i like to braid the wires out of the motor for the first couple of inches then put some heat shrink on to hold the braid in place. the wires seem to roll around corners better, especially where they're coming out the motors and then making a 180 degree turn into the tubes. a few twists in the arms is enough to keep interference down. the methods above keep the wires close to each other which reduces interference. twists, braids, nylon sheathing, etc. all accomplish the same thing basically.
bart