Abstract: A golf club includes a reinforcing member installed on an inner circumferential surface of a shaft near a tip-side end portion and extends in an axial direction of the shaft to straddle an upper end of a cylindrical portion. The reinforcing member has a cylindrical shape configured by laminating prepregs obtained by impregnating carbon fibers being reinforcing fibers with a matrix resin. The reinforcing member is provided with: a first bias layer located at the innermost side in a radial direction; a second bias layer laminated on an outer side of the first bias layer (16A) in the radial direction, an orientation direction of the reinforcing fibers having an opposite direction to the first bias layer; and a straight layer laminated on the outer side of the second bias layer in the radial direction, an orientation direction of the reinforcing fibers being parallel to the axial direction of the shaft.

Abstract: A golf club includes a reinforcing member installed on an inner circumferential surface of a shaft near a tip-side end portion and extends in an axial direction of the shaft to straddle an upper end of a cylindrical portion. The reinforcing member has a cylindrical shape configured by laminating prepregs obtained by impregnating carbon fibers being reinforcing fibers with a matrix resin. The reinforcing member is provided with: a first bias layer located at the innermost side in a radial direction; a second bias layer laminated on an outer side of the first bias layer (16A) in the radial direction, an orientation direction of the reinforcing fibers having an opposite direction to the first bias layer; and a straight layer laminated on the outer side of the second bias layer in the radial direction, an orientation direction of the reinforcing fibers being parallel to the axial direction of the shaft.

Abstract: A golf club selecting method includes measuring a behavior of a golf club during a golf swing performed with the golf club gripped and selecting a golf club in accordance with the golf swing. At first, a swing information for characterizing the behavior of the gold club during the golf swing performed with the golf club gripped is acquired. Then a golf club is selected in accordance with the golf swing based on the acquired swing information, wherein the acquired swing information contains a movement speed at each of a plurality of predetermined positions which are different from each other on a golf club shaft axis of the golf club, and the movement speed is a speed in an impact state immediately before a golf ball is hit with the golf club.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency per unit time, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency per unit time, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: A golf club selecting method includes of measuring a behavior of a golf club during a golf swing performed with the golf club gripped and selecting a golf club in accordance with the golf swing. At first, a swing information for characterizing the behavior of the golf club during the golf swing performed with the golf club gripped is acquired. Then a golf club is selected in accordance with the golf swing based on the acquired swing information, wherein the acquired swing information contains a movement speed at each of a plurality of predetermined positions which are different from each other on a golf club shaft axis of the golf club, and the movement speed is a speed in an impact state immediately before a golf ball is hit with the golf club.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency per unit time, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency per unit time, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency per unit time, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency per unit time, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: An optimal golf club shaft for a golfer is selected from among various golf club shafts, the following. At first, a head speed of a golf club at a point when the golf club strikes a golf ball during a golf swing and a downswing time amount from a top point in time when a downswing begins during the golf swing until a golf ball striking point in time are detected. Then a golf club shaft stiffness suited to the golf swing by using the head speed at the time the golf ball is struck and the downswing time amount is computed. Finally, a golf club shaft having the computed golf club shaft stiffness is selected. The golf club shaft stiffness is computed such that the optimal golf club shaft becomes stiffer as the head speed becomes higher and/or as the downswing time amount becomes longer.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency per unit time, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency per unit time, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency per unit time, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency per unit time, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: Disclosed is a golf club set having harmonized golf club performance among the club numbers. In the golf club set, for at least three golf clubs, a ratio or a sum of a frequency per unit time, the frequency being measured by vibrating a tip portion of a golf club shaft constituting each of the golf clubs, and a frequency per unit time, the frequency being measured by vibrating a rear end portion of the golf club shaft, is determined in relation with order of the club number.

Abstract: Disclosed is an evaluation method of a golf club, where a rear end portion of a club shaft is vibrated in a state where a tip portion of the club shaft is fastened to measure a frequency per unit time, and a golf club using the club shaft is evaluated based on the frequency.

Abstract: Disclosed is an evaluation method of a golf club, where a rear end portion of a club shaft is vibrated in a state where a tip portion of the club shaft is fastened to measure a frequency per unit time, and a golf club using the club shaft is evaluated based on the frequency.