General S107C RC Helicopter Loses It's Balance

[JohnnyP]

Hello,
Sorry if I put this topic in the wrong section, I'm just new here. Anyways, lately I found my good old RC heli that I remembered I stopped playing with it after it hit the ceiling and fell because ever since, everytime I try to fly it, loses its balance. But now I really wanted to start flying it again and really wanted to fix the problem. When I start to lift off slowly, the heli starts to shake and then when I put a bit more throttle into it, it would just lean to one direction and lose all its balance. I can't lean it back because my controller can only control the turn of the heli and whether it will move forward or backward. Also, I believe many will ask me if I have both buckles in tact and I do. Can anyone help me please?

Videos of heli when taking off:
Rc Helicopter S107C Loses Balance (1) - YouTube
RC Helicopter S107C Loses Balance (2) - YouTube

Pictures of heli:

 

[holtneil]

Hi mate is the fly bar ok not broken it should move easy if one of the lugs are damaged the fly bar will not be able to do its job

 

[JohnnyP]

When you say fly Bar you mean the weight Bar that's on the really top? And what do you mean by on of the lugs are damaged? In which way?

 

[Admiral]

From memory all of the Co-axials that I ever owned only had one linkage from the top rotor to the flybar (weight bar) so that it could move freely, they always had the capability but the second one was never fitted.

Did you fit the second one thinking it had fallen off?

 

[Smoggie]

The fly bar (the bar on top with the weights at the end) must be free to move with virtually no friction. It should be really difficult to get it to sit level like you have in the photo because it should always be ready to flop to one side or the other. If there is any stiffness in the linkages that prevent the flybar moving freely you get the sort of problems that we see in the video.

The Syma 107 does have two links fitted as standard (others only have one).

 

[JohnnyP]

From memory all of the Co-axials that I ever owned only had one linkage from the top rotor to the flybar (weight bar) so that it could move freely, they always had the capability but the second one was never fitted.

Did you fit the second one thinking it had fallen off?

No, it was already connected. I also tried to look up a fix for the problem i have and for the exact same model and many people told others that one of their linkages/belts had fallen off so I believe mine should be fine. I also never tried replacing any parts so the heli that you see now should be the same exact one from when I bought it. Unless a piece had fallen off...

The fly bar (the bar on top with the weights at the end) must be free to move with virtually no friction. It should be really difficult to get it to sit level like you have in the photo because it should always be ready to flop to one side or the other. If there is any stiffness in the linkages that prevent the flybar moving freely you get the sort of problems that we see in the video.

The Syma 107 does have two links fitted as standard (others only have one).

Well it usually does lean to one side. I just balanced it for the photo so it'll be easier to see and understand all the parts and it'll be more organized. But usually it's just leaning to one side and it moves pretty smoothly. I'll also film it later to show you that it moves pretty smoothly, unless it needs to be smoother. But if that's actually the problem, you have any fix for that?

- - - Updated - - -

And also when I hold the heli and turn up the throttle, if I tilt it to the side, from what I remember (I'll check it tomorrow), the balance Bar stays parallel to the ground and not the heli

- - - Updated - - -

And thanks for explaining what the fly Bar is, I just don't understand anything in RC helis to it was a hard time for me to understand some of the stuffs

 

[Smoggie]

The flybar should flop from side to side without any resistance at all. The blades must also be free to pivot in their grips.

If there is any stiffness you just need to figure what part is causing it and correct it, It could be the pivot pin that the flybar or blade hub swivels on or it could be the links. if you disconnect the links you will be able to see whats causing the stiffness (if there is any).

 

[Stambo]

To be brutally honest and fairly blunt, I would invest very little time or money in to this machine.
Coaxial helis are very limited in what they can do, outside in the slightest of breezes it will get blown away.
If you intend getting further in to flying helicopters I would recommend something like a V911 or similar.
They are cheap, small enough to fly inside, can handle a little bit of wind and will teach you a lot more about how to fly a heli.

 

[Tony]

+1 to what stambo stated above.

 

[JohnnyP]

The flybar should flop from side to side without any resistance at all. The blades must also be free to pivot in their grips.

If there is any stiffness you just need to figure what part is causing it and correct it, It could be the pivot pin that the flybar or blade hub swivels on or it could be the links. if you disconnect the links you will be able to see whats causing the stiffness (if there is any).

