i'm a novice pilot who has hovered my cp2 in out of the box form. wanting to see how smooth i could get it to fly, i set out fine tuning it yesterday. it appears esky has added a ton of positive pitch at the factory (factory settings are roughly +5 to +25 in FM0 & -5 to +20 in FM1). so i adjusted for -10 to 10 degrees in idle up (FM1), which gives 0 to +10 in normal mode. after this fix, my cp2 started to have the notorious sudden blast off problem. you may have read about this elsewhere, but some ppl have taken their cp2s out, started to spin up, reaching nearly full throttle with no lift, then randomly the heli jumps up 10' high. i never had this problem until i corrected my pitch curve, so i decided to investigate closer to find out why. from my bench testing i observed these symptoms:

1) from spinup, near full power is reached and the collective doesn't respond. suddenly the collective kicks in, RPMs drop, and the heli rockets skyward (LED goes green to red the instant this happens)
2) vibration is noticed when cyclic is added at any speed in any mode
3) one blade was non-responsive to cyclic and collective, particularly at higher headspeeds
4) the non-responsive blade can be "brought temprarily back into track" with the application of cyclic. example: as collective is increased to some point, only one blade responds. the other blade is now out of track, but will go in track if the cyclic is tapped a bit. subsequent changes in collective result in the same behavior, requiring cyclic input to bring the "bad blade" in track.

by fixing the pitch curve to go -10 to +10 in FM1, the headspeed is greatly increased, but so is the centrifugal force acting on the bell hiller arm and its' linkages (hmm, maybe esky had a reason for the high pitch angle: it is one easy way to fix binding, nyuk nyuk nyuk. not laughing). it was apparent to me that binding caused this problem, so i went about trying to smoothen things out. all my ball links had up to 1.5mm of flashing from the mold that i had to remove and the some of the balls were molded out of alignment (i sanded these down a little). i also found that one of my bell hiller arms was binding on its pivot. the binding arm is not obvious on the bench, but if you mimick centrifugal force by slightly pushing the arm away from the hub, it binds a bit.

the only thing i could do to smoothen it out besides removing the mold flashing, is to lube the swashplate bushing with oil, and the bell hiller arms with silicone lube. it's a little more predictable now, but still vibrates on the cyclic. since my blades were only balanced statically, the next thing i'm going to do to smoothen things out is balance my blades the right way (right way=matching blade CGs, not just tape on the tip). i'll let you know how it goes.

my point is not to trash talk here. the cp2 is what it is: an inexpensive heli, and i love the way it flies when it's setup right. i just had some issues setting it up right and wanted to share them here. if anyone has tips to help with binding on plastic heads or any generally helpful advice with cp2/blade binding like better lubes, inexpensive mods..., please report them here.

thanks in advance!

You can balance the whole assembly in the helicopter, just loosen the coller on the main shaft and slide it down so the main gear disengages (or you can remove the motor). Then the whole assembly is balanced as one, this will give you the best performance.

Also make sure one of your blades isn't badly warped since you say its going off track. Make sure all your links are the same lenth at the 3 swash points. Make sure your flybar paddles are the same length and make sure feathering shaft isn't bent. Also make sure the links are not bent or bowed. Make sure theres no binding period, lightly sand as needed for smoothness. And make sure your blades are correctly balanced, even your tail rotor blade. If everything is properly set you will enjoy your heli. If something is off on my blade cp it lets me know right away. I know you have a honeybee but there almost the same except for your bellhiller head. I have a honeybee king almost ready to go in a few days with gear driven tail, no more tail motors to worry about I have noticed in the past when I was using woodies, that even nicking your blades at the tips my helicopter would wobble or not fly correctly so the blades have to match each other as exact as you can get them. Good Luck...Jimmi

YESS!!! I got everything working schweet!
thanks for the advice guys. i went over everything and here's what i found:

swash perpendicular to shaft (correct range of motion in both modes, no binding)
blades dimensionally symmetrical (no warping and similar stiffness in all directions)
flybar/head balanced on heli (on the heli as you said, by loosening the collar))
blades balanced & CGs matched (cg of both blades are located in the same distance from the grips, and balanced as normal)
sloppy movement of one of the bellhilller arms
sloppy movement on the flybar hub

after i tightened down the arm and hub screws, everything moved smoothly, but not as free as before. so i added silicone lube to all the friction areas and it helped a bit. now all my vibrations are gone and the heli hovers hands off for 3sec, instead of 0.5sec. it appears better to err on the side of more friction/less slop with bellhiller arms (versus more slop/less friction). i always knew helis need to be very precise, but man do i know what that means now! i had no idea what my heli was trying to tell me until now.

(jealousy) i was thinking about the hb king too, but it seemed like parts were hard to find. i bet that tail rotor is going to be way quicker, woohoo! i'm going to hold out with my cp2 until i can afford (and deserve) a Trex450se.

Congratulations Truglodite on freeing up your bindings and making it run sweet. For my honeybee king parts are not that bad I get them from balsa products or you can order from about 5 diffrent hobby webshops and you get your parts in a few days, not bad at all. I was thinking about the trex also but you should also look into the ark 400 a side by side review of both helis left the trex as the second best and I was impressed by the ark 400 which shogun parts will fit it also. I forgot to mention I just put a bell hiller upgrade on my blade cp and I had to take it out tonight and test it. Man is it sensitive and I know I'm going to love it. The throws are so much more responsive and I am happy with the setup. That was a new swash and blade grips and they weren't cheap and a new carbon fiber tail. The gyro needs more tweaking because the plastic tail just bends easily but the carbon fiber tail stays in one place and doesn't bend at all, a big diffrence I must say and the tail alone was 18.00[:@] The thing with the bell hiller arms you gotta keep your eyes on them seesaw arms because them screws get alot of movement and they can become loose and thats where slop comes in and ruins your day. Good luck in whatever choice you make as long as its a heli you'll be ok. Heli007

good to hear you like your bell hiller & tail setup. the added maintenance from the bell hiller arms doesn't bother me now that i'm aware of what was actually happening. it's worth it to see these helis roll like a fighter jet. you're absolutely right about those arm screws sneaking up on me to ruin a day. i just heard about those cf tails and was curious how thay performed compared to dd. your review sounds favorable to cf tails in terms of response. i'd imagine having the added stiffness and still using the gears would add to the acceleration of the rotor and make it respond faster as you have found. dd saves motors, but not sure if they'd be more sluggish than what you have. $18 is a bit much for a tail blade, but i might consider one before i go dd since i don't have much time to tinker lately. i'm pretty far off from adding another heli to my hanger at the moment, but the ark400 does look promising.