Hello, CBRF. I am new here; I haven't frequented any forums in decades. What a beautiful place you have here =^)

So,
My current old i4 Honda has me thrown for a loop. I do not know where else to turn. The bike in question is a 2006 CB600f, otherwise known as the Hornet or "599". A few years back, I found a melted R/R on my '92 F2 CBR and dove into how we diagnose issues with the charging system on these bikes.

Around 2 months ago, I found a crispy connection at the R/R on the 599. So, we have 0.5ohms between my 3 yellow stator wires, no shorts to ground, and sufficient AC output: awesome! The stator is reliable. The rectifier plug didn't make it, so I replaced the rectifier and soldered my new connections. As I understand, my 3 stator wires are interchangeable. The diagram for the new RR states that two of them are "charge" wires and one is a "signal".

The good:
I have sufficient charging voltage; up to 14.5V around 5k RPM. In fact, the bike runs and charges beautifully now.

The very ugly:
The starter motor is intermittently refusing to stop. Sometimes, I can start and run the bike, kill it and it goes to right sleep. Other times, the starter motor will not quit until the battery is disconnected. I believe the starter switch is not the culprit, as the connections look clean and the headlight resumes after the switch is released and the bike is running. I am not entirely certain on how to rule out the solenoid as part of the issue.. I know the starter is not just sticking to the flywheel because it is obviously pulling current when it isn't supposed to. I cannot find any connections that may have melted to a short. Perhaps this is above my pay grade, but I would greatly appreciate some advice on further troubleshooting.
The first sign of trouble
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To test solenoid, unplug red solenoid connector when starter won't stop. If starter continues running, then starter-solenoid contacts are sticky on inside.

 

Bingo. Thank you for your response. I will order a new relay/solenoid and report back.

 

Test existing solenoid to verify it's sticking.

I've also had this issue with start-button that was sticking as well.

 

the old relay was sticking. I should've checked that with the meter to begin with. $10 ebay solenoid has everything back the way it should be. Thank you for the advice!!