In order to characterize the power transmitting state of a continuously variable transmission (CVT) using metal V-belts, mean coefficients of friction between blocks and pulleys, and between the blocks and rings, are introduced. The present approach is primarily based on the classical Euler’s equation for conventional V-belts. The existence of idle and active arcs is taken into consideration by adjusting the coefficients of friction, since the power is assumed to be transmitted through all the contact arcs of the belt in this study. The power transmitting mechanisms induced by the estimated mean coefficients of friction are highly consistent with the data measured by the sensors made by blocks. The mean coefficients of friction also have some universal trends with respect to transmitted power, torque ratio, speed ratio and so On. The mean coefficients of friction would be applicable not only for characterizing the power transmitting state, but also for designing a CVT using metal V-belts.