Greg Thomas, I'd start off with this:"GROUND SPEED CONTROL LEVER ADJUSTMENT
The control levers have three adjustments:
To Adjust Control Lever Height: Pull the levers in across the operator's lap to their DRIVE positions. Loosen the mount bolts (D, Figure 32) and raise or lower the levers to the desired position. Tighten the mounting bolts.(D).
To Adjust Control Lever End Gap: The control lever end gap (C, Figure 33) should be adjusted so that the levers do not contact each other when placed in DRIVE positions. Loosen the jam nut (A, Figure 32) and adjust the length of the carriage bolt (B) so that the levers do not contact each other. Repeat on the opposite side. Tighten the jam nut (A) to lock the carriage bolt in position.
To Adjust Operator Clearance: The space between the operator and the control levers can be increase by removing the lower mounting bolt (D, Figure 32), pivoting the lever forward, and reinstalling the capscrew through the control lever and forward slot (C). Repeat with the other ground speed lever.
Figure 32 Control Lever Adjustment
SPEED BALANCING ADJUSTMENT
If the rider veers to the right or left when the ground speed control levers are in the maximum forward position, the top speed of the right lever can be balanced by turning the adjustment knob (E, Figure 32). Loosen the jam nut and turn the knob COUNTERCLOCKWISE
to increase speed or CLOCKWISE to decrease speed. Tighten the jam nut when complete.