What is the function of a curb strap on a curb bit?

The function of a curb strap on a curb bit is to provide additional leverage. When the reins are pulled, the curb strap allows the rider to exert a greater amount of pressure on the horse's poll and jaw by creating a leverage effect. This setup enables more subtle communication through the bit, allowing the rider to signal their intentions effectively while having control over the horse's head position.

The curb bit itself operates using leverage, and the curb strap works in conjunction with it to enhance this leverage effect when the reins are engaged. This mechanical advantage is critical for riders who need to guide their horses in various activities, particularly in disciplines that require finer control.

Curb straps do not primarily function to create jaw pressure or enhance the horse's comfort; in fact, excessive leverage can lead to discomfort if not used judiciously. While they can help prevent over-tightening of the bit to some extent, their primary role is to facilitate additional leverage during communication between the rider and horse.