2001 Polaris SPortsman 400 was running like poop so I did some digging and relaize its in the switch. the question is this.

Black wire on rev box when disconnected solves the issue! great! but why does this wire effect shutting of the machine?

I turn the key with black wire disconnected it does not shut off.

IS this as simple as throwing in a switch from that wire to what it plugged into (looks like three black wires into on connector).