Hello everybody,

I am planing on building my first quadcopter, for the same I am considering:

http://www.ebay.in/itm/Quadcopter-F450-Kit-4xBLDC-1000KV-Motor-4x-30A-Motor-Controller-4x-Propellor-/121978742900?hash=item1c667fe874:g:ReAAAOSwLs5XLNy2
(OR)
http://www.ebay.in/itm/1400KV-Brushless-Motor-30A-ESC-1045-Propeller-Set-/121983640287?hash=item1c66caa2df:g:UvsAAOSwyjBW4wlb (X4)

Can you please help me out in choosing the KV rating of the motors, the frame I will build myself. The battery i will be using is a 1250mah, 20c at 11.1 V, I have 2 of these

1) Is it possible that if i balance charge all the cells to the exact same voltage that i can hook them up in parallel using a "Y" connector cable to help spread the batteries weight across the frame and also increase the flight time? (I am thinking that the output after paralleling them will be; voltage=11.1v and current=1250+1250=2500mah is this correct?)

2)What is the difference between using 1400KV and 1000KV motors?

3)What will be the difference in the flight times?

4)What is the most efficient combination of the above mentioned motors and props?

Any help is much appreciated.

(I apologize if there are any obvious or stupid questions i am just starting to build multi rotors)

1) I cant understand how you are gonna charge two cells of lipo parallel in single pack. If you think to charge all cells in lipo pack using parallel method then you may short the battery. google for cells connection internally.you will understand.
2) kV means rpm/volt at no load theoretical. 1400kv motor supplied with 11v runs at 11*1400=15400rpm no load and full throttle. Both of them are good depending on usage. High kV is better for racings and have good thrust sometimes but low efficiency whereas low kV are efficient and are slightly sluggish can be used for photography.
3) flight times depends on batteries and motors, ESC efficiency and how you play with them.
4) Available by manufacturers itself and can be found on google and it varies from motor size also.

1) You can do something like this --
Rest have been answered above