The Spektrum RC Firma 4-pole Brushless Motor, is a great choice for 1/10 Scale 4WD models looking for a high RPM motor upgrade running up to 3S (12.6v) power. Featuring a low cog 4-pole rotor design, CNC machined aluminum housing, insulated high purity copper windings, high-quality alloy steel 5mm output shaft and high-precision bearings for high durability and smooth rotation. Preinstalled 4mm bullet connectors are used for ease of use and instillation.Â
NOTE:Â Only compatible with the 85A Firma ESC (sold separately) when run on 2S power.
Features:Â
- Perfect upgrade for 540 and 550 size brushed motors with the same shaft diameter and mounting patternÂ
- Perfectly matched for the Firma 130 Smart ESC (sold separately)
- High-quality 4-pole sintered rotors
- Includes 4mm gold plated bullet connectors
- Precision ball bearings and hardened steel 5mm shaft
- SafeD-5 Pinion compatible
Specifications:
Application: 1/10 Scale Surface
Input Voltage: 12.6V
RPM/Volt (Kv):Â 3900Kv
RPM/Volt (Kv):Â 3900Kv
Maximum Continuous Current: 45A
Motor Type: Brushless
Outer Diameter: 1.4″ (36 mm)
Product Length:Â 2.35″ (60 mm)
Shaft Diameter:Â 0.2″ (5 mm)
Includes:Â
Includes:Â
- (1) Spektrum Firma 3900kv Sensorless Brushless Motor
- (1) Product Manual
This product was added to our catalog on October 21, 2021























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