Turnigy Aerodrive SK3 - 4240-740kv Brushless Outrunner Motor 

Turnigy SK3 Motors are the next leap forward in motor quality and design. 

Turnigy says:

We instructed the engineers to source the best quality magnets, bearings and materials available to them and develop a motor that would not only rival, but surpass the quality of many leading motor manufactures on the market today. The result is an efficient, high caliber motor using quality double shielded bearings, sintered Neodymium magnets and a string wound stator ensuring an accurate and consistent winding each and every time. The Turnigy SK3 motors are suited to modelers who are seeking a quality brushless motor without compromise. 

Specs:

Turns: 10T

Voltage: 4~5S Lipoly

RPM/V: 740kv

Internal resistance: 0.013 OhmMax

Loading: 50AMax

Power: 870W

Shaft Dia: 5.0mm

Bolt holes: 25mm

Bolt thread: M3

Weight: 195g

Motor Plug: 3.5mm Bullet Connector