So what is a MS011 motor ?

[S2Digger]

Some of you guy's may know that I've just started to build my first Hornet X-3D, looking at the instructions I note that:-

There is no motor pinion included in the kit, thanks to Dark horse I know that they are 64 DP pitch but what amount of teeth on the pinion would you you guy's recommend ?

Which leads me to the next question:- the motors rev's per volt is indelibly linked to the pinion used. The kit instructions recommend a "MS011 brushless motor", but they don't tell you RPV it is....

So I'm rather in the dark about what combination of motor RPV and pinion to use to stand at chance of getting the head speed right.

Of course the battery will be 11.1 volt.

Can someone help me to fill in the blanks in the instructions.....

Thanks John B.

[DarkHorse]

Hi, this is what info you need...

MS011 is also know as the MS Twister / Tsunami / Axi 2208/20 (gold) / EM300/20

1820 rpm/V, 8 - 12 A (>75%), max 16 A/60s, 45g, 27,7x26 mm, Shaft diameter 3,17 mm

Normally I would expect the pinion to come with the motor, I would ask the supplier where it is?
MS011 MS Brushless Twister Motor for Hornet w/gear


The recomended pinion is 25T on a 180T stock gear. This gives an economic ~2500 rpm head speed with the correct throttle and pitch curves (11.1v). I use a 27T for a ~2900 rpm zero pitch rotor rpm which give better cyclic responce for faster moves. To fit a 27T pinion you have to remove a portion of the frame to alow the pinion teeth to rotate freely, where as the 25T just fits. You may have to remove a small triangle shape from the front cross member landing gear strut for the motor to better seat.

(1820 rpm x 11.1v)/(180T/25T)= 2806 rpm at 100% throttle with no loss. Reality is ~2200 rpm at 9v, ~2800 at 12.6v zero pitch.

(1820 rpm x 11.1v)/(180T/27T)= 3006 rpm at 100% throttle with no loss. Reality is ~2500 rpm at 9v, ~2993 at 12.6v zero pitch.
Duration is slightly down due to the extra drag and current required to swing a higher head speed.

I got this 27T from TowerModels, it's a single grub screw 3.175 mm (1/8 inch).
Try these 64 pitch/0.4 mod suppliers list here.

[S2Digger]

Thanks DH,

Spot on again with your info, good job !

Here's something to think about I also bought the 3 bladed head conversion from the states, (couldn't resist it !   ). The 3 blades & holders are identical to the blades/ holders used with the 2 blade head, the conversion kit also comes with a 17 tooth pinion ! Reading the instructions it say's that this pinion must be used in conjunction with the 3 blade head due to, I quote:- "the lower energetic demand of this rotor compared to the original".

So if we take the motor suggested (MS011) and the gear ratio above we end up with:-

11.1v X 1820 = 20,202 by 180/17 = 1924  9v = 1560 12.6v = 2184.

I think it'll be a little while before the 3 blade head gets fitted, but the rev drop is quite large compared to the 2 blade head.

Thanks again John B.