gi1mo2

I am having issues with the tail rotor or gyro on my CP Pro 2. I had a crash recently, and replaced the rotor blade. I can't be certain, but the tail motor seemed noisier than normal (probably because the tail rotor was back ordered for a few weeks). I can hover quite smoothly, but after a few minutes, the tail starts to move in one direction (right I believe), and the sound seems different. I have to land because no matter how much rudder I give, it keeps going in that direction. If I land and take off after a few seconds, it seems to be ok for a while, but it will start again after some time. I also noticed that if I hover then apply full power, I can reproduce the same effect. I decided to replace the tail motor as I suspected it became hot, but it still behaves the same way. The tail rotor in on tight also.

Could I have damaged the gyro in the crash? Any other suggestion?

rotarydoc

gi1mo2,

Hmmm, you may have done some damage to the gyro, it sounds like it's a bit "drifty"....but you may want to try something else too, before you go that route...

You may want to play around with the proportional potentiometer (pot) on the 2 in 1....

This controls the ratio of tail to main rotor power....you can dial in more or less tail rotor per main rotor mixing with it.

You may want to note exactly where it is pointing before you start, so you can always come back to that "home base" setting...in case it makes it worse.

It will be trial and error, but I do know that a little goes a long ways, so just do small changes at first, and see how it does.

One method I used to use is to dial out all of the gyro, zero on the gyro pot, and then set the proportional by hovering just off the ground a couple of inches in little or no wind, and set the 2 in 1 proportional that way, (so that the tail stays neutral in a hover) and then return your gyro to a high setting (enough to cause a tail wag) and then slowly back off the gyro....this can be a bit tricky, trying to fly the heli with no gyro, so be careful or don't do it if you don't feel comfortable!![X(]

Hope this helps...

Glenn

gi1mo2

I think I figured out the problem, but need suggestions on how to correct it. I believe that the pinion on the motor shaft is loose and starts slipping when the motor gets hot. Why I think this might be the cause is that I have had to reposition the pinion on the shaft a couple of times. I was slipping out slowly. I 'knocked' it back in. Do I have to replace the whole motor? I don't have a puller. Any tricks on getting the pinion out and suggestions on how to make it tighter? Locktite?

The heli does hover nicely for a few minutes and then gets very twitchy, and if I throttle up, I loose control.

gi1mo2

Just an update - I still can't fly the CP Pro 2. I have changed both motors and called Horizon Hobby support who sent me a new 2 in 1 unit under warranty. Unfortunately, that didn't help. To confirm that it was not the transmitter, I bound the heli with it's original transmitter (bought an RTF) instead of the new DX7. No change. I bet it's the Gyro, but... Is there anything else I can try? Send it back for repairs perhaps?

I spent more in repair parts as the original heli price already. 3 sets of carbon fiber blades, 2 which were destroyed while trying to fix this problem.

Woody_99

My Feedback: (2)

You might try taking the gyro apart and see if the board got knocked loose. I have heard of that happening.
That's about all that is left from everything else you replaced. You didn't pinch a wire going to the tail motor, or a loose connector by the 2 in 1?

gi1mo2

I reached Horizon Hobby support this afternoon, and didn't get the same nice response as I did a few weeks ago. They couldn't offer anymore help or advice other than try to get someone else to fly my heli to help diagnose the problem. I might try a Telebee Gyro (I have a spare one) to see if it makes a difference. I won't try my new JR770 3D gyro - that's reserved for my HK450

gi1mo2

I guess I don't want to give up... I decided to try again. This time, I removed the main blades and started the heli to see how the tail would behave on a glass surface. I adjusted the gyro to be more sensitive, trimmed rudder slightly, and could hold the tail fairly well even with change of power. I did that for a while to ensure it was not a overheating problem. I put the blades back on, and powered up the heli. Toyed with it and because the battery was weak from the previous trial, I changed it and poweredup again. This time the heli held on a hover for 15 seconds, and all of a sudden, tail failure. This time, real failure. Was not very high and was able to land (hard). I tried the heli again, and no response from the rear motor. I disconnected the main motor, and powered up again - no movement. Tested power to tail, and there was power. So another tail motor. Perhaps the second one I got was bad.

Back to the repair table... (I need to find a better place than the dining room table )

Aframomum

My Feedback: (10)

Hey gi1mo2,

Let us know if you found what happened, kinda curious myslef as to what the problem is. However, sounds like a gyro issue (that may be crash related) if the tail is suddenly letting go after flying normal for a bit. Was it doing this before your original crash?

Mark

gi1mo2

Stopped by my LHS this evening, and bought a new tail motor, new landing skids, new blades and a few other items. I replaced the rear motor and powered up slowly and the tail seemed to behave better. I was able to hover nicely for a while and the same thing happened. Tail to the right again. I took a new Telebee gyro I bought recently, put it on top of the CPP2 gyro, connected everything to the new gyro and took it for a ride. It seemed better. I still have to play a bit more with it to give a final verdict. I did seem a bit better, but didn't have time to make any adjustments.

ejc34710

Also make sure the tail rotor is on the right way. I broke mine on my cpp2 and replaced it. When i went to fly it again, it would always spin out of control. After looking at it for a bit and thinking, i took the main blades off and tested the gyro by holding the heli in my hand and moving the tail to the left to make sure the gyro was trying to keep the tail straight. It was, but it didnt have the resistance it used to. I flipped the tail rotor around and it worked fine after that. I didnt think it mattered, but it does. Just thought i'd put that out there. Hope its fixed though.

gi1mo2

Udate - after a third replacement tail motor on my Blade CPP2 (I decided to try one more time after seeing that my new MSR with a tail motor could have a steady hover), I now have a very nice steady hover (2 batteries only). The last motor again failed. Wouldn't spin fast enough (going by sound), and rudder trim was R90+. With new motor, trim is R8 and it is very steady.

Gilles