The curb bit was designed for one-handed riding.

Curb bits

Understand the workings of a western curb bit.

The bridle horse working in a curb bit is the epitome of western riding. He’s light in the mouth and moves on a loose rein while responding to the slightest cue from the rider. The bit itself works off leverage, transmitting a light touch of the reins to the horse’s delicate mouth.

The western curb bit is designed for one-handed riding, which traditionally left a cowboy with one hand free for roping. Horses first educated in a hackamore or snaffle bit graduate to the curb bit after extensive training. Today, curbs are used for showing, ranch work and trail and pleasure riding.

Last month we talked about snaffle bits, which are non-leverage bits used for training, pleasure riding and English disciplines. This month we take a look at curb bits and how they work.

The parts of a curb bit

A curb bit is made up of a mouthpiece, shanks (cheek pieces) and a curb strap and works off leverage. When the rider picks up the reins, the bit engages and the shanks pull back toward the rider. At the same time, the curb strap tightens as the mouthpiece rocks forward, in theory placing pressure on the tongue, palate and bars of the horse’s mouth.

Mouthpiece/port: The mouthpiece of the curb bit is the part that rests inside the horse’s mouth and on his bars and tongue. Mouthpieces come in various forms, ranging from high-ported cathedrals and spades to small ports or the broken Tom Thumb-type bits. The broken-type mouthpieces combine the nutcracker effect of the mouthpiece with the leverage of the shank, making some horsemen argue that the broken mouthpiece is more severe than its solid counterparts.

A solid curb bit usually has a port, which is a raised part in the center of the mouthpiece. In theory, a high port can come in contact with the roof of the horse’s mouth. The port also plays a vital role in giving clearance to the sensitive tissue of the tongue, meaning a bit with a shallow port can put unrelenting and painful pressure on the tongue. The maximum height of a port for ApHC competition is 3 1/2 inches. Check the ApHC Official Handbook for additional regulations regarding legal curb shanks and mouthpieces.

Shanks: The shanks put the “curb” in curb bit and are the visible pieces of curved metal you see that make up the cheek pieces of these bits. The shanks are attached, either fixed or loosely, to the bit’s mouthpiece and the rider’s reins.

The shanks create the bit’s signal, which is the delay between engaging the hand and engaging the bit. A bit with a straight shank has a quicker signal or relay than, say, a grazing bit, which has a swept-back shank.

Shank length is also directly proportional to the severity of the curb bit. The longer the shank, the more leverage the bit has and the more severe the bit is in the horse’s mouth. The maximum length for a bit used in ApHC competition is 8 1/2 inches.

Curb strap: The curb strap, also called the chin strap, fixes to the bit and lies under the horse’s chin. The curb strap is necessary in the workings of the curb bit, and no horse should ever wear a curb bit without a curb strap. This small piece of leather, nylon or chain holds the bit in place, keeps the bit from over-rotating in the mouth, and works off leverage to place pressure under the horse’s chin. In ApHC competition, the curb strap must be 1/2 inch wide and lie flat against the horse’s chin.

BY MICHELLE ANDERSON