From out of left feild (or at least the sail boat circles, model and full size), try Team McLube Sail Kote. http://www.888teammclube.com/frames/sailkote/index.html
It is a dry lubricant using PTFE (Dupont Krytox®), and is said to out last teflon type lubricants by many times. I have used it on my sailboat blocks (pulley's), fairleads, small motors, window tracks and yes, throttle cables on my aircraft. Spray it on and let it dryto an almost clear white powder that does not collect dirt. It comes in a 6 oz spray can, but is a little pricey ($8). Keep the throttle cables clean from oil and fuel and bends large and you should have no problems. Good Luck.