Hi, i'm having issues with a slow tail wag on climbouts. I already decrease/increase coll. precomp and nothing happens... using scorpion gov and vbar gov same issue, i left it on scorpion gov. Kst x1035 tail servo, 500hz frequency and Vbar EVO. The tail mechanics are not hard when i move. https://youtu.be/Rn9snnfDZAw Regards https://www.vstabi.info/forum/read.php?56,201574,201574#msg-201574 Wed, 13 May 2026 22:22:18 +0200 Phorum 5.2.7 https://www.vstabi.info/forum/read.php?56,201574,201738#msg-201738 https://www.vstabi.info/forum/read.php?56,201574,201738#msg-201738
Regards!]]> Marianovbar Logo 700/800 Questions Wed, 03 Apr 2024 04:58:30 +0200 https://www.vstabi.info/forum/read.php?56,201574,201722#msg-201722 https://www.vstabi.info/forum/read.php?56,201574,201722#msg-201722
that, plus the fact that the motor kV are usually only a ballpark figure.

My calculation would be, for a 12s drive, 535 x 44.4 V / 10.46 * .9 (load factor) = 2044 1/min sustained max. head speed from battery full to battery empty.

With a 6s drive, my empirical load factor would even be .8

There seem to be two ways, the European way, set up so the governor can maintain the requested head speed throughout the flight/battery, and the U.S. way, go full throttle and forget about it, and who needs a governor anyway ;)

In competition flying, there are, or must be, trade-offs, something in-between, for maximum performance as well as to get your three minutes' worth of flying time, as well as to protect the ESC, which has the least switching loss (and as a result, heat generation and dissipation) at full throttle.

Butt there are some given limits, like, you can not open throttle more than 100 % :) no matter if governed or if you set throttle manually.
And if the load becomes too high, collective/cyclic and tail combined, rpm has no other way than to drop.

Kind regards

Eddi]]> Eddi E. aus G. Logo 700/800 Questions Tue, 02 Apr 2024 08:59:42 +0200 https://www.vstabi.info/forum/read.php?56,201574,201706#msg-201706 https://www.vstabi.info/forum/read.php?56,201574,201706#msg-201706
Consider 3.7V/cell you used is the average voltage 50% full battery w/o load and efficiency calculated. So your estimation has some rework to do.]]> RV Logo 700/800 Questions Mon, 01 Apr 2024 11:27:36 +0200 https://www.vstabi.info/forum/read.php?56,201574,201705#msg-201705 https://www.vstabi.info/forum/read.php?56,201574,201705#msg-201705
So why less?

Regards]]> Marianovbar Logo 700/800 Questions Mon, 01 Apr 2024 06:17:21 +0200 https://www.vstabi.info/forum/read.php?56,201574,201703#msg-201703 https://www.vstabi.info/forum/read.php?56,201574,201703#msg-201703
=> less RPM for this gear ratio.]]> RV Logo 700/800 Questions Sun, 31 Mar 2024 22:54:28 +0200 https://www.vstabi.info/forum/read.php?56,201574,201700#msg-201700 https://www.vstabi.info/forum/read.php?56,201574,201700#msg-201700 Some advice to lower pwm scores?

Bigger blades and less rpm? lower gov gain? collective add?

Pics attached

Regards]]> Marianovbar Logo 700/800 Questions Sun, 31 Mar 2024 20:34:25 +0200 https://www.vstabi.info/forum/read.php?56,201574,201601#msg-201601 https://www.vstabi.info/forum/read.php?56,201574,201601#msg-201601
to be honest, no idea. The Wiehenstroth brothers are flying the 700 with KST servos, and definitely not material-friendly.
I must say I also never heard of broken belts, on the 700, yet.

Technically, I would say the motor by itself can not overspeed unless something is slipping.

On the other hand, your motor has nominally like 2.5 % higher kV (probably negilgible on it's own) but also like 15 % more continuous power so I _guess_, with the 14 T pinion, high collective angles and/or longer blades (710 instead of 690) you could be over stressing the mechanics, at least if you do most aggressive maneuvers without accommodating e.g. with collective management or going a tiny bit easier on the sticks.
It's not only that of course, but probably the combination, the servos driven harder, too, they just do, they don't ask or look left or right ;)

The governor setup could also be a tell-tale, those high-bred electric motors, powerful ESCs and high-C batteries also simply deliver, if you let them, without much in the way of easing off the tiniest bit.

It's not that the 700 mechanics (mostly the same as the 800 mechanics, by the way) are weak, but there's certainly a point where too much is too much.
That being said, I'm only saying, I can not tell. Even if I had that model at hand, my flying would never bring it remotely to it's mechanical limits.

I'll try and put Alex on this topic, maybe he has some insights. He's maintaining the models also for his brother Marik, if anyone knows, it's him :)

—Eddi]]> Eddi E. aus G. Logo 700/800 Questions Thu, 21 Mar 2024 09:18:12 +0100 https://www.vstabi.info/forum/read.php?56,201574,201595#msg-201595 https://www.vstabi.info/forum/read.php?56,201574,201595#msg-201595
This is why i mentioned to change from 14 tooth to 13, to fix the "overspeeding" and have the chance to increase my tail gain.

Another thing to note is, this issue started when i changed my servos from savox to kst, before that with the same motor and pinion didn't happened. Has something to do with?

Regards]]> Marianovbar Logo 700/800 Questions Wed, 20 Mar 2024 18:12:29 +0100 https://www.vstabi.info/forum/read.php?56,201574,201583#msg-201583 https://www.vstabi.info/forum/read.php?56,201574,201583#msg-201583
please elaborate on gear chatter, I'm hearing that for the first time.
In the video, I can't seem to ID any odd noises, but that might be because of my computer speakers, which are not very HiFi ... plus the wind noise and all.

I mean, pinion/main gear has next to no play, and it's under load all the time, the belt, is, too, as are the bevel gears.

It may be necessary to lower the governor overall gain, for current ESCs, but otherwise, also if the Torque-Precompensation is set properly, you should be able to run way higher gains and have no tail blowouts at all.

Kind regards

Eddi]]> Eddi E. aus G. Logo 700/800 Questions Tue, 19 Mar 2024 08:53:48 +0100 https://www.vstabi.info/forum/read.php?56,201574,201578#msg-201578 https://www.vstabi.info/forum/read.php?56,201574,201578#msg-201578
Regards]]> Marianovbar Logo 700/800 Questions Mon, 18 Mar 2024 17:04:59 +0100 https://www.vstabi.info/forum/read.php?56,201574,201576#msg-201576 https://www.vstabi.info/forum/read.php?56,201574,201576#msg-201576
is the wag getting worse with higher rpm?

i once had something similar and the problem were bad thrust bearings in the tail]]> florian_neuner Logo 700/800 Questions Mon, 18 Mar 2024 16:08:53 +0100 https://www.vstabi.info/forum/read.php?56,201574,201575#msg-201575 https://www.vstabi.info/forum/read.php?56,201574,201575#msg-201575 ulrich Logo 700/800 Questions Mon, 18 Mar 2024 16:08:03 +0100 https://www.vstabi.info/forum/read.php?56,201574,201574#msg-201574 https://www.vstabi.info/forum/read.php?56,201574,201574#msg-201574
Kst x1035 tail servo, 500hz frequency and Vbar EVO. The tail mechanics are not hard when i move.

https://youtu.be/Rn9snnfDZAw

Regards]]> Marianovbar Logo 700/800 Questions Mon, 18 Mar 2024 14:18:36 +0100