Hobbywing XeRun AXE 4987 R3S Sensored FOC Brushless Motor for RC Crawlers

FOC stands for Field-Oriented Control, an advanced motor control algorithm that precisely manages the magnetic field in the motor to deliver smooth, linear torque at all speeds — including extremely low RPM. For RC crawling, this eliminates the cogging (jerky, stuttering movement) that is common with standard sensored or sensorless brushless motors at slow speeds. The result is ultra-smooth, precise throttle control when picking your way over rocks and technical terrain, giving you the same feel as a high-quality brushed motor but with the power and efficiency of a brushless system. The AXE 4987 R3S also uses a high-precision magnetic encoder that provides 60x better position accuracy than standard Hall sensors, further enhancing low-speed smoothness.

The AXE 4987 R3S is designed for 1/5 and 1/6 scale RC crawlers and trail trucks. Its 49.5mm diameter and 87mm length fit platforms including the Axial 1/6 SCX6, Losi 1/6 Super Baja Rey, Losi 1/6 Super Rock Rey, Traxxas TRX-6, and other large-scale crawlers that use a 1/5 or 1/6 scale motor mount. Always verify your chassis motor bay dimensions before ordering. The motor uses a standard 8mm shaft.

The motor-only variant ($117.99) includes just the AXE 4987 R3S motor and sensor cable — ideal if you already own a compatible Hobbywing AXE R3 FOC ESC or are upgrading from a previous motor. The R3 ESC + 4987 R3S Motor combo ($269.99) includes both the motor and the Hobbywing AXE R3 FOC ESC, which is specifically designed to work with the AXE motor series and enables full FOC functionality. If you do not already own a compatible FOC ESC, the combo is the recommended choice to ensure full compatibility and optimal performance.

The AXE 4987 R3S is designed to work optimally with Hobbywing's AXE series FOC ESCs (such as the AXE R3 included in the combo). While the motor can physically connect to other sensored brushless ESCs, full FOC functionality — including the smooth low-speed cogging-free control — requires a compatible FOC ESC. Using a standard sensored ESC will work but will not deliver the FOC performance advantage. For the best crawling experience, we strongly recommend pairing with the Hobbywing AXE R3 ESC.

IP66 means the motor is fully protected against dust ingress and powerful water jets from any direction. In practical RC use, this means you can drive through mud, puddles, rain, and stream crossings without damaging the motor. Note that IP66 does not cover full submersion (that would require IP67 or higher), so avoid prolonged underwater operation. For most crawling and trail running scenarios including wet rocks, mud pits, and rain, IP66 provides excellent protection.