Induction Motor Wire Size
You can't find this in a wire's datasheet since it almost entirely depends on the application. For example, any wire can take as much current as you want as long as the pulse is short enough.
You need to calculate this yourself: Choose a wire diameter that can handle your continuous current (there are tables for that), then figure out what happens during the turn-on current spike. To do this, you have to calculate the total energy dissipated in the wire (you can estimate this as E=I²Rt, where I is the peak current, R is the resistance of the wire and t the duration of the pulse). Then you divide the energy by the thermal capacity of your wire and you get the temperature delta of the wire after the pulse (deltaT=E/(Sm), where S is the specific heat of copper and m is the total mass of copper in your wire). Based on the heating of the wire, you can then determine whether the choosen wire diameter is okay or whether you should make the wire bigger.
Given that the current spike is generated by a capacitor, you can also estimate the energy to be dissipated in the wire as being equal to the energy that has to be pushed into the capacitor to charge it up.