorting. I replaced my signal generator not to long ago and i tested that as well. Iv'e taken a look at Basscliffs tutorials and other websites but i'm not sure whats goin on. Side question: coils operate by opening and closing the ground and it alternates on each coil so you can only test one before you have to turn over the engine? either way both plugs gave spark today before it quit on me.

Now to the symptoms...

Bike was running fine before i took the front end apart to do a stem bearing replacement. when i put it back together it started up but died on me a few blocks away from home. Next day it also started up but died after a few minutes. Each time it dies there is no spark after even with a fresh battery. today i went out there and after my testing of components tested the plugs again and lo-behold bright blue arcs. Started it with some starter fluid and kept it running for a few minutes. put the tank back on and all the sudden no spark... and the weirdest part is the battery drained to 25% which i've never seen unless its defective.

So why is there no spark and it's draining a brand new battery??? i have 2 batteries both in good condition according to multimeter and my charger.


Update:
I'm thinking it might be my charging system since it will run with a fresh battery for a few minutes until the battery reaches 75%. I checked my stator wires and one of the connections burnt the plasic around it and the previously silver connection was bronzed. However when i tested all 3 wires the readings were fine 1.2 ohms each and infinint resistance against the case.

 

[tom203]

maybe the hot wire that runs from fusebox to ignition switch got abraded when you were monkeying with steering stem/handlebar and is sorta grounding out but not enough to trip main fuse but enough to drain battery.
Ignition coils build up a magnetic field which collapses when the igniter suddenly opens the connection to ground (triggered by signal coils)-this causes the spark. Some of these ignitors apparently don't like low voltage situations and won't fire.

 

[Guest]

I reckon Tom's probably onto something there.

I'm pretty sure when you head towards 10v and less you won't be getting a spark, so I'd ignore the ignition circuit as such to start with and look more at the connections and check for voltage loss in the harness.

With the battery full charged, what voltage are you getting at the orange/white wires that feed the coils?

I discovered on mine I was getting over a 2v loss to start with and most of that was due to dirty old contacts in the kill switch and ignition switch and a good clean with contact cleaner took that back to something like a 0.2v loss.

To check your charging system properly, you also need to get rev's up to 5K and make sure all three legs of your stator are putting out 75VAC, and with the R/R plugged in you should be getting somewhere in the vicinity of 14.8v also.

Read up on the stator papers to be sure...

 

[GsRocket]

I put new connections on my stator wires and clamped them down good and it seemed to do the trick. Not really sure when i bumped that since i was messin with the front end but oh well it works now

 

[Guest]

Excellent, glad to hear you got it sorted

 

[GsRocket]

So less than a week later i'm looking at the same problem, only worse. Now i don't get a spark even if the battery is fully charged. I saw a burnt connection from the rectifier to my lighting wire, my lights work however and i cut and recrimped the connection anyways, and what i assume is my ground(black wire) from the rectifier looks like its been severed(theres a broken connection wrapped in heatshrink tubing with a bit of soder in there.) I cant seem to locate the other end of this connection and will try again tomorrow but would this alone keep my bike from starting?? its seems like if these problems were affecting anything it would not get power to the lights or the starter motor either. I've spent some time staring at my wiring diagram but i'm still not positive on the order in which electricity reaches different components.
I'm not sure what i should look into next, last i checked my fuse is fine, stator is working(though it shouldnt affect starting) and there doesnt appear to be any other faulty wires.
All i need is for this 'ol girl to make it through christmas and she seems determined to spite me...

 

[Guest]

If the ground wire for the R/R really is cut and disconnected, you really want to get that connected back properly ASAP. If the R/R isn't grounding properly, the charging system is going to do all sorts of not nice things like over charging and undercharging, so you really want that to be fixed as a priority.

Having said that, if it's an aftermarket R/R with 6 wires and the green wire goes to ground, that means it's probably a Honda/Shindengen unit and that black wire could be the sense wire.

If that's the case, then it needs to go to switched 12v somewhere, not to ground. Having it disconnected is almost as bad as not having it grounded if that's the case...

Are there any model numbers on the R/R to identify it?

 

[tom203]

Gsrocket said....
"I saw a burnt connection from the rectifier to my lighting wire, my lights work however and i cut and recrimped the connection anyways, and what"

Does this mean you still have one stator wire going to headlight switch? If so, eliminate it . Original factory setup is trouble prone- wire ALL three stator wires direct to R/R to get better charging and eliminate the chance of the stator loop grounding out in wiring or in light switch.As Pete said, tell us what kind of R/R you got- take a pic if you can't read numbers.

