Blue Bird BMS-125WV Servo - 6.2Kg.cm 0.09s 11.3g 10mm

The Blue Bird BMS-125WV is the highest torque servo in the new Blue Bird BMS-125WV/126WV/127WV range of 11g servos. At 8.4V the BMS-125WV's torque is a massive 6.2 kg.cm. The speed is slightly compromised but is still 0.09 seconds per 60° of movement. It is suitable for all control surfaces on ligher F5J models and most gliders up to 4 m wingspan. At 10 mm thick it is suitable for mounting in small fuselages and thin wings and tails.

The WV in the name stands for Wide Voltage, indicating that this servo has wide range of acceptable supply voltages and is suitable for 1S LiPo, 4 or 5 cell NiMH and 2S LiPo operation.

The Blue Bird BMS-125HV is a great servo built to the same space saving form factor as the MKS DS6100 and MKS HV6100. It is similarly precise, with no free play in the geartrain, and it is much more powerful and faster than the competing products. The large output spline is identical to Futaba 25 tooth splines, so replacement output arms are readily available. Note the output spline is not the same as MKS so the servo cannot be used with most MKS accesories.

Although it looks like the BMS-105HV the BMS-125 WV uses new components and an improved internal design and does not suffer the longevity problems that affected some high hours BMS-105 installations.

Blue Bird BMS-125WV Specifications
Body dimensions	23.2 mm wide x 10.0 mm thick x 23.0 mm high	0.91" wide x 0.39" thick x 0.91" high
Max dimensions	32.0 mm wide x 10.0 mm thick x 25.0 mm high	1.26" wide x 0.39" thick x 0.98" high
Stall torque (3.7V)	2.7 Kg.cm	37 oz.in
Stall torque (6V)	4.3 Kg.cm	60 oz.in
Stall torque (8.4V)	6.2 Kg.cm	86 oz.in
Weight	11.3 g	0.40 oz
Lead length	16 cm	6.3 in
Operating speed (3.7V)	0.2 sec/60°
Operating speed (6V)	0.13 sec/60°
Operating speed (8.4V)	0.09 sec/60°
Operating voltage	3.5V to 8.4V
Operating temperature	0 to 40 °C
Bearings	Plain
Gear material	Metal alloy
Case material	Nylon
Motor type	Coreless DC motor
Working frequency	250 Hz
Dead band/resolution	2 µs
Pulse width for ± 60º	(L) 900 µs - (0°) 1520 µs- (R) 2100 µs
Digital	Yes
Programmable	No
Position feedback	Potentiometer
Supplied accessories	2 plastic output arms, 1 arm retaining screw, 4 mounting screws, Blue Bird sticker
Optional accessories	Ply Frame for Blue Bird BMS-125WV