Twin-clutch transmission

A twin-clutch transmission comprising:

• a first input shaft (14) for transmitting driving force from an engine via a first clutch (12);
• a second input shaft (18) for transmitting driving force from the engine via a second clutch (16);
• a first output shaft (20), a second output shaft (22), and a sub shaft (24) disposed parallel with the first input shaft and the second input shaft;
• a pair of first speed input and output gears (26a, 26b) provided between the first input shaft and the first output shaft;
• a pair of fourth speed input and output gears (30a, 30b) provided between the second input shaft and the first output shaft;
• a pair of third speed input and output gears (34a, 34b) and a pair of fifth speed input and output gears (36a, 36b) provided between the first input shaft and the second output shaft;
• a pair of second speed input and output gears (40a, 40b) and a pair of sixth speed input and output gears (30a, 42b) provided between the second input shaft and the second output shaft;
• a backward output gear (46b) provided on the first output shaft;
• and
• idler gears (46c, 46d) provided on the sub shaft,
• wherein the third input near is integrated with the first input shaft, and
• wherein the idler gears connect the third input gear and the backward output gear to each other.