 

[GsRocket]

Pete, its a 5wire(red, black, and 3 yellow) aftermarket unit from electrosport. I found a cut ground wire below my electrical panel and even though is black and white i think this was where it was severed. looking at the original RR it shows a B/W wire for ground.

Tom, If i were to cut the lighting wires out of my charging loop, one going to stator and the other going to rectifier, where would be a good point to re-insert these connections. It would have to be someplace that recieve a lot of voltage right?

I'm not sure if thats even neccessary though. My lights work which means my RR works?? My stator is tested fine. I seem to be getting electricity to everywhere but my plugs. The only thing i can think is a failing CDI or coils but i'm really hoping its just a loose connection someplace. I mean it was running this whole last week no problems then now it just wont spark.

 

[tom203]

The lights will work as long as you have battery (and until it dies)- the R/R just sends power into harness and it doesn't know where it goes! The headlight switch on 81 and earlier had one stator loop going thru it but it didn't power the headlight directly- it went up and back to R/R. The three stator wires need to go direct to R/R (those yellow wires). Follow wires from stator and you will find one that seperates itself from other two- this is the one that heads to switch and then returns to join the others and head to the R/R. The idea was to prevent overcharging IF you had headlight off. Review the charging tests (Basscliff's site) and make sure you are getting decent output- some of these ignitors are picky about low voltage.

 

[Normk]

This is directed to Tom203 but not limited.

Hoping that this is not heard as argumentative because your posts are always high quality. I am constantly trying to refine my understanding of all areas and to try to ensure that information presented is as accurate as it possible.


In a recent post, you referred to the stator output wire which passes through the headlight switch having the purpose of avoiding over charging when the headlight is off. Was this an inadvertent mis-statement?


The VRR's role is to prevent over charging and the fact that it is capable of doing so with the loop through the headlight switch bypassed indicates that it is capable of doing so. The intended purpose would seem to be to reduce AC output, obviously, but the effect would not be to reduce DC output/charging, because the VRR does this in both connection scenarios.


I believe the disadvantage, as I think you pointed out in another thread, is that the stator load is unbalanced when this output is open which may be detrimental to stator life. The disadvantage of by-passing would seem to be additional VR load which may or may not affect the life of the original VRR. Is one runs with headlight on at all times, the difference is moot excepting to dispense with one problem area.

Is anyone aware of conclusive evidence in either direction?

After much consideration I entered the "bypass the headlight switch loop" camp but still actively working to understand these systems to a higher degree. Begging the indulgence of others in this regards.

 

[tom203]

I was trying to simplify what the headlight switched stator loop was doing - without too many details. Actually, opencircuiting one phase of a 3 phase alternator drops its output considerably making it run cooler which is good for stator (as less current is circulating in it ), but this means not as much power makes it to R/R, so its output might be too low- after all, the R/R can dump excess to ground, but it can't boost it. Note that at idle, there is very little surplus power available. My bike with Shindengen R/R only puts out about 12.7 volts at idle (lights on)- by 2000 rpm ,it hits 14 volts. Follow the links to the Compufire R/R for a different approach to charging .

 

[Guest]

Pete, its a 5wire(red, black, and 3 yellow) aftermarket unit from electrosport. I found a cut ground wire below my electrical panel and even though is black and white i think this was where it was severed. looking at the original RR it shows a B/W wire for ground.

Tom, If i were to cut the lighting wires out of my charging loop, one going to stator and the other going to rectifier, where would be a good point to re-insert these connections. It would have to be someplace that recieve a lot of voltage right?

I'm not sure if thats even neccessary though. My lights work which means my RR works?? My stator is tested fine. I seem to be getting electricity to everywhere but my plugs. The only thing i can think is a failing CDI or coils but i'm really hoping its just a loose connection someplace. I mean it was running this whole last week no problems then now it just wont spark.

If it's a five wire, then yes the black or black with white tracer will be ground. The stock ground wires on my '82 are all black/white.

To do the headlight/stator modification, you should be able to just unplug the bullet connectors to bypass the circuit.

On mine, it was either a white with red tracer or white with green tracer (can't remember off the top of my head) that made the loop up through the headlight switch. Mine was bypassed by a PO but it should be the same deal. Just unplug the one stator lead which goes to the loop and plug it in where the loop returns to the harness. I hope that makes sense... I'm not sure if you'll need to replace a bullet connector to make it work as mine was already done.

