My 120 SR SUCKS!

[KellyVB]

I got a 120 SR last year and I had bad TBE out of the box and it still has it after several rebuilds , Have replaced all the odvious stuff, watched all the videos I could find to NO AVAIL This POS is almost uncontrolable, It's no fun at all to fly. I don't know why anybody would praise it at all. As a matter of fact I dont know why anyone would waste good money on it.

I'm wondering if anyone else has had the same isues with this crap heli

[DeGrizzle]

I wish I could help you, but I am having the exact same thing. I can fly this thing a bit by constantly correcting, but eventually this thing is spinning out of control. The other thing I'm seeing is when flying forward, once I let go of the throttle, this thing backs up 20 feet or so before leveling out on fast flight, unless I correct it. Sometimes it drifts waaayy left or right as well. This is inside in a big warehouse with no wind.

Also slight buzzing noise coming from the tail rotor... Not sure if normal.

All of this on a brand new heli with less than 10 flights on it. Bound to dx6i using john salts reccommendations, zip tie mod, 500 mah 25c batteries.

[KellyVB]

Ya, Its A POS, I did all that to. I gona unload it, Puttin no more money into it, BTW, just got thru flying my 500 3D, now theres a Heli

It's a POS inside as well as outside, the slightest puff of wind blows the thing all over the place.. Funny, I had a Blade SR, It was a POS too

[Dutchdrifting]

If you are in fff, the motors power is going towards moving forward and providing lift. If you then suddenly pull the nose up in fff, the power that went into forward movement becomes extra lift. Every heli has this tendency. While pulling up, you can reduce lift by reducing throttle. Every heli has this tendency, fixed pitch flybar heli's more than collective pitch heli's.

That it doesn't work outside in a breeze is logical. Again, it is a fixed pitch. Due to the blades always havind pitch, it gets bounced around by the wind. A collective pitch has a much flatter rotor disc with less pitch while hovering. Makes it more windresistent.

I have three 120sr's they all have tbe, when i give the controller to a lesser experienced friendof mine. On one I actually had tbe and when I tightened up the blade grips it was gone. Most times the tbe is pilot input. Chasing the heli.

Love my 120sr's

[WV_Medic]

What kind of problems are you having? I have worked on quite a few of these before. What kinda transmitter are you using?


Sent from my iPhone, I'm on the move!

[jondrew]

Interesting you're having so much trouble when apparently you've got experience with bigger helis. I've had my 120 SR for a month or two and have virtually no previous experience. I does drift to the left which I think is normal due to the tail rotor power. But I fly a lot in my garage/living room doing hover tail in, tail left/right and from the perspective of being a novice it seems very stable (and I have crashed it many times and have yet to replace any major parts).

By the way, my tail rotor "buzzes" quite frequently. If you get close enough, you can actually see the vertical stabilizer vibrate like a reed. Don't know of this is normal or not, but it doesn't seem to adversely affect anything.

As far as flying outside, the slightest wind makes piloting an adventure. It will either sit there head into the wind barely moving or it wants to take off like a bandit the other way.

[j_mcdade]

KelleyVB,

I had the same problem with my 120 when I first had it. The members here got me squared away. Seems like you have replaced all of the common components that could be problematic. There are two other things you might want to check: 1) Are your links on and facing in the proper orientation? They are designed to go on one way. Also; 2) you may need to mechanically trim your lilttle 'copter. Here is a link to assist with that endeavor. https://www.helifreak.com/showthread.php?t=494280

Good luck,

Jim

[JonJet]

I've flown the 120SR from almost day one since I started...

Some problems can be difficult to track down, but they can be fixed

The 120SR is a solid platform, one of the last FB heli's in the blade lineup...evidently, it's still a good seller because it's longevity has been tested

Ideal for indoor flying such as a gym, the 120SR cannot handle much of a breeze unless you are a top-flight pilot...it's been a go-to medium between the smaller FP's and CP trainers for years

I've played with various extended boom lengths, and found that 1" seems to be plenty to give a bit more rudder control and tail authority...I've even used the plantraco prop

[airshot]

Picture a small boat in a large pool of water, if you push the boat along then stop the motor it will continue traveling from its momentum, the same for turning. Your heli is the same way, the air acts like water, there is not much resistance so the vehicle keeps moving. As far as being inside a building... yes there is a breeze even if sealed up tite...your heli blades make the breeze as it is flying. Continued TBE is pilot error by constantly chasing the heli. Remember every action taken while flying requires a reaction to cancel the action, in other words if flying in FF you must go into reverse for a second or two to cancel the forward flight, same for turns. All this is called flying your 120 SR. Just normal stuff.......

[JonJet]

+1



Much more fun when you learn to fly, rather than learning how to keep from crashing

[Jonnie Fraz]

Originally Posted by JonJet

I've flown the 120SR from almost day one since I started...

