Motorcycle Questions? Ask a Mechanic.
Hi and welcome to the site, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.
Initially, let's try and review the basics. Proposed preliminary checks (if have not been done):
Appreciate the information and on what has been tried.
Further with the basics / as a process of elimination. Proposed secondary checks (again if have not been done):
Sorry, mobile with sluggish Internet if at all.
Would run a sear for this connector soon as I get back to my regular workstation but may not be immediate.
Or perhaps you can post back with LINKs to pdf/electronic copies of both Service Manuals.
Incidentally, have you attempted to do a start with the side stand folded up?
Appreciate the links to the wiring diagrams and on your patience.
And yes, field/shop test would be by process of elimination. If all other factors checks good and yet no spark, then the Ignitor unit is deemed faulty if not highly suspect. The only sure way is to try and to (temporarily) replace with a known to be good Ignitor unit.
First, is there pulsating low voltage from the pickup coil when attempting to start? ...between the gray and black/blue wires?
Is there IGN+12V on the red/black wires to the ignition coils and the Ignitor unit?
How about on the red/blue wire to the Ignitor unit? ...on the blue/black wire?
The timing is dictated by the low pulsating voltage from the pickup coil. The pickup coil is fixed mounted. There are small/narrow metal tab(s) attached to the rotor that passes the face of the pickup coil. This action induces the low pulsating voltage. Since the stator/pickup coil is OEM and the rotor is presumably still the same, then the spark/timing could not have change / be off.
A bad ECU would be no spark at all.
On the otherhand, a low (or missing) IGN+12V on the red/black wires and/or on the red/blue wire to the Ignitor unit could cause weak/poor or no spark.
The "...left side ignition coil / red wire = 9.8 volts..." is concerning as I was expecting for it to be likewise 12V. Can you please re-check / trace this particular red wire?
Or better yet, temporarily hardwire both ignition coil's red wire terminal directly to the battery's + terminal for test purposes. Do not remove/disconnect the existing red wire.
I am tempted to suspect the ignition coil but it would be rare for both to fail at the same time hence the ignition coil with 9.8V reading on its red wire would be more suspect. Perhaps you can try the other way around, instead of hardwiring directly to the battery this particular ignition coil's red wire/terminal, temporarily disconnect; i,e, deliberately attempting to run the bike with just 1 cylinder/ignition coil.
Yes, you did mention donor ignition coils.
To my recollection, the gray wire from the ignitor unit would be for the front ignition coil.