Continuously variable transmission

A belt continuously variable transmission comprising:

• a variator having a belt wound around a pair of pulleys;
• and
• a transmission case including a container chamber for the variator, wherein
• a desired speed ratio is achieved with a winding radius of the belt changed on each of the pair of pulleys,
• the container chamber includes a circumference wall portion surrounding an outer circumference of the variator,
• the pair of pulleys are provided to be rotatable about a pair of rotation axes that are set to be parallel to each other while being separated from each other, inside the circumference wall portion,
• each of the pair of the pulleys includes a fixed pulley and a movable pulley that is displaceable in a direction along the rotation axes, and is configured to have the winding radius of the belt on the pulley changed in accordance with a displacement of the movable pulley in the direction along the rotation axes,
• the belt includes elements stacked to be arranged in an annular form;
• and rings binding the elements stacked,
• the elements each include flank faces held by the fixed pulley and the movable pulley, on both sides in a width direction, and
• the circumference wall portion is provided with a monitoring hole enabling the flank faces to be monitored.