Fast backwards flight, not holding, any ideas?

[s76 mech]

My little 250 is flying great, aside from the tail blowing out during fast backwards flight. On the 750 gyro I have tried both of my tail servos (290/9257). Both are doing the same thing. Flips, rolls, FFF, sideways flight, are all just fine. Both upright and inverted backwards flight is the problem. If I go slow, its fine, but add just a little speed and the tail blows out. Running a 16T, but it did the same thing with the 15T installed. I have the ball at 5mm on both servos. With my gear channel operating the gain, I have anywhere from 20-30% up to where it wags in a hover. I have tried setting the delay (on small helicopter) anywhere from O delay to full delay with higher gain values, no change. I have tried a C/F tail rod, and the stock rod with 2 guides, no change.

All I can think is it must be the gyro. Any ideas?

For any of you fellas out there that are having good luck in (backwards flight tail holding) with the 750 gyro, please chime in.

Thanks very much,
Rick

[Grant_beltcp]

Im using the gp750 and HSG-5084 tail servo and mine is holding awesome. I tried some fairly high tail slides the other day to see if i could get it to kick out and it was just solid the whole time. It even held well in sideways loops.
I have just set it up as per the manual with 0 delay (left stick in the centre).

[s76 mech]

I thinking its not the tail servo, I have the 290 and the monster 9257(which has more tq and spd). It does the same thing with both servos.

whats your setup, ball distance, which tail blades, gain, is there any slop in the tail grips, etc...

[Grant_beltcp]

Im running the 16t pinion, Tapered main blades and batman style tail blades. New hub/bearings from align and i have a little bit of slop, but not as much as the origional tail. The tail is really smooth by hand when not spun up, i havnt tried it with power on.
Ball is about 6-7mm max on the servo horn as thats where the hole was. Gain is pretty low, something like 20% real gain? 70% ish on the dx7.

My belts not super tight, but its not loose either. Everything else is set up as per the manual. Are all you endpoints right on the gyro? I didnt have to change them on the stock 420 servo, but i did with the hitec.

[s76 mech]

yeah, the endpoints are set okay. I didn't max them out, I figure there is about 1-2mm's of space at each end. good writeup on your setup. Will try the batman tail blades tomorrow, I haven't tried them in a while. Also will try moving the ball out a little.

thnks!

[DesertClimber]

Originally Posted by s76 mech

Fast backwards flight, not holding, any ideas?

I know, I know! Just go forward! Problem solved.

[s76 mech]

Going to shave down a set of the batman tail blades to 37mm tomorrow and see how she does.

I just read the post stating that align has some new tail blades coming out that are precisely that size and style, funny huh.

[blahblah9]

Be careful, mine held fine with the shave down blades to 37mm till i did a tic toc, and the tail let loose, but i didnt' have the new tailhub or bearings either, just warning you hehe

[DesertClimber]

Originally Posted by blahblah9

Be careful, mine held fine with the shave down blades to 37mm till i did a tic toc, and the tail let loose, but i didnt' have the new tailhub or bearings either, just warning you hehe

But your tail was never holding correctly.

How goes everything lately???

[blahblah9]

True, but it was holding fine after i trimmed it, throttle punches and flips it did okay, but tic toc it didn't like, so i was just warning u to be careful, but u don't have to take my word for it.

It goes good, i sold it, and bought a trex450 LOL should have it in a few days

[heli-on]

Too bad you didn't get to experience a good flight on one. My 450 feels like a 600 after whipping the 2-fiddy around.

I thought the better thing was max delay (stick all the way). My channel is reversed, so direction is opposite for red LED and won't stay red if I center the stick. I'm gonna try messing around with this before going 760.

[DesertClimber]

Originally Posted by blahblah9

It goes good, i sold it, and bought a trex450 LOL should have it in a few days

...was wondering where you were!

[s76 mech]

He couldn't handle the little guys, its just too much for him to handle! Sorry Ty, had to!

[blahblah9]

LOL i still got my gaui200 so not totally out of the little guy game HEHE

[s76 mech]

Ty, check out my other post. Maybe you sold it too quickly, this thing is a Maniac when you finally tame the tail and throw some Carbons on it, totally SICK !!!

[ndoren]

s76 mech,

I saw your other post.. Congrats on the tail lock-in! DesertClimber had similar success with the cut-down blades, but ended up going to a Spartan and that fixed everything. As it did for me.

I still think there's a fundamental issue with the gyro on this heli (not just the servo) that requires you to cut down the blades. That in itself leads me to suspect a problem with the design, but in your case you found a good fix. With the Spartan, I think you could bolt broomsticks to the tail to serve as blades, and the tail would hold. I'm back to the standard length batman blades with the Spartan.

Happy Flying )

[blahblah9]

Originally Posted by s76 mech

Ty, check out my other post. Maybe you sold it too quickly, this thing is a Maniac when you finally tame the tail and throw some Carbons on it, totally SICK !!!

WOW glad you got it to hold and doin good for you man, yea i might have sold it too quick, but u live and learn LOL i already have a gaui200 and after selling the trex250 i was able to buy a motor for my blade400 and have been having a blast flying it also (hadn't got to fly it in a month and half) anyways one day if money allows it i might get another trex250, by then they'll prob have a v2 HEHE as long as i got one 200 size heli i'm good. i will say this though, Being 3s i do love the power the trex250 has over the gaui200 with 2s, but can have had no prob performing any moves that i'm capable of with the gaui200, but more power always feels better HEHE Thats why i've been flyin my blade400 so much lately, i forgot how powerful it was

[s76 mech]

Being 3s i do love the power the trex250 has over the gaui200 with 2s, but can have had no prob performing any moves that i'm capable of with the gaui200, but more power always feels better HEHE

You should feel the power of 3S on the 16T (100%) with the new C/F blades, lots of pop there, like my old 3S 450 SE with a Scorpion Motor!

[blahblah9]

AWESOME!!!