As it so happens I just had to replace both coils at 480 hours. Yes they do fail and it not ucommon for them to fail . The post below explains why. The transistor managed coils are not all that robust given the hostile environment they live in ,primarily heat related.
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FD731V and other Kawasaki twin cylinders
This is not a plea for help as it has been fixed, just a heads up on cause and effect. The ignition coils on these engines are different from the #1 and #2 side with different part numbers and have a pair of transistors inside the units that control primary winding charging and field collapse...
