A method of making a ball bat may include forming a bat frame with a handle and an inner barrel structure, providing spacer elements extending radially outwardly from the inner barrel structure, and forming a barrel shell having a main barrel and a tapered section. An inner diameter in the tapered section may be equal to an outer diameter of a first one of the spacer elements. The method may include mechanically locking the barrel shell to the bat frame by passing the handle through the barrel shell and moving the barrel shell toward the inner barrel structure until the barrel shell contacts the first one of the spacer elements. A gap is maintained between an outer diameter of the inner barrel structure and the barrel shell. The barrel shell may deflect during a hit to create a trampoline effect, while the inner barrel structure limits the deflection.

A bat, which has a hollow barrel and an internal assembly configured to resist deformation of the hollow barrel, is disclosed. The internal assembly includes a rod disposed longitudinally in the hollow barrel, a ring attached to the rod, a deformable sleeve disposed around the ring and extending longitudinally in the hollow barrel. The sleeve can include an outer diameter smaller than an inner diameter of the hollow barrel. The bat can include an end cap attached to an end of the hollow barrel and having a recess configured to receive an end of the rod. The rod can be configured to maintain the deformable sleeve in a predetermined suspended position within the hollow barrel such that, when the bat is at rest, the sleeve is disposed a predetermined gap distance from an inner surface of the hollow barrel.

A method of customizing a golf club, wherein the method includes generating operating data representative of a user operating a mechanical device. The operating data is generated by a first sensor sized and configured to be removably positioned in a mounting port formed on the mechanical device during operation of the mechanical device. The sensor is interchangeably positionable in the mounting port with at least one mass insert, the at least one mass insert being adapted to be interchangeably positioned in the mounting to provide at least two different mass configurations. The method further includes determining a recommended configuration of the at least one mass insert specific to the user based on the operating data generated by the sensor, and transmitting information representative of the recommended mass insert.

A method of customizing a golf club, wherein the method includes generating operating data representative of a user operating a mechanical device. The operating data is generated by a first sensor sized and configured to be removably positioned in a mounting port formed on the mechanical device during operation of the mechanical device. The sensor is interchangeably positionable in the mounting port with at least one mass insert, the at least one mass insert being adapted to be interchangeably positioned in the mounting to provide at least two different mass configurations. The method further includes determining a recommended configuration of the at least one mass insert specific to the user based on the operating data generated by the sensor, and transmitting information representative of the recommended mass insert.

Golf club fitting systems can include a golf club head along with multiple alternative adjustment sleeves that each mate with the club head to modify loft and lie angles. Each adjustment sleeve can include a first portion having a respective longitudinal axis and configured to mate and coaxially align with a hosel of the golf club head, and a second portion having a respective longitudinal axis angularly offset from the longitudinal axis of the first portion and configured to mate and coaxially align with a golf club shaft. Each different adjustment sleeve can be configured to alter a position of the golf club head relative to a golf club shaft by a different adjustment value relative to each other. Fitting systems can also include a shaft sleeve that can join any of various different shafts with any of the adjustment sleeves. Fitting systems can also include additional club heads.

Golf club fitting systems can include a golf club head along with multiple alternative adjustment sleeves that each mate with the club head to modify loft and lie angles. Each adjustment sleeve can include a first portion having a respective longitudinal axis and configured to mate and coaxially align with a hosel of the golf club head, and a second portion having a respective longitudinal axis angularly offset from the longitudinal axis of the first portion and configured to mate and coaxially align with a golf club shaft. Each different adjustment sleeve can be configured to alter a position of the golf club head relative to a golf club shaft by a different adjustment value relative to each other. Fitting systems can also include a shaft sleeve that can join any of various different shafts with any of the adjustment sleeves. Fitting systems can also include additional club heads.

Embodiments of golf clubs with adjustable loft, lie, head mass and methods of manufacturing golf clubs with adjustable loft, lie, and head mass are generally described herein. Other embodiments can be described and claimed.

A golf club head includes a club body having a crown opposite a sole, a toe end opposite a heel end, a back end, and a hosel. A first magnet is coupled to the club body. A second magnet selectively engages the first magnet, such that in a first configuration the first and second magnets attract, and in a second configuration the first and second magnets do not attract, wherein the second magnet is configured to rotate relative to the first magnet between the first configuration and the second configuration.

A golf club head includes a club body having a crown opposite a sole, a toe end opposite a heel end, a back end, and a hosel. A first magnet is coupled to the club body. A second magnet selectively engages the first magnet, such that in a first configuration the first and second magnets attract, and in a second configuration the first and second magnets do not attract, wherein the second magnet is configured to rotate relative to the first magnet between the first configuration and the second configuration.

A marking system for a baseball bat includes a bat including a barrel extending along a central longitudinal axis, the barrel defining a minimal vibration region. The marking system also includes a sheet having a first edge, a second edge positioned opposite the first edge, a third edge positioned between the first and the second edges, and a fourth edge positioned opposite the third edge, the first edge having a first curvature and the second edge having a second curvature, the sheet adapted to at least partially encircle a portion of the barrel of the bat. Additionally, a first positioning feature is disposed on the sheet, and a first alignment feature is disposed proximate the first edge of the sheet. Furthermore, the first positioning feature may be configured to be positioned adjacent to at least a portion of the minimal vibration region.