I have a 1973 superglide power to headlight
Push the handlebar button nothing happens.
Screwdriver across the 2 big bolts on the starter relay engine turns over. Is the relay bad?

 

Could be one of several things, the button's bad, wiring break somewhere, relay or a circuit breaker gave it up. You need to do a little more troubleshooting narrow it down a bit.

 

I need to diagnose my non-functioning starter as well, hope no one minds if I tag onto this thread. To determine whether the solenoid is the issue, short across the two big posts? Does key need to be on? Neophyte here... ;-)

 

I have replaced that stupid little start button quite a few times. I have power at the button. Ill check the breakers. I've had the bike almost 20 years never replaced those. Thank you

 

If you go from the top big terminal to the little terminal with the key on...the bike should crank...that will tell you if the solinoid is working.


Going from one big terminal to the other one just spins the starter without pushing out the bendix.

 

 

Now that is clever...

 

Ran a wire from the small terminal to the large and got nothing but sparks. Ran wire across the two large terminals and got nothing but sparks. Time for a starter/solenoid swap it appears.