What the hell

[gsdapollo]

Ok, now im really dumbfounded. I installed a new solenoid, new battery. Bike started right up. Good to go. At the time I had the carb boots off as it had been 2 years since the bike has run so I was using a little started fluid to get her going. Once I got her running, I turned the bike off, removed the tank, disconnected the two plugs from the rectifier so I could move the airbox back a little to get the boots on. Reconnected the rectifier, put the tank back on, turned the key, pressed the starter, now nothing. I double checked the rectifier connectors and they are clean and connected properly, although that is the ignition circuit, not the starting circuit so it shouldnt have any effect on the bike not turning over as far as I can tell.

I pulled the solenoid off, bench tested it by applying power, looking for the "click" while testing for continuity between the two high amp terminals. Everything checked out fine. The solenoid clicked, and I got continuity between the terminals. Fuses are good too.

Put the solenoid back on, shorted the terminals with a screw driver to see if the starter died and the starter turned right over, so that checked out ok.

Now I started chasing volts. With the key turned on, im getting power to the entire bike. The Y/R wire that plugs into the solenoid is the wire that carries power from the starter button when pressed to the solenoid, which closes the solenoid and turns the starter. That wire should get no volts when the starter button is not pressed, and 12V when the button is PRESSED. Hooked up my multimeter, and it checked out perfectly.

Battery is also reading 12.6 volts

So, it appears everything is ok. Solenoid is getting power when starter button is pressed, but its not closing. Yet it closes just when bench tested. What the hell then? Any ideas?

Oh, its an 84 650 Nighthawk. I know its not a very common bike on here, but I would guess a starting circuit is pretty similar on most bikes and diagnosing electrical problems should be the same for any bike. Thanks!!

 

[Sonreir]

Check the ground side of the solenoid. You've checked for 12V going in, but have you checked for 12V coming out?

 

[gsdapollo]

Check the ground side of the solenoid. You've checked for 12V going in, but have you checked for 12V coming out?

Ya I am getting 12v coming out. To further elaborate on that. Power comes from battery, through 4 pin connector. Theres a higher gauge Red wire in that connector that carries power coming out of the solenoid from the battery to the ignition switch. Which ultimately goes to the fuse box and distributed to the rest of the bike, including the starter button. The Y/R wire mentioned previously, carries that power from the fuse box, through the starter button, and back to the solenoid. So the Red wire essentially powers the bike, which it does have power, and the Y/R wire carries it back to the solenoid to close it when the starter button is pressed.

 

[mydlyfkryzis]

If you have 12V in and 12V out of the solenoid, your ground side has a problem. Could be the main battery ground too...

Check the grounds The solid green wires are the system ground, follow them to a good chassis ground.

 

[roman_dog]

I'd agree that you have a ground problem. Have you made sure that the solenoid isn't being grounded out somewhere it shouldn't be?

 

[gsdapollo]

I found the problem, didnt have the gearbox switch plugged in, bike didnt know if it was in N or not. Damn thing has chillin on the swingarm completely out of sight. I guess she gets away with one this time... lol Thanks!!