 

[BassCliff]

Hi,

In a recent post, you referred to the stator output wire which passes through the headlight switch having the purpose of avoiding over charging when the headlight is off. Was this an inadvertent mis-statement?

My GS850 doesn't even have a headlight switch. Yet, because Suzuki likes to empty its parts bins before manufacturing a new part, one leg of the stator was connected to the loop of wire that runs up to the non-existent switch. I disconnected this useless loop of wire and connected all three stator legs directly to the r/r inputs. It's documented here: Regulator/Rectifier Replacement

This has been common practice for quite a while among members. You can read about it here: http://www.thegsresources.com/garage/gs_statorfacts.htm

On these old wiring harnesses, any chance to eliminate points of failure is a good thing.



Thank you for your indulgence,

BassCliff

 

[Normk]

The question revolved around the application of the term "charging" which Tom203 has explained as simply short hand. Make sense as thought it must be something like that but did not wish to see someone mislead. I have always felt that it hurts nothing to repeat or to clarify so long as one is polite. No one takes the time to proof and re-read posts to the degree required to meet all challenges to semantics and terminology.

FWIW, some of these bikes have the headlight On-Off switch blocked so that it cannot be moved into the Off position. This is accomplished by a blade cast into the bottom of the plastic switch knob which prevents the switch from moving. Remove the knob screw, slide knob off switch arm, trim blade from bottom of knob, reassemble, and the headlight can be switched off.

I use this provision in order to avoid battery discharge when sitting in traffic & using grip heaters. It is also useful when starting to avoid cycling the HID headlight as they are reported to resent this treatment.

At some point it may seem worth while to encorporate some additonal strategy to reduce cycling of the HID such as a delay timer tied to oil pressure, etc. Right now it seems sufficient to simply switch off headlight before turning on ignition switch and starting. When engine is stable, on goes the light and off we go!

Hi,



My GS850 doesn't even have a headlight switch. Yet, because Suzuki likes to empty its parts bins before manufacturing a new part, one leg of the stator was connected to the loop of wire that runs up to the non-existent switch. I disconnected this useless loop of wire and connected all three stator legs directly to the r/r inputs. It's documented here: Regulator/Rectifier Replacement

This has been common practice for quite a while among members. You can read about it here: http://www.thegsresources.com/garage/gs_statorfacts.htm

On these old wiring harnesses, any chance to eliminate points of failure is a good thing.



Thank you for your indulgence,

BassCliff

 

[GsRocket]

All,
This has brought up a very interesting discussion and i will consider switching the wires after it is running fine again so i can see the difference in voltage. In the meantime its not a charging issue, i'm still working on getting spark. I guess i mistook the RR to affect spark when really its only charging. Am i correct to assume that the only reasons for it not to spark would be connections, my signal generator, CDI ignition box, and the coils? I'm not sure how to check the CDI or the signal generator. Because of the timing i noticed the broken ground it probably fried something, just not sure what.
Thanks for all the input so far.

 

[tom203]

Your electrical system needs to deliver a decent voltage ( maybe > 11 volts) to ignitor in order to get things to fire happily. Having 13 volts at battery doesn't mean the ignitor sees this, as connection losses take their toll. Engaging the starter makes things worst. The power goes from battery to fusebox on to igntion switch and on to kill switch and then heads to coils and ignitor. Double check these places and measure voltage at ignitor . Basscliff's site has some good ideas on testing ignition components.

 

[Guest]

Your electrical system needs to deliver a decent voltage ( maybe > 11 volts) to ignitor in order to get things to fire happily. Having 13 volts at battery doesn't mean the ignitor sees this, as connection losses take their toll. Engaging the starter makes things worst. The power goes from battery to fusebox on to igntion switch and on to kill switch and then heads to coils and ignitor. Double check these places and measure voltage at ignitor . Basscliff's site has some good ideas on testing ignition components.

Yep, +1, this is why I was saying to eliminate any voltage loss first.

There will be a point at which too much voltage drop causes things to stop working. I'm not sure what this point is, but if you end up with 9v at the ignitor for example, this may be too low for it to drive the coils. Same with the coils, there is a point where the spark will become too weak to fire anything...

Also, if you do various tests while there's not enough voltage, it may even make you think components are faulty when they're not.

The ground wire directly on the R/R may not impact too much aside from the R/R but I'd still take care of it first with the rest of the connections.

As for testing the ignitor (it's not a CDI ) and signal generator, the Clymer manual has tests for these which can be downloaded from BassCliff's site.