More info would be helpful... However I think I know what you're looking for. I've flown a 4 Star 60 with an OS 61 FX for over a year, I keep a log book on my aircraft and I have 104 flights on her. She uses a flex cable otherwise know as a throttle cable. It connects to both ends with a connector that lets the cable pass through a hole and secured with a set screw. the connector itself pass through the servo arm and throttle horn and is secrured with a plastic snap ring. It has never caused me any problems, never came loose. I've seen this set up come loose on 1 other aircraft 1 time.
There is a draw back though if you shut down your aircraft with the throttle open you can't push it closed with your finger like you can using a push rod.
Just make sure that the plastic tube that the cable passes through is cut just so. If its too short the cable will flex and you won't get a good throw if its too long the tube will interfer with the throw itself.
Hope this helps Good Luck