The Scorpion HKIII-4025 motors follow in the footsteps of the larger
HKIII-4035 models which re-wrote the book on power for helicopter
models. Replacing the earlier model HK-4025-740, the HKIII-4025-730
motor features a new patented rotor can that provides several benefits.
First, it is thicker for more stability at higher speeds, and this also
helps to retain more of the magnetic field for higher efficiency.
Second, the outer surface of the rotor can features a new spiral rib
pattern that increases surface area and helps to move air around the
motor for increased cooling and lower operating temperatures.
In addition to the mechanical changes to these motors, changes in
metalurgy in the stator assembly and rotor can have increased the
overall efficiency. This allows the motor to handle higher currents
while developing more torque and more power that will allow your
helicopter to perform like never before.
Scorpion HKIII Series Brushless Motors are built from the best materials
available, and are designed to provide both quality and performance at
an affordable price. Scorpion starts with high quality aluminum alloy
parts that are produced on the latest CNC milling machines. These parts
are then gold Electro-plated to provide a beautiful, long-lasting
finish. The stators are made with 0.2mm laminations to give maximum
efficiency, and minimum Eddy current losses. The stators are epoxy
coated to prevent shorts, and are wound with wire that is rated at 180
degrees C (356 F). The magnets used in Scorpion Motors are the highest
temperature rating available, making a motor that is virtually
impossible to burn up in normal use.
All Scorpion HKIII-4025 series motors come with 4mm male Bullet style
connectors already attached, and include a hardware package that
contains 3 matching female Bullet connectors for your speed controller
with matching heat shink tubing. For maximum strength, the Scorpion
HKIII-4025 series motors feature an 8mm motor shaft that is ground down
to a 6mm diameter at the output end to fit standard size pinion gears.
Since the HKIII Series motors are primarily designed for Helicopter use,
they do not include a prop adapter. If you intend on running a prop on
this motor, you will need to purchase a prop adapter for a 6mm shaft.
Scorpion Motors are built to last, and are backed with a 2-Year warranty
against defects in materials or workmanship. However, due to the high
RPM of these motors, and the fact that we cannot control the
installation and setup, the bearings are not covered by the 2-Year
warranty, nor is any subsequent damage caused to the motor by a bearing
failure. Bearings are a normal wear item, and as such, need to be
maintained and changed periodically. For maximum life, make sure that a
sufficient gap is left between the pinion and main gear during motor
installation to avoid binding, and put a small drop of oil on each
bearing every 5-6 flights. It is the responsibility of the pilot to
ensure that the bearings are maintained properly.
The Scorpion Motor Bearing Lubrication Kit is now available for
maintaining the bearings in your helicopter motor. To view this
product, please check out the
Bearing Lubrication Kit.
For the best overall combination of quality, performance, and value, use Scorpion Motors in your helicopter!
Specifications
Stator Diameter ............................ 40.0 mm (1.575 in)
Stator Thickness ........................... 25.0 mm (0.984 in)
No. of Stator Arms ................................................ 12
No. of Magnet Poles ............................................... 10
Motor Wind .......................................... 4-5 Turn Delta
Motor Wire ..................... 21-Strand 0.29mm (29 AWG)
Motor Kv ............................................. 730 RPM / Volt
No-Load Current (Io) .................. 1.95 Amps @ 10 volts
Motor Resistance (Rm) ............................. 0.013 Ohms
Max Continuous Current ............................... 75 Amps
Max Continuous Power .............................. 2600 Watts
Peak Current (5 Seconds) ........................... 105 Amps
Peak Power (5 Seconds) ............................ 3500 Watts
Weight ...................................... 354 Grams (12.49 oz)
Outside Diameter .......................... 49.9 mm (1.964 in)
Shaft Diameter ............................. 5.98 mm (0.236 in)
Body Length ................................. 51.8 mm (2.039 in)
Overall Shaft Length ...................... 83.7 mm (3.295 in)
Max Li-Po Cell Count ............................................ 10s
Recommended Timing ................................ 5 Degrees
Recommended PWM Frequency .......................... 8 KHz