G9 stopped running / won't run

[Todd Lipke]

160 plus compression
valve lash correct
good gas at carb
didn't seem to have spark, after replacing ignitor now does
can not seem to get anything other than occasional backfiring thru carb. Was a running cart used weekly, then ran sluggish and parked and never again would run.
I'have extensive automotive / drag race experience / builds and this dopey thing has me baffled. Help!

[slonomo]

It sounds like the problem is in the primary ignition system (Pulse coil, CDI). No way to know until you replace the parts. I suppose somewhere in the service manual you will find the specs on testing the resistance on those parts with a meter. Download the service manual, start there.

Also verify that the carb is genuine "Mikuni" and clean it well and spray the jets out. Check the throttle butterfly shaft for play. The Mikuni is 100 times better than any aftermarket "Mokini" china carb.

[CP241]

Hook a timing light up to the spark plug wire and watch the light flash. If you replaced the igniter with an aftermarket one I’ll bet dollars to donuts you’ll see that it’s either losing spark, or sparking erratically.