Cobra C-4120/12 Brushless Motor, Kv=850

Cobra Brushless Motors offer performance and value for Sport Flyers and Competition pilots alike. They are built from high quality components, and are designed to give years of top-level performance. All Cobra Motors are shipped in a custom designed package that features protective foam on all six sides of the box, with 3 separate compartments to protect the motor, accessory pack and cross mount.

The Cobra 4120 series motors have a 6.0mm shaft for extra strength, as well as oversize ball bearings to support the shaft and provide a long life. There are two internal bearing measure 12mm x 6mm x 4mm and the outer bearing measures a massive 17mm x 6mm x 6mm! The stators are made with 0.20mm laminations for maximum efficiency and minimum Eddy Current losses. Also included on the motor are ultra-flexible motor leads with high-temp silicone rubber insulation and 4.0mm bullet connectors already installed.

Included with every Cobra 4120 Series Motor is a complete accessory package which contains the following items:

● Heavy Duty 4mm Thick Cross Style Motor Mount
● Four M4x8mm Motor Mount Screws
● Bolt-On style threaded prop adapter with 8mm shaft and M8x1.25mm thread
● 4 Prop Adapter retaining screws
● Three female 4.0mm bullet connectors
● Three pieces of heat-shrink tubing
 

Click here for the Cobra C-4120/12 Propeller Data Chart

Cobra 4120/12 Motor Specifications
Stator Diameter	41.0 mm (1.614 in)
Stator Thickness	20.0 mm (0.787 in)
Number of Stator Slots	12
Number of Magnet Poles	14
Motor Wind	12 Turn Delta
Motor Kv Value	850 RPM per Volt
No Load Current (Io)	2.74 Amps @ 14 Volts
Motor Resistance (Rm) per Phase	0.021 Ohms
Motor Resistance (Rm) Phase to Phase	0.014 Ohms
Maximum Continuous Current	75 Amps
Max Continuous Power (3-cell Li-Po)	830 Watts
Max Continuous Power (4-cell Li-Po)	1110 Watts
Max Continuous Power (5-cell Li-Po)	1390 Watts
Motor Weight	293 grams (10.34 oz.)
Outside Diameter	49.8 mm (1.961 in.)
Shaft Diameter	6.00 mm (0.236 in.)
Motor Body Length	51.8 mm (2.039 in.)
Overall Shaft Length	74.5 mm (2.933 in.)
Motor Timing	5-10 degrees
PWM Frequency	8 KHz