Transmission having plural clutches

A transmission having a plurality of clutches (C1, C2) includes a first clutch (C1) for connecting and disconnecting transmission of driving force to a first input shaft (31) including a driving gear (G1, G3, G5) configured to be engaged with a driven gear provided at an output shaft (41) of the transmission driven by a driving force generating means, a second clutch (C2) operating independently from the first clutch, the second clutch for connecting and disconnecting transmission of driving force to a second input shaft (32) including a driving gear (G2, G4) configured to be engaged with a driven gear provided at the output shaft of the transmission driven by the driving force generating means, a driving force detection means (51, 52) for detecting driving force, a slip detection means (62) for detecting physical quantity related to a slip of driving wheels; characterized in that the transmission having the plural clutches includes a means for controlling the second clutch (71) for importing detected result of the physical quantity related to the slip and the driving force and for controlling engagement ratio of the second clutch where the first clutch is engaged.