For bowed string players, the bow becomes a natural prolongation of the musician's arm, and its ability to be controlled is therefore really important. Appreciations like "it is quite light" or "the weight is not even" are common among violinists, and reveal differences between bows on the perceived weight at different bow-string contact points (frog, middle, tip). The present study aims at exploring how bow mass distribution influences its perceived weight and behaviour in different playing conditions. The mass distribution of a light violin bow built specifically for this project is changed by adding masses at different parts of its stick. The influence of mass distribution on the mechanical behaviour of the bow in a playing situation is explored, mainly through the variation of both center of gravity and moment of inertia. Then, different mass distributions on the same bow are tested by professional musicians, and some perceptual tests are conducted. Their evaluations will be correlated with the finger forces required to maintain a given force on the string and the bouncing frequency of the bow.