Not every Ferris mower will track perfectly straight when both sticks are pushed all of the way forward. There are several variables that will play into the way the mower will track when the sticks are in the full forward position. The tires for example will make a difference if the circumference and air pressures are not matched up properly. You can have a matched set of tires that have a 1/4” difference in circumference. These tires are considered a set, but will roll farther a ¼” per complete tire roll. The air pressure can also add or subtract the way a tire will roll by changing the circumference. When you set your air pressures, it may be necessary to have one tire set at one setting and the other at 2 +/- psi to even them out. Also the stops may be set where some adjustment may be needed. Refer to your operators manual for adjustment directions. It is also possible the hydro adjustment is off, but do not change this as it may allow the mower to move without control. If you still find that the sticks are off then you may want to have your local dealer go through and reset the adjustments.