Having a servo within 10" of the spark plug or ignition coil is a bad idea. The windings from the servo pick up the pulse and transmit it directly to the receiver. EMI very possible. Use a plastic Sullivan rod or similar to operate the throttle andkeep theservos for throttle andchoke/smoke behind the fuel tank.The straight light-blue tubes in these images are Sullivan Gold-n-rods to servos 12" from the magneto of this model.