PJ, I'll defer to Jim for the diag of anything SOHC ignition, he's the expert on them.
There is a test procedure in the FSM for the CDI's using one of 2 analog VOM's, different spec's depending on which meter you use. From the FSMThere should be a test procedure in service manual?
CDI is Capacitor Discharge Ignition.
Capacitance testers are uncommon but are available. The diode tests for 'black box' were always relevant when I was working at dealers. The only real difficulty, your not using the exact same meter Honda used in 1978 so expect the numbers to be within 20% of factory spec. I would test generator low speed coil as it was a known failure point, bike would start and run but when turned off would not re-start as low speed charging coil had broken down. As it's a simple continuity test it won't take long (remove left side cover and test at generator plug) It may be worthwhile removing sprocket cover just to make sure wiring didn't get trapped or cut through by drive chain?
Electrical stuff can be tricky. What id do is follow Jim’s detailed instructions and go through it slowly. He made a thread that says what to test and what the spec should be. I think I might make a you tube video about this topic. Worth a shot I’m always one for trying new things. Ps it took me a few times of going bsck and trying to test again before I understood what I was doing and testingWell I m lost confused and fed up... 🥺
New coil reads 5 ohms and old reads 0.8 ohms. Now my cdi may be dead.