Boxerworks.com

Hey folks, 1st time post. I ride a 75 r60/6. I've only owned it for 2 months. I've put 500 miles on it riding to and from work. Up until yesterday things were going great. Yesterday morning it didn't start. No crank, no click, no sound, nothing. I took the battery out and charged it up, it was actually fine. I noticed that the ground wire from the battery to the engine looked old and corroded, replaced it. Still nothing.
Today I did some digging around in the bike. I was thinking it could be these things.
1 dead battery
2 bad ground
3 bad starter
4 bad starter relay
5 bad wires from start button
I took the starter out and tested it. Works fine
I took the starter relay off the bike and cleaned all the connections
I took the right side handle switches off and checked continuity to the board in the headlight
Everything checked out fine but still no crank.
Would someone confirm I'm on the right track for finding the problem please? My next thought was to plug a wire from the starter relay to the starter solenoid blade and bypass wherever the original wire travels to from the relay to solenoid. I could also buy a new starter relay but I'm not sure I need one.... I'm not sure how to test it.
The bike has 66000 miles, everything is original and was in perfect working order until yesterday. All lights, and electrics worked well.
Thanks for your help.

I'm assuming everything works except the starter, right?
Run a jumper wire from the battery positive to the starter solenoid and see if the bike starts.
That would indicate no major issues.

With 50 year old machines every relay, wire, connector and switch is a suspect until proven innocent.
The nice thing about these bikes is that everything can be trouble-shot with a simple test light and/or a multimeter.
If you're handy with a test light and can follow a wiring schematic it shouldn't take long to figure out.