The present invention is capable of suppressing gear shift shocks or delays in acceleration with no interruption of driving force and reducing the weight. Disclosed is a transmission which is provided with multiple stage shift gears so arranged to shift a number of dog clutches to shift a gear to the upper stage of the multiple stage shift gears, and is characterized in that a guide part is provided to a shift operation section and the dog clutches on each of the sages so as to move the lower dog clutch in a neutral direction by a coasting torque acting on the lower stage by a shift rotation of the upper stage to release a meshing engagement when meshing engagements of the lower and upper dog clutches are simultaneously performed by an operation of the shift operation section.

A transmission system (8) comprising at least one floating gear (14a, 16a, 18a) rotationally mounted upon a first shaft the system comprising a floating gear activation system for controlling torque transfer between the at least one floating gear (14a, 16a, 18a) and the first shaft (10), the gear activation system comprising a first device (28, 30) having a friction interface (28) for frictional engagement with a friction interface (30) disposed on a first side of the at least one floating gear (18a), and a second device (25, 26) having a locking interface (25) for an interpositional engagement with a locking interface (26) disposed on a second side, opposing the first side, of the at least one floating gear (18a), whereby the floating gear (18a) is rotationally coupleable to the first shaft (10) by the friction interface (28/30) and/or the locking interface (25/26).