Do simplest and easiest tests first:
1. Key ON, do you have +12v going to each red-wire terminal on each coil? Use battery negative or chassis ground for negative multimeter probe.
2. Key ON, measure actual voltage on grey wire going into ignitor connector. Volts = ???
3. Easy test for coil-triggering signals is connect
'noid light to coil primary wires (use test-leads with alligator clips). It will flash when there's grounding pulses to dump coil (requires passing test#1).
4. only if #3 fails test (no blinking) then you'll want more in-depth analysis of crank trigger signal with oscilloscope. Never heard of one failing on this model bike though.
Implicit in these functional measurements is also testing wiring between individual components. Most of time, parts are perfectly fine, but it's wiring in between that's bad. This is due to using low-spec unsealed connectors with uncoated bare-brass terminals. Corrosion sets in over time and causes problems.