Moment of Inertia

Moment of inertia determines how hard it is to rotate an object. A club with weight concentrated in the head has higher MOI, resisting rotation — which means off-center hits twist the face less and fly straighter. Game-improvement clubs use perimeter weighting to maximize this forgiveness.

Tour players choose lower-MOI clubs that rotate more easily, giving them control over shot shape — fades, draws, and intentional curves. The trade-off is clear: forgiveness versus workability. A higher-MOI club goes straighter but cannot be shaped as precisely. A lower-MOI blade responds to every subtle hand movement, rewarding skill and punishing mistakes.