Hi Guys, I'm a novice in this stuff. Help please? I have two new S111g. One of them had a crash and now won't lift properly. Just spins around, vibrates and goes backwards.

I found a fair bit of hair wrapped around the shaft (good way to clean the floor? - got to sell the dog!), opened and removed the hair. Reassembled but still same probs.

If I manually spin the balance bar the top rotors spin, but so does the lower rotor, and in the same direction. Of course the bottom rotor should be free flowing on manual and in opposite direction when on power.

I took off top rotor and balance and outer shaft, gave a clean, but no difference.

What to check next? Maybe this is a sign of bent lower shaft? Where do I look to find what is causing the drag?

Thanks for any advice, cheers

Please check my blog for "My S107 won't lift" and "Pivot Pin". Then we will take a look at this a little closer, okay?

Thanks Heli Pad, great blog and posts. Quite hlepful.

Think my problem is something other than what you described. When pwoered my S111g does not rotate as you described. It skates across the floor to the left at a fast rate of knots.

With power off if I rotate the top rotor the bottom rotor also rotatates, with a little whirring sound, in the same direction. Even with the chassis split open and nothing holding the shafts,

I have removed and cleaned the top rotor assembly and top outer shaft.

Something wrong with the bottom / main shaft? Top assembly not correctly installed (tho it seems basic enough)

The Pivot Pin looks ok

I have a second S111g that works beautifully.

Appreciate advice, thanks

Alright, it was worth a shot, as the blog covers some of the most common issues. So, you have something else. That's what makes life interesting.

When you manually rotate the top blades, the bottom one follow in the same direction. You already know what that shouldn't be the case. So, I think something is binding the two systems together. A bent shaft is a possibility. Do they rotate at the same rate?

But when powered, they do go opposite directions. But with vibration? How bad is the vibration? That could be a sign of bent shaft. But the body of the S111 doesn't rotate? Indicating the relative speeds between upper and lower are the same. But probably equally slow/weak, therefore, there is no lift. It skates left at a fast rate. I'd like to see how fast it is doing it.

The best next step is to make a video of these things we talked about, so that I could see how the rotor turns manually, and how they turn when powered, and how fast it skates sideways across the room. A close up of the head with some manual movements so that I could see if the head is healthy would be helpful. You think you could do that? If you can't share a video, could you at least share a few close up pictures of the head assembly?

yep, when powered they rotate in opposite direction. When non powered on manual rotate they both rotate at same speed in same direction.

Yes, it vibrates fairly strongly.

So, bent shaft? Easy enough to remove and straighten (and how) or best to replace (and how)?

Thanks for such a speedy response

pic of shaft. even looks a bit bent...

Oh yes. That's bent alright. Coaxial shafts are one inside another. When it is bent like that, it inner will bind with the outer. That explains the two them turns the same direction in low speed. When powered (in high speed), they will turn in opposite directions. But they are each other's resistance - causing vibration and slower overall speed. That's why you don't get lift.

If I were you, I would buy the inner (main shaft) replacement part. But in the mean time, remove the head assembly from the top of the inner shaft, so that you could slide the shaft out from the bottom. Roll it on a flat surface to see how it is bent, and try your best to straighten it. It might not be 100%, but perhaps just enough to get by before replacement arrives.

At 2nd look, the outer shaft might be bent also. To remove the outer one. Grab the gear, twist shaft and pull. It's just friction fit. Do the best you can to straighten it. Best to replace it if it is bent.

GREAT!. A diagnosis and plan of attack.
Can you please explain how to remove the bottom shaft?

First, remove the head and pull out inner shaft from the bottom. Then you are left with one gear attached to the lower/outer shaft. This is friction fit. Just grab the gear in one hand, lower blade grip in another, twist and pull apart.

Are you stateside or down under?

Just outside Byron Bay, the eastern most point of Australia. Where are you?

This is the S111g so with the chassis apart I'll need to undo the 3 screws from the triangle and pull out the shaft that way?

I'm stateside, so our US sellers won't help you. Do you need help locating parts?

Yes, you need to remove the bottom triangle to gain access to the gears. Watch out for the two middle gears (smaller than the main). You shouldn't have to remove them, but they are held to the frame by metal pins. You could pull the pins to remove them. Note the directions of the gears.

I assume that you know how to remove the head? There are two locking screws just below the flybar.

yup, removing the head is ok. I'm also ok to get the shaft and bits. thanks for tip of the pins. I'll try repair tomorrow

Sounds good mate. Good night from here.

main outer shaft was quite bent too.
manually straightened them and now the manual rotation is fine, rotors spin much easier.
must still be bent more than I can straighten tho; only hovers above ground. but now does not skit where it shouldn't, and responds to commands except lift.

might get some silicone lubricant and see if that helps a bit

in the end think I'll need a new main outer shaft and inner shaft.

newsflash after full charge is working much better.
lifts but still has a little vibration