Patent ID: 7210367

Claim:
A twin-clutch transmission, comprising: an input shaft; an output shaft disposed coaxially with said input shaft; a cylindrical first countershaft disposed in parallel to said output shaft; a second countershaft disposed so as to inserted into said cylindrical first countershaft; a plurality of gear sets disposed between said output shaft and said first and second countershafts; a first clutch mechanism operative to transmit a drive power to said first countershaft; a second clutch mechanism operative to transmit the drive power to said second countershaft, wherein said first countershaft is supported on a casing of the transmission via a bearing, a counter gear for a forward lowermost speed ratio among said gear sets is carried by the first countershaft, said first countershaft includes a projecting portion at an end thereof which extends in a shaft axial direction, a gear carried by said second countershaft includes a recess portion which is formed at a side face thereof, said projecting portion of the first countershaft extends into said recess portion of the second countershaft in such a manner that said projecting portion of the first countershaft is overlapped with said gear on the second countershaft in the shaft axial direction, and said first countershaft is supported on said casing via a first bearing and said gear on the second countershaft is supported on said projecting portion of the first countershaft via a second bearing.