Lost key to polan 5hp riding mower can someone tel me witch wires to cut to make it run on a switch thanks.

I would think so. Look for the wire form the battery to the switch. Now trace the wire from the solenoid to the switch. That is the wire that kicks the starter. Now the 3rd wire here to keep it running is the key.

If you look at the switch back and see the order the wires are in that would be the ticket here. As you turn the ignition switch to "on" and then to "start" the switch springs back yo the running position. Inside the switch are a couple of contacts that rotate to the next position from the Run to the Starter to complete the connection. The missing wire is the Run wire and that can be traced off the back switch. It will more then likely have other wires to that Post in the switch for safety switch's in the system and the lights.

So there are the basics here