Power transmission system and method of assembling the same

A power transmission system including a first power transmission member and a second power transmission member configured to be assembled together by spline-engagement, comprising:

• a biasing member including:
• a spring part elastically displaceable in a rotational direction;
• a locked part provided on a first end side of the spring part and configured to be locked by the first power transmission member;
• and
• a spline part provided on a second end side of the spring part,
• the biasing member being configured to bias the second power transmission member toward a first rotational-direction side with respect to the first power transmission member by the spline part of the biasing member being engaged with a spline part of the second power transmission member while the biasing member is disposed on a first axial side of the first power transmission member and locked by the first power transmission member, and the spring part is in a first elastically displaced state;
• and
• a temporarily fixing member disposed on the first axial side of the biasing member and having a temporarily fixing part configured to temporarily fix the biasing member to the first power transmission member in a second elastically displaced state where the spring part is elastically displaced more than in the first elastically displaced state,
• wherein the second power transmission member is provided, on the first axial side of the spline part, with a canceling part configured to, when the spline part of the second power transmission member is spline-engaged with a spline part of the first power transmission member through the spline part of the biasing member from the first axial side of the temporarily fixing member, cancel the temporary fixing of the biasing member to the first power transmission member by the temporarily fixing part so that the second power transmission member is biased toward the first rotational-direction side with respect to the first power transmission member while the spline part of the biasing member is engaged with the spline part of the second power transmission member in the first elastically displaced state of the spring part,
• wherein the biasing member further includes an inner annular part provided at a radial inside, an outer annular part provided at a radial outside, and a temporarily fixed part configured to be temporarily fixed by the temporarily fixing part,
• wherein the locked part is connected to the outer annular part,
• wherein the spline part of the biasing member and the temporarily fixed part are connected to the inner annular part, and
• wherein the spring part is connected at one end to the outer annular part, and at the other end to the inner annular part, and the spring part is elastically displaced in the rotational direction by the inner annular part being moved toward a second rotational-direction side with respect to the outer annular part.