The brake adjustment is a real pain. Tilt the seat and you will see that the linkage pulls up on arms mounted on the wheel motors.When the brake pads wear the arms run out of travel. You need to loosen the arm that is on the wheel motor, and slide the arm off the splined shaft. Rotate the shaft in the same direction as the linkage pulls to apply brakes, then slide the arm back on. Basically you "jumped" the shaft on the splined arm. If that doesn't work you will have to pull the sidecover case and look at the pads/mechanism in the chain case.