I have an 1981 cm400c, was driving it one day all was fine. The next time I went to start it, the bike refused to crank or turn over. The solenoid didn't click either. I baught. Aused solenoid and still nothing, so I baught a new one assuming the used was junk and still nothing. We are getting voltage down to the solenoid activation wires, the bike will start and run by jumping the solenoid posts, when I press the start button the headlight goes out, voltage goes to the solenoid but no crank. I was wondering if Im not getting enough amperage to the solenoid hat it's not activatibg? Thanks for any help!