mCPX turns CW 45 degrees every 3 or 4 secs

[CaptHal8HS]

So I have this problem with BOTH of my mCPX's. If I bring the bird in to a hover, she just sits there nice. But when I start to fly, the tail kicks CW 45 degrees. There are times when it will just keep kicking every 3 or 4 seconds! It's not my board - one is a brand new one and the other came back from mega micros who couldn't duplicate the problem. Keven from MM said to change out the main motor. But having a hard time believing that because this is happening on both machines.
Any ideas?

[SplashN'Crash]

That's what fixed mine. - New main motor. Another time it was the tail motor.

[CaptHal8HS]

��Ok. I tried a new tail motor on my long-tail mCPX with the newly refurb'd board. So I'll replace the main motor on that one and report back.

[CaptHal8HS]

So I replaced the motor with a used one from a spare parts bag I received from a buddy and no joy. Tail still kicks. Now, his motor sounded more tired than mine! So I think I'm going to try it again with a new motor just to be sure.

[CaptHal8HS]

I pulled out the motor spare and put in the original. Then pulled the head apart and noticed a broken main shaft. Replaced it and all is good! Flies great once again.

[Saltnpeppa]

Capt,

I had this problem on the weekend with my mcpx. Even though the servo wires are plastic coated, I simply separated all three servo wire pairs to make sure they aren't touching. Fixed my twitchy rotation right away.
I can't explain why, but it worked.

[kona0915]

Originally Posted by CaptHal8HS

I pulled out the motor spare and put in the original. Then pulled the head apart and noticed a broken main shaft. Replaced it and all is good! Flies great once again.

Vibration from a cracked main shaft is pretty common problem which will give you the issues you were having. If you haven't I'd get the microheli solid main shaft. It's worth the few extra dollars. Also upgrading the head, blade grips and feathering shaft to the ones for the brushless MCPx is a phenomenal upgrade and you can still use your same blades and swash links.

[TexanPilot]

Any kind of vibe will cause this problem.

With my brushless modded MCPX, I get this problem even if the battery isn't all the way in the holder.

And +1 on the MCPX-BL rotor head, grips, etc. That feathering shaft is much sturdier than the stock non-BL one. And it has allen wrench heads on both the bolts!

[CaptHal8HS]

Interesting. Didn't know you can do this! Thanks!

[vtown nick]

Originally Posted by TexanPilot

Any kind of vibe will cause this problem.

With my brushless modded MCPX, I get this problem even if the battery isn't all the way in the holder.

And +1 on the MCPX-BL rotor head, grips, etc. That feathering shaft is much sturdier than the stock non-BL one. And it has allen wrench heads on both the bolts!

1+ on the bl head assembly.

The v2 is famous for doing the tail kick randomly when vibes are present. Go over the heli and check it for vibes. It should be smooth in your hand zero pitch and full head speed.

[CaptHal8HS]

Cool! Thanks for all the help! I also noticed on one of my mCPX's that the main gear had a stripped out inner "D" hole. Replaced it and all is well!
Now on to my other mCPX to try and figure out what's up with that one!

[Birdstrike]

Using HH Solid long throw boom?

Check the tail motor! get some leverage and attempt to push it out of the case.
If it moves, just get some glue and secure it well.

Hard to believe this problem is still around?