This one concerns ride on mowers. Spray a good quality (i.e. one that dries real thick) chain lube on the hinge points of the mowing deck linkages. Chain lube is good because it penetrates easily and then dries like grease. Use it on the pedal hinge points and chain drives as well. It is best applied after water blasting and drying the mower. This makes it easier to see what you are doing and gets rid of the dirt so the oil can penetrate better. Afterwards your rider will have that just serviced feel where everything works smoother and quieter. How often should you do this? as often as you like. Be sure not to get the oil on the drive belts.