Curb & Training
A basic Western curb bit has a gently ported mouthpiece and shanks to which the reins attach. As the rider takes a feel of the reins, more leverage is exerted on the horse's mouth and also on the poll (where the bridle goes over the head, behind the ears). By increasing the amount of port on the mouthpiece, pressure is applied to the roof of the mouth also. Since Western horses are ridden on a loose rein, the longer shank allows the rider to utilize the leverage by giving extremely light rein aids and attaining the same result as a rider using a snaffle on a firmer contact. In the English curb bit the port can also vary in severity. In general the shanks on English bits are shorter than on Western bits - four to five inches on an English bit as opposed to up to eight or nine inches on a Western one. The English curb bit is often used in a double bridle. In the double bridle, two bits are actually used. One is the curb, called the Weymouth and one is the snaffle, called the Bridoon. Both of these bits are used together to refine the aids in the higher levels of dressage competition.