My GS550E is stalling unpredictably.

[Ira]

What is the voltage at the coils?

Have you had a chance to go through the electrical? You should have less than 1V drop at the coils compared to your battery voltage.

How are your plug caps and leads? What resistance readings do you get across them?

The wiring is all new, so there's not much if any drop between the battery and coil. The leads are old(stock) and the caps are new. I don't recall what resistance read, but it was uniform across all 4.

[eil]

If you haven't touched the carbs lately, running rich can also indicate an air restriction. Check the air filter? Something make a nest in the airbox or exhaust?

Could still be electrical too, I have read of others having intermittent problems with their coils and ignitor.