2-speed Hydraulic Variable Displacement BD1 BD2 BD3 BD5 BD6 SAI BD motor

Displacements Available:  6.1 to 112.7 cu.-in./rev. (full displacement)

Max-Min Displacement Ratio from 1.2 to 6:1

Maximum Speed  3500 rpm

Peak Power:  322 hp

Crankshaft design

94% Starting and running torque

99% Volumetric efficiency

Sai BD Series Dual Displacement Motor is also based off the GM Series but incorporates the innovative central bearing.

The shift from one displacement to the other is achieved by pilot pressure acting on a crank shaft eccentric. This ensures a smooth transition when shifting from one speed to the other.

BD Series also tolerate freewheeling in full cavitation as with other models. If run as a pump they can also reach full speed in low displacement. 
The motors are capable of working at low speeds with a high degree of speed stability.
Output torque remains constant and does not fall away at very low speeds, on start up or in stall conditions. BD2 offers 100% to 50 % speed change ratio while BD1 offers 100 % to 25%.

The BD series of products consists of items that are available in sizes from 1 to 6, being characterized by slide bearings and an extremely low friction coefficient. The very high starting torque efficiency and the mechanical efficiencies that are higher than average are other important features worth mentioning, and are applicable in both low and high displacement models. The motors are capable of working at low speeds with a high degree of speed stability, with the minimum stable speed depending on the motor displacement.