Here's a walkthrough of how the starter relay circuit goes. You should be able to narrow down which part is bad just by seeing where you do and don't have 12V.
- White wire carries power from the Main fuse up to the keyswitch.
- When turned on, power goes out the brown wire to the fusebox.
- Then through the Ignition fuse and out the brown/black.
- That goes into the kill switch.
- Power goes out on the red wire and back into the starter button.
- Then out on the black/red and into Diode B.
- Out on the blue wire and into the starter circuit relay.
- Yellow/red is power out of the relay into the solenoid.
You should be able to check for 12V between any of those points and ground, to figure out where the breakdown in the circuit is.
If the bike starts and runs when jumpering the solenoid, you know that the parts necessary for the bike to run are working. The red wire out of the kill switch also feeds the coils, so you know everything works up to #5.
At this point, it has to be the starter button, diode B, the starter circuit relay, or the wiring between those. If you have power on black/red when pushing the starter button, the button is good. If you also have power on blue, you know the diode is also good.
The starter circuit relay's coil grounds through the safety switches. If those aren't working properly, then the relay won't operate when the blue wire is powered. When it's "safe" the yellow/green wire at the relay should be grounded. If you're not getting ground there in neutral or with the sidestand up and the clutch pulled, you have a problem with the safety switches/circuits.