Some quick research and a process of ellimination tells me this...
Because it's a model 101 and not 100, it does indeed have flow control, and the flow control knob is in the center of the valve. It has standard rh threads, so turning it clock wise should close off the flow path and therefore decrease the flow, while ccw will open the path and increase the water flow.
As with all valves like these, the valve is turned on/off manually by turning the selinoid... the 'tube' with the wires sticking out of it. When used with a controller, the selinoid lifts the diaphram a little to allow the valve to open. You accomplish the same thing manually by slightly unscrewing the whole selioid.
So by process of ellimination, the smaller knob is the bleeder.