Iknow the MCX is about as basic as you can get in Helis but Iam haveing control problems. Ichanged the original blades to the glow in the dark blades and now i am haveing stability issues. It seems very very twitchy. WhenIgo left, right revese and forward it seems ok but when Iadd tail swing it spirals down. Any ideas?
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First thing I would do is check the geometry on your Swash plate, linkage, and servo trim. Make sure the Swash plate sits level side to side and front to back with trims centered on your right stick. Correct linkage as needed, if way out of whack, start by removing the servo arms with the model turned off, then with the arms still off, power up your model, mark and unplug the motors if you want to play it safe. Then you can center your trims and slide the arms back on the servos. Any further adjustments there will be done with tie rod end links and trim. Test movement, it should be smooth with no stutter. Check for play EVERYWHERE. A little play isn't bad if everything is balanced, but blade shape could definitely affect things, specifically, make sure they are as true to each other as possible. Check all bearings, gear meshes, and look for any signs of wobble in the rotor heads, shafts, etc. If you have done all of that, and problems still persist, then you can fool around with your gyro settings. I have a used cx2 I just bought and actually had to drill a hole in the 3 in 1 motor controller in order to adjust a badly tuned factory setting... No info on any forum or online anywhere what that extra potentiometer is, but looks like some sort of balance adjustment between the motors. Took me two battery packs of just holding the model in my hands with varying degrees of throttle input to get the adjustments right... Anyway, this should get you pointed in the right direction, and definitely don't change more than one thing at a time, and pay attention to what each adjustment does. Good luck and hopefully you didn't get something messed up from factory- quality control sucks these days in china...