KO tech is the very first motor company to incorporate a cooling system to  RC brusless motors that does not rely on fans or fin style designs . 

The traditional fan or fin styled design calls for a fan machined in to the bell (on the inside, or outside of the bell, this method has 2 major flaws).

Firstly this design is" handed " meaning cw rotating motors must have a fan design orientated differently to a ccw rotating motor if the fan is to be effective. Secondly a fan or fan shaped spokes design robs the motor of power to drive the fan and in turn lowering response times, ultimate RPM and ultimate available torque.

KO Technologies has developed ACPC to compress oncoming air directly at the bell spoke face, forcing the air past the spokes and directly into the stator and magnet assembly.

This lowers operating temps, increases torque and dramatically increase response times all the way along the rpm  range. As a bonus the angled ring that forms the ACPC design is used as a counter balance used to reduce the amount of putty used to balance a motor bell.

Specification

• Magnet: 50SH
• Bearing: EZO 9x4x4
• Stator Laminate: 0.15 nikkon Japanese Steel
• Shaft: Hollow Titanium
• Weight: 35g
• Stator Size: 2208
• Shaft Retainer: 2mm Hex Screw 
• KV: 2540
• Number of cells.(Lipo): 4-6s 
• Wire Length: 145mm
• Wire AWG: 18AWG
• Bell Material: 7075 Alu
• Base Material: 7075 Alu
• Bolt Pattern: 16x16mm
• Windings: 180d High temp 99.9% Pure Copper 
• Cooling: Active choke point compression technology (ACPC)
• Prop Seat: CNC knurling (Anti-slip)
• Bell / Top Cap Connection Assembly: High Strength Dual Rebate Design
• Winding QC: Individually Tested to 500volt @ low amps 
• Balancing QC: Individual dual stage dynamic balance test for each bell