BAD-BAD idea to remove the safety switch.
I actually took one apart, and you'd be surprised that it's not your average switch. The actual contacts are sealed inside a very small glass looking enclosure (I am guessing having a vacuum or having filled with one of inert gasses). And all of this is sealed with something looking like epoxy so nothing can even get close. The actuation of the swith occurs when the plunger is moved by the kickstand. The internal tip of the plunger has a magnet which interacts with magnet sensitive contacts inside that small glass enclosure, thus making them to close the circuit. As a result, the switch is very reliable. Any oil/humidity getting all over the switch won't degrade its operation.