1983 Yamaha XJ750R Seca Won’t Start

Hey everyone!
So I’m a long time lurker, first time poster...
Anyways, I picked up a ‘83 750 Seca back a month and a half ago and had no problems with it up until now.

So the bike won’t start after I came home from riding it last night, and I’m not 100% sure why.
Im fairly sure that it’s because the solenoid is cooked, but I’d like some opinions and advice before I rule it that indefinitely.

When I jump the solenoid I can hear the starting motor working, but the bike never fires up.
I pulled the spark plug and held it to the frame and it doesn’t look like I’m getting any spark while I jump the solenoid either.
Does the solenoid interact with the coil pack telling it to go?
It says my bike takes part number: 4KD-81940-00-00 as the solenoid, but can I use other ones as a replacement?
Are both of these redundant and the problem lies within the coil pack?
Could the starter switch on the handlebar be broken too?

I know that’s a lot of questions but I’m not quite sure what to narrow it down to.

Any advice is greatly appreciated!
Thanks.

 

Question how old is your battery, and if it is a lead acid battery is it serviced to proper level with distilled water? A low battery might crank but below 10 volts TCI will not allow spark , it is not a lot of difference . Solenoids are cheap, I had to replace mine as original would stop working occasionally. I bought 2 so I have a spare. I would replace this first and look at battery and grounds.

 

You could also jump lead it from your truck.......I have done this loads of times, see if it turns over, if it does, problem is your battery

 

Starting with the battery is good advice. Measure the battery with no load, it should be close to 12.8 volts and not drop below 10 volts when the starter is engaged.

And for some of your other questions:

Jumping the starter at the solenoid does apply power to the starter, but only there. If the key is set to "ON" the bike should have spark and fire up if the solenoid engaging was the only issue. Of course, make sure you are in neutral before jumping the solenoid.

Not directly, but they do share 12V ignition - see below for fuse box.

There are a number of reasons the starter may not spin when the start button is pushed, and yes the starter button can be at fault. It's a process of elimination through some troubleshooting checks. This thread covers the 650, but it gives some really good tips on how to troubleshoot starter problems.

https://www.xjbikes.com/forums/threads/how-to-test-your-starter-circuit.7828/

Also, if you have not addressed it the fuse box can be the issue if the 12V ignition is missing:

https://www.xjbikes.com/forums/threads/your-fuse-box-a-ticking-bomb-by-rick-massey.2210/

https://www.xjbikes.com/forums/threads/how-to-install-an-aftermarket-fuse-box.6350/