Synergy 766 Build and Review - On Going Discussion Thread

[Chris Sexton]

Originally Posted by macdad

Another area that could be an issue is the ball link ends. They are pretty tight, and I didn't use a sizer on them. That could very well be the culprit. Since my gain setting changes make little impact, it leads me to believe there is a mechanical issue somewhere.
.

Absolutely, this will cause the servos to work harder and fine adjustments are more difficult.

[macdad]

Originally Posted by rb30cory

Which FBL unit and servos?

KST BLS815 brushless servos and Eznov Neuron. They were both used on my Avant Mostro and worked flawlessly.

[mverhorst]

I would get a Botos sizer and size those links...

[macdad]

Originally Posted by mverhorst

I would get a Botos sizer and size those links...

I believe that is my next step. I lowered the refresh rate from 333 to 200 on the FBL, and it seemed to help, but still not where I want it. I know the links are tight. I suppose it would be $20 well spent!

[rcnut]

I tried flying my N7 without sizing the links and it made for a very jittery flight. I bought the Botos sizer tool, when it became available (out of stock at that time), and now my N7 is smooth!

[rb30cory]

Got my replacement tail parts Friday and the 766 got 6 x 7s 1100 rpm flights and 1 1650rpm flight this weekend. Man I love this machine! What I do notice now is the air density boy flying close to sea level is nice.. but it is what it is here at 6000ft.

Hoping to head to the field again tomorrow after work for some more action.

I noticed today I've started flying faster with quicker stick moments and man even at 1650 rpm this heli covers some ground fast!

[rb30cory]

Got out to the field today. It was a bit windy - averaging around 10mph with some gusts above 15mph. I was having fun and decided to shoot some slow motion 766 3d action. I really love this heli. Its unreal how from 900rpm to 1900 rpm it just performs!

Synergy 766 Slow Motion 3d Flying - Pilot Cory (5 min 55 sec)

Hope you enjoy!

[mverhorst]

[Grimmy]

Originally Posted by rb30cory

Got out to the field today. It was a bit windy - averaging around 10mph with some gusts above 15mph. I was having fun and decided to shoot some slow motion 766 3d action. I really love this heli. Its unreal how from 900rpm to 1900 rpm it just performs!

Synergy 766 Slow Motion 3d Flying - Pilot Cory - YouTube

Hope you enjoy!

Love the slow head speed stuff! Good job!

[macdad]

Great flying! I need to measure the headspeed on mine. It is a lot higher than in your video, but still low for a heli this size. I would guess it is around 1600. It has great power and snap still.

I think the speed up tail gear is going on my Christmas list!

[rb30cory]

Originally Posted by Grimmy

Love the slow head speed stuff! Good job!

thanks, I do too - its relaxing and yet can be hair raising at the same time.

Originally Posted by macdad

Great flying! I need to measure the headspeed on mine. It is a lot higher than in your video, but still low for a heli this size. I would guess it is around 1600. It has great power and snap still.

I think the speed up tail gear is going on my Christmas list!

I normally fly on 12s at 1600 rpm. It flies for 6 to 6.5 minutes that way. It has plenty of power even at 6000asl.

Sped up tail gear was needed below 1800 rpm I felt. At least for me and how I fly. I have no tail issues anymore, even at 1100 rpm, just need to be a little more cognizant of hard movements that involve the tail.

[rb30cory]

Little fun in the Mexican sun today with a 766 in the middle of it all.

Synergy 766 - Turned Up! - Pilot Cory (4 min 24 sec)

This heli is freaking awesome.

[rb30cory]

It's been a while since an update. However I've been flying my 766 about 10 times a week on average. She has about 250 flights right now and I have yet to do any maintenance. However I have been flopping between 1100 rpm 7s flights to 1800rpm 12s flights and getting more aggressive.

Today before my flight I did more normal preflight check and noticed my tail slider was loose. So I tightened up the lock nut and bolt good to go..

So I'm about 3 minutes into my beating of the 766 coming across mid field on the bottom of a full collective power loop about 15ft up probably doing close to 100mph and in the middle of rolling the heli onto its back inverted for a wall where.. the tail just let's go! BOOM I can see the tail rotor blades stationary as the heli begins to start piroing like a tornado. The heli walled a bit since this happened in the middle of my maneuver and the disc was vertical to the ground going across the field. Thold it was and I managed to flatten her out as she was still piroing uncontrolled and managed to auto her while piroing over to the end of the runway for a safe soft landing.

If you can imagine I was ecstatic. This is the 3rd freaking time my 766 tail went out and 3rd successful save.. however today's was so violent and the speed in which it happened I was very very please to get her down.

Post flight inspection revealed the center transmission pin came out partially allowing the tail to spin free..



I will have to add this to my inspection routine.. I recommend others do as well.

Anyway all is good. What a great heli and a great day at the field.

[Grimmy]

Did you have it loctited in and it came loose?

[rb30cory]

Yes. It was actually green loctite and cleaned.. first thing I built. I do have a gov gain issue bc I'm overgeared for my headspeed.. it acts like a jack hammer and I think is why my tail stuff is coming loose.. I'll install the 12t pinion this week to fix.

[Rodney Kirstine]

That's great that you got it down safely!

[rb30cory]

Thanks.

I dug into her Sunday night. Fixed the pin and cleaned the components and re loctite the whole bit.

12t pinion is in now on so I won't be overgeared anymore.

Also I found I can't divide.. with the 13t pinion I had my gov ratio at 10.7 to 1 for the last 250 flights...it should have been 9.77... so my gov issues could potentially have been this over site..

Ratio is now correct at 10.58 with the 12t.

Now I am really looking forward to flying her to this weekend to see the improvements.

[lou70]

I'm also using a gear ratio of 10.7 with the 13t gear. 139/13 (Main gear/pinion). It appears you may be using the auto-rotation gear (127) in your calculation.

I'm surprised to see that the set screw with green loctite still managed to come loose. I will definitely have to keep on eye on this. Thanks.

[rb30cory]

Thanks Lou! Turns out I can divide just not read.

Yes I was surprised as well.. my gov has been acting like a jack hammer when it hits to keep my tail straight during hard collective maneuvers.. it did take 250 flights.

I'll be keeping an eye on it now for sure!

[jhamel]

Originally Posted by rb30cory

Post flight inspection revealed the center transmission pin came out partially allowing the tail to spin free..

Congratulations lading her safely. Consider also using CA on both ends of the pin.