I'm planning to use Hextronic DT750 and 11*4.7 props. I feel that DT750 are efficient than sunnysky 2216 II-900kv

1.   Should I go for 450 or 550 frame ? I feel like 550 is more weight than 450.
2.   Incase if I'm using 450, can I mount FPV later. ? Is there will be much space to mount FPV ?
3.   450 or 550mm frame. Is that compatible with APM 2.6 ?
4.    Is that worth buying dt750 instead of 2216 11-900kv(efficiency wise). ?

I expecting more comments on this. confusing me

Hello! Subbiya...
1)DT750 are called work horse motors but it has been known to have issues like unbalanced motor bell, the connector breaking of and few more QC problem...SunnySky on the other hand are quiet and butter smooth motors...
2)If you plan to go for FPV choose a smaller kv motor with large prop as it is efficient and you'll be able to carry more weight
3)The APM is a controller..it doesn't matter if you use 450 or 550 frame only PID values will differ
4)People have been able to successfully mount fpv gear on ladybug so 450 is a huge copter compared to it..

750 with 11inch prop is good choice (18 amps to get 1100 grams of thrust per motor)

For for this motor with 11inch prop you should go for bigger quad 500mm or large

2216 is very very good in comparison with DT750, 2216 wins over efficiency, build and not odd prop mount size.

But DT750 gives a good amount of thrust if you compare with 2216 the only problem is the construction due its open bell construction dirt gets to stuck in the motor wiring or magnets and it might cause damage in long use.

I just love DT750 a lot it was the motor for my first quad, lot of thrust

450 or 550mm frame. Is that compatible with APM 2.6 ?

Compatible means here I'm asking about whether there is enough space to mount APM 2.6.

And, I can go with sunnysky 2216, 900kv with 11*4.7 ?

Yes you can use 11" props with sunnysky 2216 900kv but use 3S battery. My suggestions, go for larger frames as it will allow you to go for future upgrades. For FPV try to use lower KV motors with larger props. More stable, larger lift and extended flight time.
I have used both Dt750 and Sunnysky and the later ones are much smoother than the DT750s. If you want FPV then go for sunnysky.

what about Turnigy Multistar 2216-800Kv 14Pole Multi-Rotor Outrunner. Is that good compared with sunny sky ? Not able to find low kv sunny sky motors.

Well for these kind of motors you have to look into the international websites. Very rarely you will find them in domestic stores. Even multistars are good brand. Have good reviews over the internet. But I have never used them so i can't comment.

It is available in vibrant hobbies @Rs. 1428

You can try it but before that go through the datasheet and feedback of the motor over the net. Also you can use emax lower kv motors. They are available in some of the LHS. They are also good.

If you're buying motors from international sites avoid HK as motor QC is crap....if you want to buy motors from HK only get turnigy XP motors as it has best QC...buy from rctimer,banggood,etc

@subbiya sir,
Gave away 3 DT750s to a fellow member in Chennai for 600 each without realising the current price.
But no regrets, hope he found them useful.
I mention this because i tested them before despatching.

On an 11x5.5 EMP prop, they gave 700gms thrust at 110watts (9amps on 3s)

Satyagupta Sir said he got 1100gms thrust at 18amp.

So these DT 700-750s are most effective at low rpm on large props. If you search the net, you'll find the test that found a 12x3.8 as the most efficient for this motor.
Hope you find this data useful.
(I must confess not knowing anything about the other motor mentioned...)
Regards.

Not able to find any reviews/datasheet about Turnigy Multistar 2216-800Kv.

I saw some emax low kv motors, but it looks like not efficient.

Please suggest me low kv motor and where can I buy it.
Where can I buy SunnySky motors in India?

Subbiya, im the lucky one kk sir mentioned. And I have to mention that he never asked any money, but its me who forced him to get that 600rs per motor.

As far as the motor, I cud say they are so smooth, and efficient, but they are on the heavy side, so if you are going for a 450 size, go with something like mystery 1000kv motors, these dt750motors require 12inch props and will be overkill for smaller quads,

They are best suited for tricopters where you need more thrust per motors,
thanks iyer sir, now those motors are in my tricopters going fine till now.

Ashok. P

@subbiya
sunnysky 2216 @ quadkopters
http://www.quadkopters.com/product/brushless-motors/sunnysky-2216-11-900kv/

sunnysky 2212 @rcmumbai
http://rcmumbai.com/index.php/product/sunnysky-x2212-kv980-brushless-motor/