ORIGINAL: JeffinTD
The ignition doesn't pull much for current. I'm sure 20ga servo wire would be fine. That is probably what the leads are on the switch/charge jack most people use anyway.
Before you install that engine of unknown history, I'd pull the top and bottom cover off the carb. There is a little filter screen you want to make sure is clean, and the little rubber flappers may have stuck.
Agreed. The last one I got the wires appeared to be even smaller than standard servo wires and it works with no issues. The wires never need to be larger than the switch wires.