This 1980 Suzuki SP400 project has been dragging me through the mud for more than a year. After cleaning up some frame grounds I got it to start, but it has been horribly unreliable since then fading in and out of functionality until finally dying altogether.
At this point I have replaced everything in the ignition system with spares from ebay including: 4 Stators
2 Ignition Coils
1 Wiring Harness
1 Plug Boot
1 Spark Plug
When I first got the project I got the spark back by cleaning up some frame grounds, but then it would frequently die once hot and/or die in the rain. I started changing stators and it would run for a while. But now it seems to be permanently dead. Readings from the newest stator are within optimal range according to the Suzuki manual, although the pickup voltage seems to be reading under half a volt.
Still no spark though! I've tried every combination of every CDI and Stator. Nothing! No spark with the boot pulled off either. Kill switch has been totally disconnected.
This bike can actually be run without a key if you disconnect the blade plug from the ignition coil, which i have done. The ignition system has been completely isolated. Still nothing! It's a very simple ignition system. Stator > CDI > Plug > Spark.
Check out the ignition and wiring diagram for more details.
Anyone have experience with ghostly old ignitions on these SPs or GNs or DRs? If it's not something complicated, maybe it's something simple??