Bike issues

[The Buddha]

CDI on a GS usually never dies. but I anyway I think your problem could be solved now.
Signal generator says when to spark and the ignitor sends the voltage to the coil to spark, and each coil sparks for the cylinder. The ignition rotor says which cylinder needs the spark.
Cool.
Buddha.

[Jimbob]

Yeah hopefully that's fixed it. My next thing it look is why it's about 13.5 volts at 1.5k rpm but goes down when the revs go higher

[mr72]

Yeah hopefully that's fixed it. My next thing it look is why it's about 13.5 volts at 1.5k rpm but goes down when the revs go higher

It's probably because of corrosion or melted plugs in between the alternator and the regulator/rectifier.

It will never charge correctly at 13.5V or below. You need to be making >13.8V at the battery terminals to consistently charge the battery.

BTW the CDI is the ignition module. It's what actually fires the coils. You could also have one or more bad coils in addition to the charging and battery issues. Ignition issues are not necessarily (or often) directly related to the charging issues you have.

With any luck your problem with the bike dying when hot was the signal generator (pick up coils) and not something worse.