I use bicycle brake cables for throttle cables all the time. You can buy brass fittings at any local hardware store that are designed for 1/8" tubing (plastic, steel, copper, etc), the kind that come with a ferrule. If you take a utility knife and cut the plastic housing off of the brake cable (1/2" from the end, roughly) you will see a steel core underneath it. This steel core fits in the ferrule perfectly, it can be tightened down pretty snug without crushing the cable and holds well. If needed, I can post pictures for you. Also, the above mentioned brake cable adjuster is a great idea too! It makes adjustments quick and easy if the throttle cable ever stretches.