1982 Gs 1100 Igniter questions

[simonk]

Hello folks, hope someone here can help, I have lost all spark on my bike, oddly it fired up beautifully warmed up, sat ticking nicely, so I turned it off ….left it five minutes and now nothing. So here is what I have done. New plugs, new coils, second hand but are reading within specs on primary and secondary, I’ve checked the pick up coils and they too are within specs, I have replaced the ignitor, checked earths and leads, I checked the plug caps, they were reading 9k so put some new 5k caps on, I have 12 volts at the coils, on the orange and white wire, I should say that the system is non mechanical advance, and an 8 wire ignitor, so here is my first question I also have power down both the white and black/yellow wires coming from the coils, when the ignition is on…is that normal ? Question two…should the ignitor casing be earthed to the bike as well as the black and white wire coming from it? I don’t know what else to check as all other electrics are fine, lights,horn, kill switch etc.
The valve shims have been done and the carbs rebuilt. It is definitely a spark issue, or lack of spark ! So what causes total failure of the ignition system ? Any help appreciated thanks.

 

[Rijko]

the igniter could be the issue, they are not extremely reliable.

Throwing parts at a problem complicates things ... you have introduced
new variables to a troubleshooting situation, making it harder.

Is this the 8-valve GS1100, or the 16-valve aka GSX1100 ?

 

[pdqford]

so here is my first question I also have power down both the white and black/yellow wires coming from the coils, when the ignition is on…is that normal ?

When the ignitor pulls the coil to ground to charge up the coil primary you would only see a few volts on the coil wire going to the ignitor.
(The coil would consume most of the available voltage.)

When the ignitor release the coil ground to discharge the coil you would see near battery voltage on the coil wire going to the ignitor.
(The coil is turned off so you would see open circuit voltage since no current is flowing through the circuit.)

Question two…should the ignitor casing be earthed to the bike as well as the black and white wire coming from it?

The ignitor casing does not need to be grounded as the B/W wire provides the ground for the ignitor electronics (as well as the path to ground for the coil primary when the ignitor grounds the coil).​

 

[Nessism]

A failed R/R can cause high charging voltage, and that can take out the ignitor.

 

[simonk]

Thank you all for your sage comments, I know just chopping bits in and out is not the solution. There was method working back from the plugs, then caps then leads, coils etc. I have her running now and s voltage check across the battery is giving me 18 volts, so I swapped out the reg rec and I still have 18 volts, so I have checked the ohms and continuity to earth (or lack of) on the stator, and they were within spec, I will try another reg rec, if you any ideas i would appreciate it.thank you.

 

[Grimly]

Do not run it any more with 18Volts! You're right on the teetering edge of destroying your ignitor, and I'm surprised it's survived thus far.
You need the Miracle of a Series reg-rec, the Holy Grail of an SH-775.

 

[Rich82GS750TZ]

This is not the way:
" 18 volts, so I swapped out the reg rec and I still have 18 volts, so I have checked the ohms and continuity to earth (or lack of) on the stator, and they were within spec, I will try another reg rec,"

This is the way:
"Do not run it any more with 18Volts! You're right on the teetering edge of destroying your ignitor, and I'm surprised it's survived thus far.
You need the Miracle of a Series reg-rec, the Holy Grail of an SH-775."

​

 

[simonk]

understood thank you

 

[Rich82GS750TZ]

There's been enough written on this site about using a genuine Shindengen SH-775 R/R as a replacement for stock that's it's hardly worth thinking about doing anything else. Yes, you can read the stator papers, and pour through thread after thread about shunt vs. series and mosfet vs. blah-blah-blah. The write-up linked in my signature re: my charging system is pretty thorough, and fairly typical, if you want something to read.