This paper describes the experimental determination of performance and torque characteristics of the Jober commercial low-solidity, fast-running wind rotor for direct driven wind-pumping applications. A scale model of the Jober wind rotor is tested at different blade setting angles to determine the best configuration. The optimal configuration lies within a range of blade pitch angles between 45° and 30°. The performance of the rotor is also compared to a newly designed, more aerodynamic rotor based on the theory of wind rotors. It is shown that an aerodynamic design for the rotor can be used in water pumping applications, which shows improved performance when compared to the original commercial design. The overall wind-to-water conversion efficiency is analyzed theoretically and the results show that there is a substantial improvement in the newly designed rotor configuration as compared to the actual configuration of the Jober windpump.