I filmed myself moving the fly Bar to show how smooth it is, but ifrom it needs to verify smoother then tell me. I also took off the buckles between the fly bar and the propeller and I noticed that the propeller moves really smooth, but the fly Bar is a bit more stiff from it.
Syma S107C Flying Bar - YouTube
In the video below I just show the propellers in slow motion in case it'll help anyone to see if there's a problem.
Syma S107C propellers and flying Bar in slow motion - YouTube
And in this last video I show how the flying bar reacts when I tilt the heli. It always turns parallel to the heli so idk if it's supposed to do that or not:
Syma S107C Flying Bar In Slow Motion - YouTube

BTW, if I need to loosen up the flying bar and make it smoother, how do I do it?

To be brutally honest and fairly blunt, I would invest very little time or money in to this machine.
Coaxial helis are very limited in what they can do, outside in the slightest of breezes it will get blown away.
If you intend getting further in to flying helicopters I would recommend something like a V911 or similar.
They are cheap, small enough to fly inside, can handle a little bit of wind and will teach you a lot more about how to fly a heli.

Sounds nice, I might buy it. But the only con in it is that it doesn't have a camera while the one I have atm does have. Also, how will it teach me more about how to fly a heli? Like, what's the difference, except the fact that it has one propeller.

 

[holtneil]

Hi mate the fly bar looks tight to me its ment to be so free if you blow on it, it will move , try and lube it with some very light oil and get it really free so it will not sit in the middle like it is now, the fly bar should drop to the side if you let go of it

 

[Stambo]

Sounds nice, I might buy it. But the only con in it is that it doesn't have a camera while the one I have atm does have. Also, how will it teach me more about how to fly a heli? Like, what's the difference, except the fact that it has one propeller.

Your 3 channel helicopter has channels for throttle (up and down for altitude control), forwards/backwards (pitch) and rotation (yaw).
You have no sideways (roll) control so if you drift sideways toward something you have to rotate first then move forwards or backwards.
It uses that small tail rotor to tilt the helicopter to go forwards or backwards so is limited in it's ability to overcome the slightest of breezes.

A 4 channel helicopter like the V911 will allow you to drift sideways, it uses the tail rotor for yaw (rotational) control and to counteract the torque of the main blades.
It uses servos to change the angle of the blades for movement in any direction.
It is also capable of far greater angles therefore giving greater control in wind and higher speeds.
Most controllers will have variable rates to allow more or less angle and therefore speed.
These are the recommended beginner heli and most are self leveling.
The smaller ones are generally fairly robust (My son and I try to knock each other out of the sky with them).

A 6 channel or CP (collective pitch) helicopter is a far more complex beast that is capable of everything a 4 channel does and more.
They use blade pitch as well as motor speed for altitude and speed control.
With the right hands on the transmitter they can fly upside down and do all sorts of insane stunts.
Although very similar to a 4 channel control wise, they are harder to fly, more expensive to repair and generally come in larger sizes as well.
Modern gyros are making these easier to operate but still not recommended for a beginner.

A camera on a helicopter is generally a jello recorder, if you want to take aerial video I would suggest a quadcopter.

I hope this helps.

 

[D.O.G.]

Nice job explaining Stambo .

 

[JohnnyP]

Sorry I forgot to reply. I just wanted to say thank you for everyone who helped. I figured out what the problem was, the nail/screw that held the fly Bar was bent somehow, so I straightened it's and inserted it's back. Sure enough it didn't tip over right away, but it would still kinda move in big circular motions and would barely lift, just fly up a bit for a second and then fall right back down. Anyways, I read what Stambo wrote and I might buy a new and better heli like the V911 he suggested. I just thought it would be nice to fix an old toy of mine and maybe save some bucks. So thank you again for all who helped!


(BTW, although I might buy another heli, if anyone has a fix for the circular motion problem and the lift off problem, I would bet very thankful. Thank you in advance)

 

[Tony]

If you are not getting enough RPM to lift off and actually fly around, you may have a bad battery. And if this helicopter is as old as I think it is, then that is likely. Just find the voltage of the pack and match it to one that is close. Lipo is best and will give you improved performance. But just remember to keep it about the same weight and definitely keep it the same voltage.

 

[holtneil]

Hi glad it's nearly sorted like Tony said battery is old and may need to be replaced
I had 2 x V911 helis great fun to fly you learn more then with the coaxle .but our first heli hold memories I still have my syma 107g and my V911 are now teaching some one else to fly

 

[eyemdee]

I know this is a very old thread but for anyone interested I am putting together a guide to repairing all S107 R/c helicopters. I have one which is now 13 years old and still flying. Further information here