A rotary sprinkler system for both above-the ground and pop-up rotary sprinkler systems that controls the rate of nozzle rotation is disclosed. To maintain a relatively constant and controlled nozzle rotation, one or more chamfered spokes are included on the turbine of the sprinkler system. This turbine configuration together with a stator assembly that regulates fluid flow to the turbine control nozzle rotation despite variations in fluid flow. In particular, the chamfered spokes counteract the spin of the turbine in direct relation to the amount of water that bypasses the driving blades of the turbine.