Originally Posted by studawg66

Been lurking and searching and can't quite get the answer, so here goes:
I have a hand-me-down mCX2 that the guy said had a gear mesh issue. Got it really cheap. Turns out the gears mesh perfectly fine and motors seem to be in the right position, but the clockwise motor (for the bottom blades) starts off trying to spin then shuts down, meaning the motor stops turning and now both sets of blades start spinning in the same direction. I checked over and over and the gears are still meshed during this whole process, so the way I look at it I have one of two problems:
1. Bad CW motor - have some spare parts on order and will try to swap it out soon
2. Could it be that the friction between the inner and outer shafts is too great? If you try to spin both sets of blades in their proper directions using your fingers, how much resistance do you get? I get more than "free wheel" resistance, but it is not totally binding up. Should these things move basically friction free? If so, I either need some lube or a replacement shaft or bearing or something. Ideas?

Thanks,
Stuart

It should spin fairly freely, but you will feel a little resistance. If you spin the blade you should be able to get a few rotations out of it before it stops.

Following along with what Chap said, did you rebind this transmitter to the helicopter? Try what chap said and see if that helps. You could also try rebinding it if it already came bound to the transmitter.
If those fail, it does sound like it could be a bad motor. I have had 2 burn up on me in 1 1/2 months time. Just luck of the draw on these little can motors. Also make sure the motor has not slipped and causing the pinion to hit both gears. In a hard crash, the stuff they use to hold the motors in, can break and cause the motor to slip.

Originally Posted by Chap1012

Hi Stu, I assume you have the stock TX. Try bringing the trim on the throttle all the way up then all the way down. Then center it. Do this with the heli off. Then, try it with the heli on.

Mike.

Thanks, Mike. I will try that. By the way, I do have the stock TX but I also have a DX7. Would binding it to my DX7 have any effect on this? I'll have to give that a shot as well. I didn't even think about a potential Tx issue.
Like I said, it seems as if the motor starts turning (awful vibration) then just shuts down completely. The CCW motor has no issues and runs fine.

I'll let you know what I find out. Thanks again!

Originally Posted by studawg66

Thanks, Mike. I will try that. By the way, I do have the stock TX but I also have a DX7. Would binding it to my DX7 have any effect on this? I'll have to give that a shot as well. I didn't even think about a potential Tx issue.
Like I said, it seems as if the motor starts turning (awful vibration) then just shuts down completely. The CCW motor has no issues and runs fine.

I'll let you know what I find out. Thanks again!

I would have to agree with DD. If the motor is hot (or even warm) on a short spin up and vibrating, I would say it is shot. IMMHO and also my experience, it's always best to replace the two motors on a coax. Mark the bad one, keep'em together. Throw "NOTHING" away Welcome to the world of having a "parts bin."

Mike.

check out my new mCX2 mods!!!!

https://www.rcgroups.com/forums/show...3#post19537796

VERY nice!!!!!!!!

I am performing an experiment to see if I can liven mine up a bit. Pulled off the flybar weights, cut the flybar down by .25 inch, glued weights back on with some clear RTV. Waiting for it to dry, then test fly it in the garage.

After all, one of the "peformance" mods for the bigger coaxs is a shorter flybar, or lighter weights.

Oh yeah, just for the fun of it, I tried flying it one time without the weights. Fuggetaboutitclyde! :-0

[QUOTE=valiantGLX;19537814]check out my new mCX2 mods!!!!
/[QUOTE]
Is that the stock distance between upper and lower rotors?
Club Heli has a new brushless kit for an Mcpx that is $66. It includes one brushless main motor. I guess you'd have to double that kit for a coax = $$$$$$$$$

Originally Posted by kodak_jack

Is that the stock distance between upper and lower rotors?
Club Heli has a new brushless kit for an Mcpx that is $66. It includes one brushless main motor. I guess you'd have to double that kit for a coax = $$$$$$$$$

Yep its the stock outer shaft, so stock distance. The outer shaft, 5-in-1 board, blades and the motors are the only stock parts left on it though.

Brushless is over-rated, the stock motors do the job quite well, and have herculean strength if you treat them well. I have had close to 200 flights now without any issues, and my flying is pretty extreme at times.

vvvvv This is how stable my mCX2 is after my mods vvvvv

MCX2 flying with no stick input.avi (4 min 22 sec)

Originally Posted by cbxer55

I am performing an experiment to see if I can liven mine up a bit. Pulled off the flybar weights, cut the flybar down by .25 inch, glued weights back on with some clear RTV. Waiting for it to dry, then test fly it in the garage.

After all, one of the "peformance" mods for the bigger coaxs is a shorter flybar, or lighter weights.

Oh yeah, just for the fun of it, I tried flying it one time without the weights. Fuggetaboutitclyde! :-0

I have just reduced the weight and length of my stabiliser flybar. It was probably the quickest and easiest of all my mods.

See the following link, for pictorial instructions:

https://www.rcgroups.com/forums/show...3#post19543366

Mine flew quite well with the .25 shortened flybar. But the stock weights, which I refastened with silicone adhesive, did not stay on well. Had a mild crash, no damage, when one of the weights departed while hovering. Flopped over on its side so fast!!!!

Gonna go to the lhs today and pick up some small wheel collars. Probably shorten the flybar another .25, so it will be one inch long from the edge of the pivot frame to the end of the flybar.

Another thing which improves the performance is to tighten the screw at the top of the mast. Tighten it as far as it will go without restricting the flybar movement. This eliminates the ability of the flybar to wiggle-wobble back-and-forth in the horizontal plane.

Mine was flying last night fff with no death wobble on left turns. I was flying full left 360s about 10 foot diameter, with a forward cg, and just a very mild wiggle, no falling out of the sky.

Does the aluminum frame do anything to hold the motors better so they don't slip?

Originally Posted by kodak_jack

Does the aluminum frame do anything to hold the motors better so they don't slip?

Go to Ace hardware and get a tube of clear LEXEL. Just a little dab on the frame/motor will do it BTW, no "real" work shop should be without a tube of this stuff...trust me.

Mike.

I rubbed a bit of clear silicone across the entire motor/frame interface, motors stay in place on the hardest LVC landings.

Originally Posted by kodak_jack

Does the aluminum frame do anything to hold the motors better so they don't slip?

The Aluminium main frame has holding screws for the motors, and they have never moved, with no glue or anything