HK-4225-550 Scorpion 4225-550 Limited Edition Brushless Motor (6mm Shaft)The Scorpion HKII-4225-550 Limited Edition motor was developed for use in 600 class helicopters running on 12-cell Li-Po power. This motor represents the most technologically advanced power source ever offered for a 600 class electric helicopter. Each new HKII-4225 Limited Edition motor is wound with a single strand of 15 AWG (1.4mm) wire for the highest possible efficiency. This motor is capable of running continuously at an input power of 3550 watts at 80 amps, and can handle peak inputs of 5770 watts and 130 amps for 5 second bursts.Scorpion Competition 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 rated for operation at 200 degrees C (392 F), making a motor that is virtually impossible to burn up in normal use.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.SpecificationsStator Diameter............................ 42 mm (1.65 in)Stator Thickness........................... 25 mm (0.98 in)No. of Stator Arms............................................ 12No. of Stator Poles............................................ 10Motor Wind....................................... 11 Turn DeltaMotor Wire................................. 1-Strand 1.35 mmMotor Kv........................................... 550 RPM/VoltNo-Load Current (Io/10V)...................... 2.33 AmpsMotor Resistance (RM)......................... 0.016 OhmsMax Continuous Current........................... 80 AmpsMax Continuous Power.......................... 3550 WattsWeight................................. 393 Grams (13.77 oz)Outside Diameter........................ 52.3 mm (2.06 in)Shaft Diameter........................... 5.98 mm (0.24 in)Body Length.............................. 51.50 mm (2.03 in)Overall Shaft Length.................... 91.5 mm (3.60 in)Max Lipo Cell................................................... 12sMax Peak Current................. 130 Amps (5 seconds)Max Peak Power.................. 5770 Watts (5 seconds)Motor Timing.................................................. 5degDrive Frequency............................................. 8kHz