N5C TAIL TWITCH

[bclark]

Hey, I have a N5C that I purchased used. I have been working on a tail twitch for a while now with no luck. It has an Align DS-650 servo and a Microbeast FBL. The twitch movement is irregular, so I won`t call it wag. I have worked with the gain high and low, but can`t tell any change. For starters, can someone tell me what the servo ball distance is supposed to be. Any other suggestions would be appreciated also. Thanks, Bill C.

[DUCDOC]

Torque tube bearings
Engine Rear Main Bearing
Clutch stack bearings
Main Shaft Bearings

Check these first and report back on your findings.

[boogie12]

If none of those suggestions work check your tune on your engine. Running overly rich can cause your tail to twitch also.

[bclark]

Thanks for the replies. I don't have torque tube, mine is belt version. I will check the bearings hopefully this weekend. I will report my findings. I have tweeked on the tuning, just being careful not to get too lean. Haven't seen any changes yet. Thanks again, Bill.

[bclark]

This is an update on my tail issue. I decided to fly it today before taking it apart. At the field , my friend and I found a loose ball on the rear bellcrank. I tightened that and also worked on the tuning quite a bit. Nothing made any change in the tail. We also found clearance in tail output shaft brgs. to the fin and tail box plate. Tonight I took the heli apart and found the top mainshaft brg. bad. Hope that's the problem! I ordered the parts from Botos, but the fin is discontinued and the box plate and brgs. are out of stock. Does anyone know where I can get these parts or if there is an upgrade by another company? Thanks, Bill C.

[DUCDOC]

N5cTT tail fin will work

[bclark]

They actually had the fin and brgs. at Botos. Didn`t have plate on other side though. Matt told me how to tighten up the fit of the brgs with ca glue. I didn`t realize I was buying a discontinued heli! Has anyone done a TT conversion? Or is it not worth the cost of buying all the parts?

[DUCDOC]

I have both versions as there used to be a conversion kit. It costs a little more to convert one, but once it's done you have the latest version. I run shorter swash turnbuckles than stock so the head on my N5c is lower than most. I hook the head onto the upper bolt hole on the head. I am not sure if it's worth it as they both seem to fly about the same but the torque tube version does seem a little snappier than my belted version. Either way you will be happy with the N5c and don't worry it's not discontinued just updated. Fly with confidence it's a Synergy! Now the first Synergy is the N9 and it is discontinued. I finally got my hands on one and I refuse to fly it, so it sits on the shelf like a shrine in my heli cave.
The heli in my avatar is a N5c belted version and is the heli I mainly carry in the truck daily alongside an N7. NITROOOOOOO!!!!!!

[bclark]

DUCDOC, if I understand you correctly, there was a conversion kit but not now? I suppose it can be done by purchasing the parts individually? I guess I'm good for now with the belt, but would like to know what I need to convert. Thanks for the help. Bill C.

[DUCDOC]

Auto rotation gear
Tail case and umbrella gears
Front transmission assy and gears
Torque tube assy, bearings and holders
Updated tail fin

You can find the manual for the conversion at synergyrchelicopters.com

[bclark]

Thanks for the info on the parts DUCDOC. For a update on my repairs, bearings replaced and back together. Tested yesterday, tail may have been a little better, but definitely not smooth. I am now back to tuning, made 5 flights, leaning each time. I have a jeti with temp telemetry on the engine. Engine is running about 160 deg. F max. Back when I first installed the sensor and happy with the tune, it was running around 180 deg. Ambient temp was about 30 deg. higher. Any ideas on how much ambient temp changes the engine temp? Bill C.

[DUCDOC]

Ambient temps will wreak havoc with engine temps. This is where experience comes into play with tuning by sound. The colder the temps the more power the engine will make, but engine temps may not rise because of the cold cooling air from the fan.

[bclark]

Hey guys, I`m back to working on my N5C tail problem.
The couple of things I have done: Found the belt drive pulley not clamped tightly to the mainshaft, fixed that. Tightened the belt.
I have also disabled the gov in normal mode in order to try to get the engine tuned correctly. I am using a 3 point throttle curve with a Jeti radio. I`m having trouble trying to figure out if the curve needs work or the carb needs tuning. Engine revs at end of climb out when pulling back collective.

Today I made 4 flights, adjusting on the engine. Seems to run ok, but still have some tail twitch, although it may be better than it was when I last posted.

My needles are set at; mid, 1/2 turn plus 2 clicks, high, 1 1/2 turns plus 1 click. It is an OS 55 hz. The temp today was 70 deg.

Anyone have any ideas on my next attempt?

Thanks, Bill C.

[boogie12]

Your mid needle seems like it may be too lean. Stock settings for the mid should be at 2 turns I would try to make it a little richer than 1/2 a turn. That may explain your surge in rpm when backing off of the throttle.

Are you able to get a short video of the twitch so we can better understand what's going on?

[bclark]

Originally Posted by boogie12

Your mid needle seems like it may be too lean. Stock settings for the mid should be at 2 turns I would try to make it a little richer than 1/2 a turn. That may explain your surge in rpm when backing off of the throttle.

Are you able to get a short video of the twitch so we can better understand what's going on?

Do you think it should be closer to 2 turns? I have put over 130 flights on it since I had it. Hard to believe I haven't messed it up.Is the high needle in the ball park?
I will get back at it tomorrow, work got in the way today!
I will see if I can get the video. Getting it on here might be another story! I have a friend who might be able to help me.

Thanks for the help!

[bclark]

I just checked and I have the 55hzr. I didn`t get the OS manual, so I looked up the settings. It says 1 turn out on the hzr and 2 turns on the hz for the midrange needle.

Do you still feel that where my mid needle setting is now is too lean?

[bclark]

I apologize for the incorrect information. I didn`t know there were different versions of the OS55.

[boogie12]

No that's probably ok it depends on your location and the outside temperature. Up here because it's pretty cold I'm a little over 1 turn. What is your v curve set at percentage wise in the transmitter? If the center point is pretty high that would make it seem like the engine is overspeeding when unloaded. You may be fine as long as engine temperatures are in check and the smoke output is good.

As for your tail twitch how is your BeastX mounted and also would you happen to have a spare tail servo or maybe able to borrow one from someone? I had a Align ds650 on the tail of one of my helis and I could never get it to hold well and eventually it failed. But having a video would help a lot because right now we're grasping at straws for a solution.

[bclark]

Originally Posted by boogie12

No that's probably ok it depends on your location and the outside temperature. Up here because it's pretty cold I'm a little over 1 turn. What is your v curve set at percentage wise in the transmitter? If the center point is pretty high that would make it seem like the engine is overspeeding when unloaded. You may be fine as long as engine temperatures are in check and the smoke output is good.

As for your tail twitch how is your BeastX mounted and also would you happen to have a spare tail servo or maybe able to borrow one from someone? I had a Align ds650 on the tail of one of my helis and I could never get it to hold well and eventually it failed. But having a video would help a lot because right now we're grasping at straws for a solution.

Just got back from the field, my friend and I worked on the curve as well as the tune, and I`m satisfied that I`m close with the tune. If anything I may be a little rich. Smoke is good and engine is not hot.

The beastx is mounted on the top plate above the cyclic servos. One of the first things I did was change the tape. I believe it was the red 3m tape.

The servo doesn't feel right if you hold your finger on it and move the stick. It has a slack feeling when it moves by the center position. My friend is going to check and see if he has a servo to try.

We took a video of the tail, but he said you have to have a youtube account to put it on helifreak. At the moment I am not signed up with youtube.