Self aligning crank assembly and method

A cycle transmission comprising:

• a crank assembly rotatably mounted on a cycle frame, said crank assembly having at least one chain ring, said chain ring being positioned in a parallel relation to a first plane and being moveable laterally with respect to said cycle frame, and wherein lateral movement of said chain ring occurs in a direction substantially perpendicular to said first plane;
• a freewheel cluster assembly having at least two freewheels, said freewheel cluster assembly being rotatably coupled to said cycle frame, the rotational plane of said freewheel cluster assembly being substantially parallel to the rotational plane of said crank assembly;
• and
• a drive chain coupling at least one of said freewheels to said at least one chain ring, whereby said drive chain transfers torque from said chain ring to said at least one freewheel, and whereby placement of the drive chain on said one of said freewheels maintains said chain ring in substantial lateral alignment with said at least one freewheel.

A bicycle comprising:

• a frame;
• a first wheel rotatably attached to said frame;
• a second wheel rotatably attached to said frame in substantial alignment with said first wheel;
• a transmission having:
• a crank assembly rotatably mounted on said frame, said crank assembly having at least one chain ring, said chain ring being positioned in a parallel relation to a first plane and being moveable laterally with respect to said frame, and wherein lateral movement of said chain ring occurs in a direction substantially perpendicular to said first plane;
• a freewheel cluster assembly having at least two freewheels, said freewheel cluster assembly being rotatably coupled to said frame, the rotational plane of said freewheel cluster assembly being substantially parallel to the rotational plane of said crank assembly;
• and
• a drive chain coupling at least one of said freewheels to said at least one chain ring, whereby said drive chain transfers torque from said chain ring to said at least one freewheel, and whereby placement of the drive chain on said one of said freewheels maintains said chain ring in substantial lateral alignment with said at least one freewheel.

A method of operating a bicycle transmission having a crank assembly with at least one laterally moveable chain ring and a freewheel cluster having at least a first and second freewheel, said method comprising:

• providing a drive chain coupling said at least one chain ring to said first freewheel;
• providing a mechanism for shifting said drive chain between said at least first and second freewheels;
• rotating said crank assembly and chain ring;
• shifting said drive chain from said first freewheel to said second freewheel, wherein said shifting induces a lateral movement in said chain ring to bring said chain ring into substantial lateral alignment with said second freewheel.

A cycle transmission comprising:

• a crank assembly rotatably mounted on a cycle frame, said assembly having at least one chain ring, said chain ring being moveable laterally with respect to said cycle frame;
• a cassette assembly having at least two freewheels, said cassette assembly being rotatably coupled to said cycle frame, the rotational plane of said cassette assembly being in substantial alignment with the rotational plane of said crank assembly;
• and
• a drive chain coupling at least one of said freewheels to said at least one chain ring, whereby said drive chain transfers torque from said chain ring to said at least one freewheel, and whereby placement of the drive chain on said one of said freewheels maintains said chain ring in substantial lateral alignment with said at least one freewheel.