Here's a generic example of driving a motor by button.
The xBox right/left triggers though are actually treated as axis 2 & 3, so you'd need a variation.
The Left and right triggers produce a floating point number from 0.0-1.0
So give yourself a little wiggle space and replace the button feeds in the example with the checks:
Axis 2 > .1 (or .5)
Axis 3 > .1
So something like this:
