Topic: 1980 cb650c wont crank

[ToeCutter23]

 have an 80 cb650c that I’ve owned for 5 years. I parked it last winter and stupidly left it uncovered. T the beginning of the summer, I charged the battery and it tried to crank. Wouldn’t turn over but it tried. Left it alone for a few weeks and tried again. Nothing this time. I replaced the battery but now I can get nothing. The electronics work and I’m getting 12.44 volts at the battery. Just when I hit the starter button I get a “chunk” sound but the motor doesn’t turn. Replaced the starter and solenoid but still nothing. Any thoughts?

[DaveBarbier]

Can you turn it over with a wrench on the rotor bolt on the left side of the motor? Or rock it back and forth in gear? Could be stuck pistons.

All lights work? Battery to frame ground clean?

[harisuluv]

If the motor isn't turning, then battery, electronics, starter solenoid, all that is completely irrelevant. 

Most likely case is you now have a seized engine.  If not carefully prepped for storage this can and will readily happen.  Now if you want to verify that, you can disconnect the starter (not electrically) and then hit the starter.  If the starter spins, then you have verified that and the engine is stuck. 

After that you can do a search for unsticking an engine you will find dozens of posts/methods/threads.