You can't just use any hot wire. The only circuit killed with the bank angle is the starter system and the coils. The rest of the bike (lights, meters, etc.) remain hot.
The wire you want is BL/Wt. It's the one that comes from the kill switch to the coils and starter system. That's BLACK/WHITE shown below in the diagram of your kill/start switch system. Hooking to the Black/White wire from the kill switch to the coils will kill the coils and the fuel pump. All other wires remain hot. I would suggest that you use the BLACK/WHITE from the kill switch so the fuel pump will also be killed with the ignition both with the bank angle sensor and also the kill switch.