Some problems can be difficult to track down, but they can be fixed

The 120SR is a solid platform, one of the last FB heli's in the blade lineup...evidently, it's still a good seller because it's longevity has been tested

Ideal for indoor flying such as a gym, the 120SR cannot handle much of a breeze unless you are a top-flight pilot...it's been a go-to medium between the smaller FP's and CP trainers for years

I've played with various extended boom lengths, and found that 1" seems to be plenty to give a bit more rudder control and tail authority...I've even used the plantraco prop

Jon,

When you extended the tail boom did you try to re balance the heli? In the tips and tricks for the sr Imzzaudae suggests "
It is imperative that you check the helicopter CG and mark all of your batteries before you continue onto the next step of this setup!" I found that I could not get perfect CG with a 1" extended boom.

[JonJet]

Originally Posted by Jonnie Fraz

Jon,

When you extended the tail boom did you try to re balance the heli? In the tips and tricks for the sr Imzzaudae suggests "
It is imperative that you check the helicopter CG and mark all of your batteries before you continue onto the next step of this setup!" I found that I could not get perfect CG with a 1" extended boom.

As far as an actual CoG balance, no...I did add a bit of nose weight inside the canopy until the heli would react about the same at a somewhat stable hover...usually somewhere in the range of a 5/16" nut deep in the nose seemed sufficient

The broader result was as I stated...an increased measure of tail control
I also use a longer battery with a higher C-rating than the stock version

[Pfloyd]

If you don't like it, you can send it to me as a gift for my 65th birthday next month!

[Jonnie Fraz]

Originally Posted by JonJet

As far as an actual CoG balance, no...I did add a bit of nose weight inside the canopy until the heli would react about the same at a somewhat stable hover...usually somewhere in the range of a 5/16" nut deep in the nose seemed sufficient

The broader result was as I stated...an increased measure of tail control
I also use a longer battery with a higher C-rating than the stock version

Awesome! Thanks for the info.
I have four sr120's at the moment, two fully blinged out with RKH kits and two stockers. One is someones nightmare that I am trying to get back flying, one is someones pride and joy, that they no longer had time for. The stockers fly fine...it is the nightmare that makes me want to blow it up....lol. On that one the new 5 in one board seems to be acting up... Hopefully it did not die on me.

[Imzzaudae]

120SR SETUP, SERVICE & FLYING LINKS FOR NEWBIES
https://www.helifreak.com/showthread.php?t=496890

[jp0160]

Originally Posted by KellyVB

My 120 SR SUCKS!

So does mine! And most everyone else. It hovers, thats about all its good for. Just put a fresh tail motor on mine and now I have massive TBE, like 5-6 foot circles. They are also fairly useless outside, they just don't have the oomph to combat any wind

[Imzzaudae]

120SR is a very low powered basic trainer and it is not intended to be flown outdoors or in any wind conditions period.

The links bellow will offer some setup and service help for guys having problems!

120SR SETUP, SERVICE & FLYING LINKS FOR NEWBIES
https://www.helifreak.com/showthread.php?t=496890

Read this as well.

TRIMMING 120SR
https://www.helifreak.com/showthread.php?t=494280

120SR TBE or Toilet Bowling
https://www.helifreak.com/showthread....71#post4708871


PE - Pendulum Effect and the 120SR
https://www.helifreak.com/showthread....17#post4711517

Hope this helps.
Ron

[Pfloyd]

Spend $10 and get J. Salts e-book. It has the 120SR. MSR, and MSRX setting with awesome tricks and tips. He explains in full detail of what the settings do. My 120SR flys like a beaut. No TBE, PE or anything. When things do get that way, I rebuild the upper rotor head components (especially the links) and all returns to normal. I stay away from bling and fly stock!

[Jonnie Fraz]

Thanks Ron! I have been through all your tips and tricks, and they have helped me out a bunch. One of my main issues is all of my 120's are used and trying to find out in what condition they are all in is a task. Your knowledge that you shared with us has been great, and I would be pulling my hair out without it.
Pfloyd, I think my two Blinged out 120's will end up being show pieces and I will fly the stocker.

[jml79]

I have found two types of TBE on my old one. If you are expecting this heli to hover staying put, don't. Learn to actively fly it. This will help you in the long run. If I can trim an 120 SR to hover hands off for a second or two and correct it's TBE then it's flyable.

The second TBE I have experienced was caused by stiff links/flybar. This caused the heli to be almost unflyable because the flybar actions were out of phase to far and you were always chasing and over correcting.

I am currently teaching the guy who bought my 120SR and it has a bit of TBE but it's controllable. I think a slight instability is a feature. He'll be ready for a CP and not surprised that it doesn't just hover.

Also check for a sticking servo. I have had that issue as well.