It is of great importance to improve the accuracy of the diverter to achieve high accuracy liquid flow measurements by using static gravimetric systems with flying start and finish. A new system with the double diverting wing has been developed in order to reduce the diversion timing error that dominates the uncertainty for the calibration of flowmeters. The diversion timing error has been estimated with a small prototype in a water flow circuit in order to make a comparison between the performance of the new system and those of previous system with the single diverting wing. The results show that the jet flow condition has little effect on the timing error estimated by the double wing method, although the error with the single wing is dependent on the liquid flow rate. Therefore, the triggering of the timing system can be easily adjusted over a wide range of flow rate by using the new diverter system.