Since 2010 when the Scorpion HKIII-45 series is released, Scorpion has received a lot of feedback by World Champions, pilots and enthusiasts in all facets of the hobby praising Scorpion's performance as the gold standard in R/C model power. 

The HKIII-4025 series motors have proven themselves to be extremely successful in the helicopter community and became the most popular motor used in the 550-570-600 class helicopters worldwide.

And now, we are pleased to announce the release of the 4th generation HKIV-4025 series motors.  With the same motor design and material of HKII-45 series, and single strand winding technique on this size of motor, the new HKIV-40 has a better efficiency and power conversion than the previous HKIII-40 series, with an entirely new EM field design, while improving the compatibility with various speed controllers available on the market.  The new design motor will deliver even more power to your helicopter, with increased efficiency!

Stator Diameter: 40.0mm (1.57 in.)

Stator Thickness: 20.0mm (0.79 in.)

No. of Stator Arms: 12

Magnet Poles: 10

Motor Wind: 3+3 Turn Delta

Motor Wire: 1-Strand 1.7mm

Motor KV: 1100Kv RPM/Volt

No-Load Current (IO/10V): 5.29 Amps

Motor Resistance (Rm): 0.006 Ohms

Max Continuous Current: 100 Amps

Max Continuous Power: 2220 Watts

Weight: 347 Grams (10.58 oz.)

Outside Diameter: 49.50mm (1.95 in.)

Shaft Diameter: 5.98mm (0.24 in.)

Body Length: 54mm (2.13 in.)

Overall Shaft Length: 89.9mm (3.54 in.)

Max Lipo Cells: 6S

Max Peak Current: 130A (5 seconds)

Max Peak Power: 2886 Watts (5 seconds)

Motor Timing: 5 degrees

Drive Frequency: 8kHz